Opel Insignia: Diagnostic Information and Procedures

DTC P0010, P0013, or P2088-P2091

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0010

Intake Camshaft Position Actuator Solenoid Valve Control Circuit

DTC P0013

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit

DTC P2088

Intake Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage

DTC P2089

Intake Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage

DTC P2090

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage

DTC P2091

Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

For an overview of the component/system, refer to: Camshaft Actuator System Description

The solenoid valve controls the flow of engine oil to the hydraulic actuator that adjusts the angle of the camshaft relative to the position of the crankshaft.

Conditions for Running the DTC

P0010, P0013, P2088, P2089, P2090, P2091

• Camshaft Position Actuator Solenoid Valve=On
• Ignition Switch Position=Run/Crank
• Ignition Voltage=Greater than 11 V

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

P0010, P0013, P2088, P2089, P2090, P2091

Control Circuit=Commanded state does not match the actual state - For greater than 5 s

Actions Taken When the DTC Sets

{WithTurbocharger}DTCs listed in the DTC Descriptor Category=Type A DTC

{WithoutTurbocharger}DTCs listed in the DTC Descriptor Category=Type B DTC - Exceptions listed below

Conditions for Clearing the DTC

{WithTurbocharger}DTCs listed in the DTC Descriptor Category=Type A DTC

{WithoutTurbocharger}DTCs listed in the DTC Descriptor Category=Type B DTC - Exceptions listed below

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

NOTE:

• The engine oil level and the oil pressure are critical to the correct operation of the system. Verify the engine has the correct oil level and the correct oil pressure before continuing with this diagnostic.
• The engine oil condition has a major impact on the camshaft actuator system. Debris in the oil can interfere with the camshaft position actuator solenoid valve and the mechanical camshaft actuator operation. Inspect for dirty or degraded engine oil.
• If a crankshaft or camshaft position sensor DTC is set, the scan tool camshaft position actuator output control will be disabled.

1. Ignition - On / Vehicle - In Service Mode

2. Verify DTC P0335, P0336, P0340, P0341, P0365, P0366 is not set.

• If any of the DTCs are set
• Go to next step: If none of the DTCs are set

3. Verify the following conditions do not exist:

• Engine Oil - Contaminated/Dirty/Fill Level=Low
• Engine Oil Pressure - Low - Refer to: Oil Pressure Diagnosis and Testing
• If a condition exists

Repair as necessary

• Go to next step: If no condition exists

4. Engine - Idling

5. Perform the appropriate scan tool control function:

• Exhaust Camshaft Position Actuator - From 0 to 20º and back to 0º.
• Intake Camshaft Position Actuator - From 0 to 20º and back to 0º.
• Verify the scan tool parameter:
• Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status= OK or Not Run
• Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Open Test Status= OK or Not Run
• Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage Test Status =OK or Not Run
• Intake Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status= OK or Not Run
• Intake Camshaft Position Actuator Solenoid Valve Control Circuit Open Test Status= OK or Not Run
• Intake Camshaft Position Actuator Solenoid Valve Control Circuit High Voltage Test Status= OK or Not Run
• If not the specified state
• Go to next step: If the specified state

6. Perform the scan tool control function:

• Exhaust Camshaft Position Actuator - From 0 to 20º and back to 0º.
• Intake Camshaft Position Actuator - From 0 to 20º and back to 0º.
• Verify the scan tool parameter:
• Exhaust Camshaft Position Variance=Less than 2º - During each of the commanded states
• Intake Camshaft Position Variance=Less than 2º - During each of the commanded states
• If 2º or greater
• Go to next step: If less than 2º

7. Verify the scan tool parameter:

• Intake Camshaft Position Variance=Less than 2º
• Exhaust Camshaft Position Variance=Less than 2º
• Perform the action while monitoring the parameter:
• Wiggle the harness and connector: Q6 Camshaft Position Actuator Solenoid Valve
• Wiggle the harness and connector: K20 Engine Control Module
• If 2º or greater

Repair as necessary - Wiring / Terminal (s) / Electrical Connector (s)

• Go to next step: If less than 2º

8. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets
• Go to next step: If the DTC is not set

9. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the appropriate electrical connector: Q6 Camshaft Position Actuator Solenoid Valve.

3. Test for less than 10 ohms between the test points: Low Reference circuit terminal 2/B & Ground.

• If 10 ohms or greater

1. Disconnect the appropriate electrical connector: K20 Engine Control Module
2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 2/B@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If less than 10 ohms

4. Ignition - On / Vehicle - In Service Mode.

5. Perform the scan tool control function:

• Exhaust Camshaft Position Actuator Solenoid Valve - Off
• Intake Camshaft Position Actuator Solenoid Valve - Off

Verify a test lamp does not turn On between the test points: Control circuit terminal 1/A & Ground

• If the test lamp turns On

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Control circuit terminal 1/A@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If the test lamp does not turn On

6. Remove - Test Lamp

7. Perform the scan tool control function:

• Exhaust Camshaft Position Actuator Solenoid Valve - On
• Intake Camshaft Position Actuator Solenoid Valve - On
• Verify the scan tool parameter:
• Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status= OK or Not Run
• Intake Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status= OK or Not Run
• If not the specified state

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Control circuit terminal 1/A@Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • If infinite resistance - Replace the component: K20 Engine Control Module

• Go to next step: If the specified state

8. Connect a 3 A fused jumper wire between the test points: Control circuit terminal 1/A & Ground

9. Perform the scan tool control function:

• Exhaust Camshaft Position Actuator Solenoid Valve - On
• Intake Camshaft Position Actuator Solenoid Valve - On
• Verify the scan tool parameter:
• Exhaust Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status=Malfunction
• Intake Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status=Malfunction
• If not the specified state

1. Ignition/Vehicle - Off & Remove - Jumper wire (s)
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for less than 2 ohms between the test points: Control circuit terminal 1/A@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If the specified state

10. Verify DTC P0011, P0014 is not set.

• If the DTC is set

1. Ignition/Vehicle - Off
2. Remove the component: Q6 Camshaft Position Actuator Solenoid Valve
3. Verify a condition does not exist with the component: Q6 Camshaft Position Actuator Solenoid Valve
   • Engine Oil - Leaking@Harness Connector
   • Screen - Misaligned/Missing/Restricted/Torn
   • Valve - Scored/Visible Damage
   • If a condition exists - Replace the component: Q6 Camshaft Position Actuator Solenoid Valve
   • Go to next step: If no condition exists

NOTE: It may be necessary to use jumper wires if the connector indexing is different between the connectors.

4. Swap the two components:
   • Q6E Camshaft Position Actuator Solenoid Valve - Exhaust
   • Q6F Camshaft Position Actuator Solenoid Valve - Intake
5. Engine - Running

NOTE:

• This step is testing the mechanical camshaft position actuator for the camshaft that set the DTC.
• Perform this test at the original location that set the DTC.

6. Perform the scan tool control function:
   • Exhaust Camshaft Position Actuator - From 0 to 20º and back to 0º.
   • Intake Camshaft Position Actuator - From 0 to 20º and back to 0º.
   • Verify the scan tool parameter:
   • Exhaust Camshaft Position Variance=Less than 2º - During each of the commanded states
   • Intake Camshaft Position Variance=Less than 2º - During each of the commanded states
   • If 2º or greater - Replace the component: Camshaft Position Actuator
   • If less than 2º - Replace the component: Q6 Camshaft Position Actuator Solenoid
   • Valve - The original component that set the DTC

• Go to next step: If the DTC is not set

11. Test or replace the component: Q6 Camshaft Position Actuator Solenoid Valve

Component Testing

Static Test

1. Ignition/Vehicle - Off

2. Disconnect the appropriate electrical connector: Q6 Camshaft Position Actuator Solenoid Valve

3. Test for 5 to 12 ohms between the test points: Control terminal 1/A & Low Reference terminal 2/B

• If not between 5 and 12 ohms

Replace the component: Q6 Camshaft Position Actuator Solenoid Valve

• Go to next step: If between 5 and 12 ohms

4. Test for infinite resistance between the test points: Each terminal of the component & The component's housing

• If less than infinite resistance

Replace the component: Q6 Camshaft Position Actuator Solenoid Valve

• Go to next step: If infinite resistance

5. All OK.

Dynamic Test

1. Ignition/Vehicle - Off

2. Disconnect the appropriate electrical connector: Q6 Camshaft Position Actuator Solenoid Valve

3. Connect a jumper wire between the test points: Low Reference terminal 2/B & Ground

4. Momentarily connect a 7.5 A fused jumper wire between the test points: Control terminal 1/A & B+

Verify the component turns On and Off when connecting and disconnecting the jumper wire: Q6 Camshaft Position Actuator Solenoid Valve

• If the component does not turn On and Off

Replace the component: Q6 Camshaft Position Actuator Solenoid Valve

• Go to next step: If the component turns On and Off

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Camshaft Position Actuator and Camshaft Replacement - Exhaust
• Camshaft Position Actuator and Camshaft Replacement - Intake
• Camshaft Position Actuator Exhaust Solenoid Valve Replacement
• Camshaft Position Actuator Intake Solenoid Valve Replacement
• For control module replacement, programming, and setup refer to: Control Module References

DTC P0011 or P0014

Diagnostic Instructions

• Perform the Diagnostic System Check Instructions prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0011

Intake Camshaft Position System Performance

DTC P0014

Exhaust Camshaft Position System Performance

Diagnostic Fault Information

Circuit/System Description

The camshaft position actuator system enables the engine control module (ECM) to change the timing of the camshafts while the engine is operating. The camshaft position actuator solenoid valves are each supplied a dedicated pulse width modulated (PWM) control circuit and low reference circuit from the ECM. The ECM operates each camshaft position actuator solenoid valve by controlling the amount of solenoid valve signal duty cycle to control the oil flow that applies the pressure to advance or retard the camshafts.

Conditions for Running the DTC

• DTC P0010, P0013, P0016, P0017, P0335, P0336, P0340, P0341, P0365, or P0366 is not set.
• The ignition voltage is greater than 11 V.
• The engine is operating.
• The desire camshaft position is not changing greater than 3.0 degrees for at least 3 s.
• Both of the desired and actual camshaft position actuator values cannot be greater than 29 degrees or less than 6 degrees.

The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

The ECM detects the difference between the desired camshaft position angle and the actual camshaft position angle is greater than 6 degrees for greater 13.5 s.

Action Taken When the DTC Sets

• DTCs listed in the DTC Descriptor Category=Type B DTC - Exceptions listed below

If equipped with a turbocharger=Type A DTC

• The Auto Stop and Auto Start function of the hybrid system is disabled.

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type B DTC - Exceptions listed below

If equipped with a turbocharger=Type A DTC

Diagnostic Aids

• A low oil level or condition may set this DTC.
• Inspect the engine for any recent engine mechanical repairs. An incorrectly installed camshaft, camshaft actuator, or timing chain can cause this DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Description and Operation

Camshaft Actuator System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Circuit/System Verification

NOTE:

• The engine oil level and the oil pressure are critical to the correct operation of the camshaft position actuator system. Verify that the engine has the correct oil level and the correct oil pressure before continuing with this diagnostic.
• The engine oil condition has a major impact on the camshaft actuator system. Debris in the oil can interfere with the camshaft position actuator solenoid and the mechanical camshaft actuator operation. Inspect for dirty or degraded crankcase oil. The engine may require an oil change. Inquire with the customer when the last oil change was performed. You may also monitor the scan tool Engine Oil Life Remaining parameter. Advise the customer an oil change may be required.

1. Verify the engine has the proper oil condition, level, and pressure. Refer to Oil Pressure Diagnosis and Testing.

• If the oil condition, level, and oil pressure are not correct

Repair as necessary.

• Go to next step: If the oil condition, level, and oil pressure are correct

2. Verify DTC P0010, P0011, P0013, P0014, P0016, P0017, P0335, P0336, P0340, P0341, P0365, P0366, P2088, P2089, P2090 or P2091 is not set.

• If any DTCs other than P0011 or P0014 are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• If only DTC P0011 or P0014 is set

1. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
2. Verify the DTC does not set.
   • If the DTC sets, refer to Circuit/System Testing.
   • If the DTC does not set, all OK.

• Go to next step: If none of the DTCs are set

3. All OK.

Circuit/System Testing

NOTE: You must complete the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the appropriate Q6 Camshaft Position Actuator Solenoid Valve, ignition ON.

2. Verify a test lamp illuminates between the control circuit terminal 1 or A and ground when commanding the appropriate Camshaft Position Actuator Solenoid Valve On with a scan tool.

• If the test lamp does not illuminate

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.

• If 2 Ω or greater, repair the open/high resistance or short to ground in the circuit.
• If less than 2 Ω, replace the K20 Engine Control Module.
• Go to next step: If the test lamp illuminates

3. Ignition OFF.

4. Remove the appropriate Q6 Camshaft Position Actuator Solenoid Valve. Inspect the Camshaft Position Actuator Solenoid Valve and mounting area for the following conditions:

• For a torn, restricted, incorrect positioned, or missing screens at the Q6 Camshaft Position Actuator Solenoid Valve
• For engine oil leaks between the oil sealing lands of the Q6 Camshaft Position Actuator Solenoid Valve
• For oil seepage at the Q6 Camshaft Position Actuator Solenoid Valve connector

• If a condition is found

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If a condition is not found

NOTE: This step is testing the mechanical operation of the camshaft position actuator solenoid valve that set the DTC.

5. Exchange the suspected Q6 Camshaft Position Actuator Solenoid Valve with a Q6 Camshaft Position Actuator Solenoid Valve that is operating correctly.

6. Engine Running.

7. Command the appropriate camshaft position actuator from 0 degrees to 20 degrees and back to zero while observing the appropriate scan tool Intake/Exhaust Camshaft Position Variance parameters. The Intake/Exhaust Camshaft Position Variance should be less than 2 degrees in each of the commanded states.

• If the Camshaft Position Variance parameter is greater than 2 degrees

Replace or repair the mechanical camshaft position actuator.

• Go to next step: If the Camshaft Position Variance parameter is less than 2 degrees

8. Test or replace the Q6 Camshaft Position Actuator Solenoid Valve.

Component Testing

1. Ignition OFF, disconnect the harness connector at the appropriate Q6 Camshaft Position Actuator Solenoid Valve.

2. Test for 7 - 12 Ω between the control terminal 1 or A and the low reference circuit terminal 2 or B.

• If not between 7 - 12 Ω

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If between 7 - 12 Ω

3. Test for infinite resistance between each terminal and the Q6 Camshaft Position Actuator Solenoid Valve housing.

• If less than infinite resistance

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If infinite resistance

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Camshaft Position Actuator Intake Solenoid Valve Replacement
• Camshaft Position Actuator Exhaust Solenoid Valve Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0016 or P0017

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0016

Crankshaft Position - Intake Camshaft Position Not Plausible

DTC P0017

Crankshaft Position - Exhaust Camshaft Position Not Plausible

Circuit/System Description

The engine control module (ECM) uses the crankshaft position sensor, intake camshaft position sensor, and exhaust camshaft position sensor information to monitor the correlation between the crankshaft, intake camshaft, and exhaust camshaft position.

Conditions for Running the DTC

• DTC P0335, P0336, P0340, P0341, P0365, P0366, P0641, and P0651 are not set.
• The engine is cranking or running.
• The crankshaft and camshaft position signals are synchronized.
• The camshaft position actuator solenoid valves are in the parked position.

The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

The ECM detects a camshaft that is greater than 8 degrees advanced or 9 degrees retarded in relationship to the crankshaft.

Action Taken When the DTC Sets

DTCs P0016 and P0017 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0016 and P0017 are Type B DTCs.

Diagnostic Aids

• Inspect the engine for any recent engine mechanical repairs. An incorrectly installed timing chain can cause this DTC to set.
• A camshaft position actuator solenoid valve that is in the full advance or retard position can cause this DTC to set.

Reference Information

Description and Operation

Camshaft Actuator System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0010, P0013, P0335, P0336, P0340, P0341, P0365, or P0366 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

3. Engine Running at normal operating temperature.

4. Verify DTC P0016 or P0017 is not set.

• If the DTC is set

Inspect for the following and repair as necessary:

• A Q6 Camshaft Position Actuator Solenoid Valve that is stuck in the full advance or retard position.
• The correct installation of the Q6 Camshaft Position Actuator Solenoid Valves.
• The correct installation of the B23 Camshaft Position Sensors.
• The correct installation of the B26 Crankshaft Position Sensor.
• A timing chain tensioner condition.
• An incorrectly installed timing chain.
• Excessive play in the timing chain.
• A timing chain that jumped teeth.
• A crankshaft reluctor wheel that has moved in relationship to top dead center (TDC) on the crankshaft.
• Go to next step: If the DTC is not set

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets

A mechanical condition listed above still exists.

• Go to next step: If the DTC does not set

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Camshaft Position Actuator Exhaust Solenoid Valve Replacement
• Camshaft Position Actuator Intake Solenoid Valve Replacement
• Camshaft Position Sensor Replacement - Exhaust
• Camshaft Position Sensor Replacement - Intake
• Crankshaft Position Sensor Replacement
• Timing Chain Tensioner Replacement

DTC P0030-P0032, P0036-P0038, P0054, P0135, P0141, P103B, or P103C

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0030

HO2S Heater Control Circuit Sensor 1

DTC P0031

HO2S Heater Control Circuit Low Voltage Sensor 1

DTC P0032

HO2S Heater Control Circuit High Voltage Sensor 1

DTC P0036

HO2S Heater Control Circuit Sensor 2

DTC P0037

HO2S Heater Control Circuit Low Voltage Sensor 2

DTC P0038

HO2S Heater Control Circuit High Voltage Sensor 2

DTC P0054

HO2S Heater Resistance Sensor 2

DTC P0135

HO2S Heater Performance Sensor 1

DTC P0141

HO2S Heater Performance Sensor 2

DTC P103B

HO2S Heater Supply Voltage Sensing Circuit Performance

DTC P103C

HO2S Heater Supply Voltage Sensing Circuit Low Voltage

Diagnostic Fault Information

Circuit/System Description

Conditions for Running the DTC

P0030, P0031, P0032, P0036, P0037, P0038

• Engine Speed=Greater than 400 RPM
• Ignition Voltage=11 to 32 V

Frequency the DTC runs=Continuously - After the running conditions are met - For greater than 5 s

P0053

• DTCs related to the following system/component = Not Set
  • B34 Engine Coolant Temperature Sensor
  • B111B Turbocharger Boost/Intake Air Temperature Sensor
• ECT Sensor & IAT Sensor=Within 8ºC (14ºF) of each other
• ECT Sensor=30 to 255ºC (86 to 491ºF)
• Engine=Running
• Ignition Voltage=Less than 32 V

Frequency the DTC runs=Once - Per cold start-up - After the running conditions are met

P0135, P0141

• DTC P0116, P0117, P0118, P0119, P0128, P111E = Not set
• HO2S Heater=Device controls are not active.
• HO2S 1, 2 Heater Command=Greater than 0% Duty Cycle
• Ignition Voltage=10 to 32 V

Frequency the DTC runs=2 times - Per drive cycle - After the running conditions are met - For greater than 120 s

P103B, P103C

• Engine= Cranking or Running
• Ignition Voltage=10 to 32 V

Frequency the DTC runs=Continuously - After the running conditions are met - For greater than 3 s

Conditions for Setting the DTC

P0030, P0031, P0032, P0036, P0037, P0038

Control Circuit=Commanded state does not match the actual state - For greater than 5 s

P0053, P0054

HO2S Heater Resistance=Resistance Out Of Range - During engine startup

P0135, P0141

HO2S 1, 2 Heater 0.3 to 2.5 A - For greater than 10 s

P103B

HO2S Heater Supply Voltage & Ignition Voltage=Not within 2 V of each other - For greater than 3 s

P103C

HO2S Heater Supply Voltage=Less than 6 V - For greater than 3 s

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type B DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type B DTC

Diagnostic Aids

High resistance in the circuits of the component may set DTC P103B, P103C without setting the DTC for the component: B52 Heated Oxygen Sensor

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Engine - Idling - At normal operating temperature

NOTE: This step only applies to the following component DTCs: HO2S Heater.

2. Verify DTC P103B, P103C is not set and no other DTCs are set.

• If DTC P103B, P103C is set and other DTCs are set
• If DTC P103B, P103C is not set and other DTCs are set
• If DTC P103B, P103C is set and no other DTCs are set
• Go to next step: If no DTC is set

3. Verify the scan tool parameter:

• HO2S 1, 2 Heater Control Circuit High Voltage Test Status= OK or Not Run
• HO2S 1, 2 Heater Control Circuit Low Voltage Test Status= OK or Not Run
• HO2S 1, 2 Heater Control Circuit Open Test Status= OK or Not Run
• If not the specified state
• Go to next step: If the specified state

4. Verify the scan tool parameter:

HO2S 1, 2 Heater=0.3 to 2.4 A

• If not between 0.3 and 2.4 A
• Go to next step: If between 0.3 and 2.4 A

5. Verify the scan tool parameter: HO2S 1, 2 Heater=The value should not spike or drop out.

Perform the action while monitoring the parameter:

• Wiggle the harness and connector: B52 Heated Oxygen Sensor
• Wiggle the harness and connector: K20 Engine Control Module
• If the value spikes or drops out

Repair as necessary - Wiring / Terminal (s) / Electrical Connector (s)

• Go to next step: If the value does not spike or drop out

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to step 2

• Go to next step: If the DTC is not set

7. All OK.

Circuit/System Testing

Test 1

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the appropriate electrical connector: B52 Heated Oxygen Sensor.

3. Ignition - On / Vehicle - In Service Mode.

4. Verify a test lamp turns On between the test points:

• {B52A Heated Oxygen Sensor 1}Ignition circuit terminal 5 & Ground
• {B52B Heated Oxygen Sensor 2}Ignition circuit terminal 2 & Ground
• If the test lamp does not turn On and the circuit fuse is OK

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Test for less than 2 ohms between the test points:
   • {B52A Heated Oxygen Sensor 1}Ignition circuit terminal 5 & Output terminal@Fuse
   • {B52B Heated Oxygen Sensor 2}Ignition circuit terminal 2 & Output terminal@Fuse
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Verify the fuse is OK and there is voltage at the fuse.

• If the test lamp does not turn On and the circuit fuse is open

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Connect the electrical connector: B52 Heated Oxygen Sensor
3. Ignition - On / Vehicle - In Service Mode
4. Replace the component: Fuse
5. Verify the fuse does not open.
   • If the fuse opens and there are components connected to the circuit - Disconnect a component and repeat step 4.4
   • If the fuse opens with all components disconnected from the circuit - Repair the short to ground on the circuit.
   • If the fuse does not open after disconnecting a component from the circuit - Replace the component disconnected last.
   • Go to next step: If the fuse does not open with all components connected.

NOTE: It may be necessary to use a scan tool control function to operate a component.

6. Operate the component: Each component on the circuit - One at a time

Verify the fuse does not open when any of the components are activated.

• If the fuse opens - Replace the component that caused the fuse to open when activated.
• Go to next step: If the fuse does not open.

7. All OK.

• Go to next step: If the test lamp turns On

5. Verify a test lamp does not turn On between the test points:

• {B52A Heated Oxygen Sensor 1}Ignition circuit terminal 5 & Control circuit terminal 6
• {B52B Heated Oxygen Sensor 2}Ignition circuit terminal 2 & Control circuit terminal 1
• If the test lamp turns On

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points:
   • {B52A Heated Oxygen Sensor 1}Control circuit terminal 6@Component harness & Ground
   • {B52B Heated Oxygen Sensor 2}Control circuit terminal 1@Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • If infinite resistance - Replace the component: K20 Engine Control Module

• Go to next step: If the test lamp does not turn On

6. Remove - Test Lamp.

7. Engine - Running.

8. Verify the scan tool parameter: HO2S 1, 2 Heater Control Circuit Open Test Status=Malfunction.

• If not the specified state

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points:
   • {B52A Heated Oxygen Sensor 1}Control circuit terminal 6@Component harness & Ground
   • {B52B Heated Oxygen Sensor 2}Control circuit terminal 1@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If the specified value

NOTE:

• As little as 10 ohms of resistance in a circuit may cause a DTC to set.
• Performing this test may set additional DTCs.

9. Connect a 3 A fused jumper wire between the test points:

• {B52A Heated Oxygen Sensor 1}Ignition circuit terminal 5 & Control circuit terminal 6
• {B52B Heated Oxygen Sensor 2}Ignition circuit terminal 2 & Control circuit terminal 1

10. Engine - Running

11. Verify the scan tool parameter: HO2S 1, 2 Heater Control Circuit High Voltage Test Status =Malfunction

• If not the specified state

1. Ignition/Vehicle - Off & Remove - Jumper wire (s)
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for less than 2 ohms between the test points:
   • {B52A Heated Oxygen Sensor 1}Control circuit terminal 6@Component harness & The other end of the circuit@Control module harness
   • {B52B Heated Oxygen Sensor 2}Control circuit terminal 1@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If the specified state

12. Test or replace the component: B52 Heated Oxygen Sensor

Test 2

1. Ignition/Vehicle - Off.

2. Disconnect the appropriate electrical connector: K20 Engine Control Module.

3. Test for less than 2 ohms between the test points: Output terminal@Fuse & The other end of the circuit@Control module harness.

• If 2 ohms or greater

Repair the open/high resistance in the circuit:

• Go to next step: If less than 2 ohms

4. Replace the component: K20 Engine Control Module

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Heated Oxygen Sensor Replacement - Sensor 1
• Heated Oxygen Sensor Replacement - Sensor 2
• For control module replacement, programming, and setup refer to: Control Module References

DTC P0033-P0035

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0033

Turbocharger Bypass Solenoid Valve Control Circuit

DTC P0034

Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage

DTC P0035

Turbocharger Bypass Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The dual-scroll turbocharger incorporates a wastegate that is controlled by the engine control module (ECM) by means of a pulse width modulation (PWM) solenoid, to regulate the pressure ratio of the compressor. An ECM controlled compressor bypass valve is integrated into the unit to prevent compressor surging and damage from vibrations by opening during abrupt closed throttle conditions.

The bypass valve is open during closed throttle deceleration conditions to allow air to recirculate in the turbocharger and maintain compressor speed.

As engine load and RPM increase, the turbocharger bypass valve is commanded closed by the ECM. As soon as the throttle closes, the valve is commanded open to allow the turbocharger air to recirculate to prevent compressor surging.

Conditions for Running the DTCs

• Ignition is On or the engine is running.
• Battery voltage is between 11 - 32 V.
• The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTCs

The ECM detects an open, a short to ground, or a short to voltage on the turbocharger bypass solenoid valve control circuit for greater than 10 s.

Action Taken When the DTCs Set

DTCs P0033, P0034, and P0035 are Type B DTCs.

Conditions for Clearing the MIL/DTCs

DTCs P0033, P0034, and P0035 are Type B DTCs

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

1. Ignition On

2. Verify a click is heard or felt from the Q40 Turbocharger Bypass Solenoid Valve when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• If a click is not heard or felt
• Go to next step: If a click is heard or felt

3. Verify the circuit status parameters listed below do not display Malfunction when commanding the Turbocharger Bypass Solenoid Valve between Inactive and Active with a scan tool:

• Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status
• Turbocharger Bypass Solenoid Valve Control Circuit Open Test Status
• Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage Test Status
• If Malfunction is displayed
• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify a DTC does not set.

• If a DTC sets
• Go to next step: If a DTC does not set

6. All OK

Circuit/System Testing

1. Ignition Off, disconnect the harness connector at the Q40 Turbocharger Bypass Solenoid Valve, ignition On.

2. Verify a test lamp illuminates between the ignition circuit terminal 1 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition Off.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition Off, remove the test lamp.

NOTE: An short circuit in any component supplied by the fuse may cause the fuse to open and set a DTC when the component is activated.

2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components supplied by the fuse and replace as necessary.

• Go to next step: If the test lamp illuminates

3. Verify that a test lamp does not illuminate between the control circuit terminal 2 and the ignition circuit terminal 1.

• If the test lamp illuminates

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status parameter is OK when commanding the Turbocharger Bypass Solenoid Valve Active with a scan tool.

• If OK is not displayed

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal 2 and the ignition circuit terminal 1.

7. Verify the scan tool Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status parameter is Malfunction when commanding the Turbocharger Bypass Solenoid Valve Active with a scan tool.

• If Malfunction is not displayed

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If Malfunction is displayed

8. Test or replace the Q40 Turbocharger Bypass Solenoid Valve.

Component Testing

Static Test

1. Ignition Off, disconnect the harness connector at the Q40 Turbocharger Bypass Solenoid Valve.

2. Test for 10 - 14 Ω between the control terminal 2 and the Ignition terminal 1 of the Q40 Turbocharger Bypass Solenoid Valve.

• If not between 10 - 14 Ω

Replace the Q40 Turbocharger Bypass Solenoid Valve.

• Go to next step: If between 10 - 14 Ω

3. All OK

Dynamic Test

1. Install a 10 A fused jumper wire between the ignition terminal 2 of the Q40 Turbocharger Bypass Solenoid Valve and 12 V. Install a jumper wire between the control terminal 1 and ground.

2. Verify the Q40 Turbocharger Bypass Solenoid Valve plunger retracts.

• If the plunger does not retract.

Replace the Q40 Turbocharger Bypass Solenoid Valve.

• Go to next step: If the plunger retracts.

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Turbocharger Bypass Valve Solenoid Replacement
• Control Module References for ECM replacement, programming, and setup

DTC P0068 or P1101

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0068

Throttle Body Air Flow Performance

DTC P1101

Intake Air Flow System Performance

Circuit/System Description

The engine control module (ECM) compares actual air flow based on throttle position (TP) to a calculated airflow based on manifold absolute pressure (MAP) sensor, and mass air flow (MAF).

Conditions for Running the DTC

DTC P0068

• The engine speed is at least 800 RPM.
• The ignition voltage is at least 6.4 V.
• The DTC runs continuously when the above conditions are met.

DTC P1101

• DTC P0101, P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0116, P0117, P0118, P0128, P0335, or P0336 is not set
• The engine speed is between 575 - 6, 600 RPM
• The engine coolant temperature (ECT) is between -7 to +129ºC (+19 to +264ºF).
• The intake air temperature (IAT) is between -20 to +125ºC (-4 to +257ºF).
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTCs

The ECM detects that the actual airflow rate is greater than the calculated airflow.

Action Taken When the DTCs Set

• DTC P0068 is a type A DTC.
• DTC P1101 is a type B DTC.

Conditions for Clearing the DTCs

• DTC P0068 is a type A DTC.
• DTC P1101 is a type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, verify that DTC P0641, P0651, P0697, or P06A3 is not set.

• If any of the DTCs are set
• Go to next step: If none of the DTCs are set

2. If you were sent here from DTC P0068, P0106, P0121, P0236, or P1101; refer to Circuit/System Testing.

3. Ignition ON, verify the scan tool Throttle Body Idle Air Flow Compensation parameter is less than 90 %.

• 90 % or greater
• Go to next step: If less than 90 %

4. Verify the scan tool Throttle Position Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Disagree
• Go to next step: If Agree

5. Determine the current vehicle testing altitude.

6. Verify the scan tool MAP Sensor pressure parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the MAP Sensor parameter is not in range

Refer to DTC P0106 for further diagnosis.

• Go to next step: If the MAP Sensor parameter is within range

7. Verify the engine is equipped with a turbocharger.

• If not equipped with a turbocharger

Refer to Step 10.

• Go to next step: If equipped with a turbocharger

8. Verify the scan tool Boost Pressure Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the Boost Pressure Sensor parameter is not in range

Refer to DTC P0236 for further diagnosis.

• Go to next step: If the Boost Pressure Sensor parameter is within range

9. Verify the scan tool Boost Pressure Sensor parameter decreases after starting the engine.

• If the Boost Pressure Sensor parameter does not decrease

Refer to DTC P0236 for further diagnosis.

Go to next step: If the Boost Pressure Sensor parameter does decrease

10. Engine idling, verify the scan tool MAP Sensor pressure parameter is between 26 - 52 kPa (3.8 - 7.5 PSI) and changes with accelerator pedal input.

• If not between 26 - 52 kPa (3.8 - 7.5 PSI) or does not change

Refer to DTC P0106 for further diagnosis.

• Go to next step: If between 26 - 52 kPa (3.8 - 7.5 PSI) and changes

11. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3, 000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• If the MAF Sensor parameter does not change smoothly and gradually

Refer to DTC P0101 for further diagnosis.

• Go to next step: If the MAF Sensor parameter changes smoothly and gradually

12. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

13. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

14. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Verify the integrity of the entire air induction system by verifying that none of the following conditions exist:

• Any damaged, improperly installed, collapsed, or restricted components
• Improper operation of turbocharger wastegate actuator or bypass valve, where equipped
• Loose clamps, cracks, or other damage
• An air flow restriction
• Restricted air filter
• Splits, kinks, leaks, or improper connections at the vacuum hoses
• Vacuum leaks at the intake manifold, MAP sensor, and throttle body
• Water intrusion
• Any snow or ice buildup, in cold climates
• Contamination of the MAF sensor element
• Missing, restricted, or leaking exhaust components - Refer to Symptoms - Engine Exhaust for further diagnosis.
• If a condition is found

Repair or replace component as appropriate.

• Go to next step: If no condition is found

2. Test the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical for diagnosis.

• If a condition is found

Repair or replace component as appropriate.

• Go to next step: If no condition is found

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for engine control module replacement, programming, and setup

DTC P0089, P00C6, P053F, P228C, or P228D

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0089

Fuel Pressure Regulator Performance

DTC P00C6

Fuel Rail Pressure Low During Engine Cranking

DTC P228C

Fuel Pressure Regulator Control Performance - Low Pressure

DTC P228D

Fuel Pressure Regulator Control Performance - High Pressure

Circuit/System Description

The high fuel pressure necessary for direct injection is supplied by the high pressure fuel pump. The high pressure fuel pump is mounted on the rear of the engine and is driven by a three-lobe cam on the intake camshaft. This high pressure fuel pump also regulates the fuel pressure using an actuator in the form of an internal solenoid-controlled valve. In order to keep the engine running efficiently under all operating conditions, the engine control module (ECM) requests pressure ranging from 2 to 15 MPa (290 to 2, 176 PSI), depending on engine speed and load. Output drivers in the ECM provide the pump control circuit with a 12 V pulse-width modulated (PWM) signal, which regulates fuel pressure by closing and opening the control valve at specific times during pump strokes. This effectively regulates the portion of each pump stroke that is delivered to the fuel rail. When the control solenoid is NOT powered, the pump operates at maximum flow rate. In the event of pump control failure, the high pressure system is protected by a relief valve in the pump that prevents the pressure from exceeding 17.5 MPa (2, 538 PSI).

The fuel rail pressure sensor provides the feedback necessary to the ECM to control the high pressure fuel pump and the fuel injectors. This sensor is diagnosed separately from the fuel pressure control system.

The ECM monitors the fuel rail pressure sensor and the high pressure fuel pump actuator to determine if the commanded and actual pressures are within a predetermined range during engine cranking and at all times while the engine is running. The ECM also monitors the fuel pump actuator to make sure it is operating within expected limits.

Conditions for Running the DTC

P0089, P228C, or P228D

• DTC P0016, P0017, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0128, P0191, P0192, P0193, P0335, P0336, P0340, P0341, P0365, P0366, P0628, or P1682 is not set.
• The ignition voltage is greater than 8 V.
• The engine is running.
• The low side fuel pressure is greater than 250 kPa (36 PSI).
• The barometric (BARO) pressure is greater than 70 kPa.
• The intake air temperature (IAT) is warmer than -20ºC (-4ºF).
• The DTCs run continuously when the above conditions are met for 60 s.

P00C6

• DTC P0016, P0017, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0128, P0191, P0192, P0193, P0335, P0336, P0340, P0341, P0365, P0366, P0628, or P1682 is not set.
• The ignition voltage is greater than 8 V.
• The engine coolant temperature is less than 65ºC (149ºF).
• The low side fuel pressure is greater than 300 kPa (44 PSI).
• The diagnostic runs once for each engine start.

Conditions for Setting the DTC

P0089

The high pressure fuel pump has exceeded it's control limits. This condition exists when the high pressure fuel pump actuator command is 0º or greater than 240º. The condition exists for greater than 10 s.

P00C6

The ECM detects that the fuel rail pressure is not rising greater than 3 MPa (435 PSI) or has fallen below 2 MPa (290 PSI) during engine cranking, depending on initial pressure when cranking begins.

P228C

The actual fuel rail pressure is 3 MPa (435 PSI) less than the desired fuel rail pressure. The condition exists for greater than 10 s.

P228D

The actual fuel rail pressure is 3 MPa (435 PSI) greater than the desired fuel rail pressure. The condition exists for greater than 10 s.

Action Taken When the DTC Sets

• DTCs P0089 and P00C6 are Type B DTCs.
• DTCs P228C and P228D are Type A DTCs.
• A message center or an indicator displays Reduced Engine Power.
• Scan tool control of the high pressure fuel pump is inhibited.

Conditions for Clearing the DTC

• DTCs P0089 and P00C6 are Type B DTCs.
• DTCs P228C and P228D are Type A DTCs.

Diagnostic Aids

• Any problem with the camshaft may set fuel pressure DTCs due to the location and design of the high pressure fuel pump. If camshaft position control DTCs are current or in history, a cam control issue may be the root cause.
• A faulty valve, plunger, or solenoid in the high pressure fuel pump may set a DTC. High pressure fuel pump damage will most likely be undetectable upon visual inspection.
• A restricted fuel feed pipe between the fuel feed pipe fuel pressure sensor and the high pressure fuel pump may set a DTC.
• A leaking or restricted fuel injector may set a DTC.
• A leak in the high pressure fuel system may set a DTC.
• Vapor lock may set DTC P0089

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Attempt to start and idle the engine.

2. Observe the DTC information with a scan tool. DTCs P0089, P00C6, P228C, and P228D should not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

3. Engine idling.

4. Verify the scan tool Fuel Rail Pressure Sensor parameter is approximately 1.9 - 5.0 MPa (276 - 725 PSI).

• If not between 1.9 - 5.0 MPa (276 - 725 PSI)

Refer to Circuit/System Testing.

• Go to next step: If between 1.9 - 5.0 MPa (276 - 725 PSI)

WARNING: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.

5. Road test the vehicle and perform a wide open acceleration from a stop until the transmission shifts into second gear. On manual transmission applications, shift to second gear or stop the test near 2, 500 RPM. Repeat the test at least three times.

6. Verify DTCs P0089, P00C6, P228C, and P228D do not set.

• If any of the DTCs set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs set

7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

8. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

9. All OK.

Circuit/System Testing

NOTE: Circuit/System Verification must be performed first or misdiagnosis may result.

1. Remove the G18 High Pressure Fuel Pump.

2. Verify the lobes on the camshaft do not have unusual wear or are worn.

• If the lobes have unusual wear or are worn

Replace the Camshaft.

• Go to next step: If the lobes are OK

3. Test or replace the G18 High Pressure Fuel Pump.

Component Testing

1. Ignition OFF, disconnect the harness connector at the G18 High Pressure Fuel Pump.

NOTE: The DMM and test leads must be calibrated to 0 Ω in order to prevent misdiagnosis.

2. Test for 0.3 - 0.7 Ω at 20ºC (68ºF) between the high control circuit terminal 1 and the low control circuit terminal 2.

• If not between 0.3 - 0.7 Ω

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If between 0.3 - 0.7 Ω

3. Test for infinite resistance between each terminal and the G18 High Pressure Fuel Pump housing.

• If less than infinite resistance

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If infinite resistance

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Camshaft Position Actuator and Camshaft Replacement - Intake
• Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement
• Fuel Pump Replacement for G18 High Pressure Fuel Pump replacement
• Perform the Fuel Rail Pressure Relief Valve Reset procedure, if supported on the scan tool.

DTC P0090-P0092, P00C8, P00C9, or P00CA

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0090

Fuel Pressure Regulator Control Circuit

DTC P0091

Fuel Pressure Regulator Control Circuit Low Voltage

DTC P0092

Fuel Pressure Regulator Control Circuit High Voltage

DTC P00C8

Fuel Pressure Regulator High Control Circuit

DTC P00C9

Fuel Pressure Regulator High Control Circuit Low Voltage

DTC P00CA

Fuel Pressure Regulator High Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The high fuel pressure necessary for direct injection is supplied by the high pressure fuel pump. The high pressure fuel pump is mounted on the rear of the engine and is driven by a three-lobe cam on the camshaft. This high pressure fuel pump also regulates the fuel pressure using an actuator in the form of an internal solenoid-controlled valve. In order to keep the engine running efficiently under all operating conditions, the engine control module (ECM) requests pressure ranging from 2 - 15 MPa (290 - 2, 176 psi), depending on engine speed and load. Output drivers in the ECM provide the pump control circuit with a 12 V pulse-width modulated (PWM) signal, which regulates fuel pressure by closing and opening the control valve at specific times during pump strokes. This effectively regulates the portion of each pump stroke that is delivered to the fuel rail.

It is important to note that the high pressure fuel pump is a trailing-edge control system, meaning that if the control solenoid is NOT powered, the pump operates at maximum flow rate. In the event of pump control failure, the high pressure system is protected by a relief valve in the pump that prevents the pressure from exceeding 17.5 MPa (2, 538 psi).

NOTE: The fuel rail pressure sensor is diagnosed separately from the fuel pressure control system and should not be replaced for any codes referenced in this document.

The fuel rail fuel pressure sensor operates on a 5 V reference circuit and it provides the feedback necessary to the ECM to control the high pressure fuel pump and the fuel injectors.

Conditions for Running the DTC

• The ignition voltage is greater than 11 V.
• The engine speed is greater than 50 RPM.
• The DTCs run continuously within the enabling conditions.

Conditions for Setting the DTC

P0090

• The ECM detects an open circuit in the high pressure fuel pump actuator low control circuit.
• The DTC sets when the above condition is present for 4 s.

P0091

• The ECM detects a short to ground in the high pressure fuel pump actuator low control circuit.
• The DTC sets when the above condition is present for 4 s.

P0092

• The ECM detects a short to voltage in the high pressure fuel pump actuator low control circuit.
• The DTC sets when the above condition is present for 4 s.

P00C8

• The ECM detects an open circuit in the high pressure fuel pump actuator high control circuit.
• The DTC sets when the above condition is present for 4 s.

P00C9

• The ECM detects a short to ground in the high pressure fuel pump actuator high control circuit.
• The DTC sets when the above condition is present for 4 s.

P00CA

• The ECM detects a short to voltage in the high pressure fuel pump actuator high control circuit.
• The DTC sets when the above condition is present for 4 s.

Action Taken When the DTC Sets

• DTCs P0090, P0091, P0092, P00C8, P00C9, and P00CA are Type A DTCs.
• A message center or an indicator displays Reduced Engine Power.

Conditions for Clearing the DTC

• DTCs P0090, P0091, P0092, P00C8, P00C9, and P00CA are Type A DTCs.

Diagnostic Aids

• Before performing any circuit testing, ensure that the harness connector for the G18 High Pressure Fuel Pump is properly seated.
• Before performing any circuit testing, visually inspect the harness connector and the G18 High Pressure Fuel Pump connector for damage or bent pins.
• Circuit faults in the high pressure fuel control system may result in performance diagnostic failures, such as P0089, P00C6, P163A, P228C, or P228D. If any of the circuit DTCs referenced in this document are active, they take priority over any fuel system performance diagnostic.

  Always attempt to diagnose and repair circuit faults first, before reviewing other system DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0685 or P1682 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Command the Fuel Pressure Regulator ON and OFF with a scan tool while observing the following control circuit status parameters:

• Fuel Pressure Regulator Control Circuit High Voltage Test Status
• Fuel Pressure Regulator Control Circuit Open Test Status
• Fuel Pressure Regulator Control Circuit Low Voltage Test Status
• Fuel Pressure Regulator High Control Circuit High Voltage Test Status
• Fuel Pressure Regulator High Control Circuit Open Test Status
• Fuel Pressure Regulator High Control Circuit Low Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing

• Go to next step: If OK or Not Run is displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC does not set

6. All OK

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the G18 High Pressure Fuel Pump.

2. Ignition ON, verify that a test lamp does not illuminate between the high control circuit terminal 1 and ground and the low control circuit terminal 2 and ground.

• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the appropriate control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

3. Verify that a test lamp does not illuminate between the high control circuit terminal 1 and B+ and the low control circuit terminal 2 and B+.

• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the appropriate control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Connect a 3 A fused jumper wire between the high control circuit terminal 1 and ground.

5. Verify the Fuel Pressure Regulator High Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator High Control Circuit Low Voltage Test Status transitions from OK to Malfunction.

• The parameters do not change

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the high control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: The parameters change

6. Connect a 3 A fused jumper wire between the low control circuit terminal 2 and B+.

7. Verify the Fuel Pressure Regulator Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator Control Circuit High Voltage Test Status transitions from OK to Malfunction.

• The parameters do not change

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: The parameters change

8. Test or replace the G18 High Pressure Fuel Pump.

Component Testing

1. Ignition OFF, disconnect the harness connector at the G18 High Pressure Fuel Pump.

NOTE: The DMM and test leads must be calibrated to 0 Ω in order to prevent misdiagnosis.

2. Test for 0.3 - 0.7 Ω at 20ºC (68ºF) between the high control circuit terminal 1 and the low control circuit terminal 2.

• If not between 0.3 - 0.7 Ω

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If between 0.3 - 0.7 Ω

3. Test for infinite resistance between each terminal and the G18 High Pressure Fuel Pump housing.

• If less than infinite resistance

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If infinite resistance

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Pump Replacement
• Control Module References for K20 Engine Control Module replacement, setup, and programming
• Perform the Fuel Rail Pressure Relief Valve Reset procedure, if supported on the scan tool.

DTC P0096 or P0111

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0096

Intake Air Temperature (IAT) Sensor 2 Performance

DTC P0111

Intake Air Temperature (IAT) Sensor 1 Performance

Diagnostic Fault Information

IAT Sensor 1

IAT Sensor 2

Typical Scan Tool Data

IAT Sensor 1

IAT Sensor 2

Circuit/System Description

The intake air temperature (IAT) sensor 1 is a variable resistor that measures the temperature of the air in the sensor bore. The engine control module (ECM) supplies 5 V to the IAT sensor 1 signal circuit and a ground for the IAT sensor 1 low reference circuit. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF).

The IAT sensor 2 produces a frequency signal based on the inlet air temperature very close to the humidity sensor within the sensor bore. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF) and Hertz (Hz). The ECM applies 5 V to the circuit. The signal circuit is shared by the IAT sensor 2 and the humidity sensor. Ignition voltage and ground circuits are also supplied to the multifunction intake air sensor's internal circuits for these sensors:

• IAT sensor 2
• Humidity sensor
• MAF sensor

The multifunction intake air sensor houses the following:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• MAF sensor
• BARO pressure sensor

IAT Sensor 1 - Temperature, Resistance, Voltage Table

IAT Sensor 2 - Temperature, Frequency Table

Conditions for Running the DTCs

P0096 and P0111

• DTCs P0097, P0098, P0112, P0113, P0117, P0118, P0119, or P1682 are not set.
• The vehicle has been OFF at least 8 hours.
• Ignition 1 voltage is at least 11 V.
• These DTCs run once per ignition cycle when the enabling conditions are met.

Conditions for Setting the DTCs

P0096

• The ECM determines the absolute difference between IAT sensor 1 start-up temperature and the IAT sensor 2 start-up temperature is greater than 30ºC (54ºF).

AND

• The absolute difference between ECT start-up temperature and the IAT sensor 2 start-up temperature is greater or equal to the absolute difference between ECT start-up temperature and the IAT sensor 1 start-up temperature.
• This DTC runs once per ignition cycle when the enabling conditions are met.

P0111

• The ECM determines the absolute difference between IAT sensor 1 start-up temperature and the IAT sensor 2 start-up temperature is greater than 30ºC (54ºF).

AND

• The absolute difference between ECT start-up temperature and the IAT sensor 1 start-up temperature is greater or equal to the absolute difference between ECT start-up temperature and the IAT 2 start-up temperature.
• This DTC runs once per ignition cycle when the enabling conditions are met.

Action Taken When the DTC Sets

• DTC P0096 is a Type B DTC - North America and Korea.
• DTC P0096 is a Type C DTC - Except North America and Korea.
• DTC P0111 is a Type B DTC.
• The ECM commands the cooling fans ON.

Conditions for Clearing the DTCs

• DTC P0096 is a Type B DTC - North America and Korea.
• DTC P0096 is a Type C DTC - Except North America and Korea.
• DTC P0111 is a Type B DTC.

Diagnostic Aids

The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the IAT Sensor 2 parameter displays the values: 10 Hz; -40ºC (-40ºF), and there are also Humidity Sensor DTCs, check for a circuit problem.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 3 and 4 of this verification procedure only if the ignition has been OFF for 8 hours or more.

3. Ignition ON.

4. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

5. Engine idling, verify the following scan tool parameters are between: -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not between: -38 and +149ºC (-36 and +300ºF)

Refer to Circuit/System Testing.

• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

6. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Check the integrity of the entire air induction system and verify that none of the following conditions exist:

• A loose or disconnected charge air cooler hose or pipe; where equipped
• A blocked or obstructed charge air cooler, including: after-market grill covers; where equipped
• Any snow or ice build-up at the charge air cooler in cold climates; where equipped
• Any mud or dirt build-up at the charge air cooler; where equipped
• A restricted or collapsed air intake duct
• An intake manifold leak
• A MAP sensor seal that is leaking, missing, or damaged
• A restricted or collapsed air intake duct
• A misaligned or damaged air intake duct
• Any water intrusion in the induction system
• An Intake Manifold Resonator with a leaking seal, or a cracked or broken housing
• If a condition exists

Repair or replace component as appropriate.

• Go to next step: If no condition exists

2. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air sensor.

3. Test for less than 2 Ω between the low reference circuit terminal 3 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

4. Ignition OFF, all vehicle systems OFF, test for less than 2 Ω between the ground circuit terminal 7 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 2 Ω

5. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

6. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature sensor 1 signal circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

7. Ignition ON, verify the scan tool IAT Sensor 1 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

8. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 3.

9. Verify the scan tool IAT Sensor 1 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

10. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature sensor 2 signal circuit terminal 8 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

11. Determine if EL-38522-A Variable Signal Generator or equivalent is available.

• EL-38522-A, Variable Signal Generator; or equivalent is not available

1. Test or replace the B75C Multifunction Intake Air sensor.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
3. Verify the DTC does not set.
   • If the DTC sets

     Replace the K20 Engine Control Module.

   • Go to next step: If no DTCs set
4. All OK.

• Go to next step: EL-38522-A, Variable Signal Generator; or equivalent is available

12. Ignition OFF, connect the leads of the EL-38522-A Variable Signal Generator as follows:

• Red lead to the signal circuit terminal 8 at the harness connector
• Black leads to ground
• Battery voltage supply lead to B+

13. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Duty Cycle switch to 50 % (Normal)
• Frequency switch to 30 Hz

14. Ignition ON, verify the scan tool IAT Sensor 2 parameter is between 28 - 32 Hz.

• If not between 28 - 32 Hz

Replace the K20 Engine Control Module.

• Go to next step: If between 28 - 32 Hz

15. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

16. Test for less than 2 Ω between the intake air temperature sensor 3 low reference circuit terminal 1 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

17. Ignition ON, test for 4.8 - 5.2 V between the signal circuit terminal 2 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

18. Ignition ON, verify the scan tool IAT Sensor 3 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 2 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

19. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 2 and the low reference circuit terminal 1.

20. Verify the scan tool IAT Sensor 3 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

21. Test or replace the appropriate temperature sensor.

Component Testing

Multifunction Intake Air Sensor

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air Sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 1 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Hitachi Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

3. All OK.

Multifunction Intake Air Sensor

1. Test the IAT Sensor 2 by varying the sensor temperature while monitoring the air temperature with a thermometer. Compare the readings with the scan tool IAT Sensor 2 parameter. The values should be within 5%.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

2. All OK.

Turbocharger Boost/Intake Air Temperature sensor

1. Ignition OFF, disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 3 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Delco Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B111B Turbocharger Boost/Intake Air Temperature sensor.

• Go to next step: If within the specified range

3. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Intake Air Pressure and Temperature Sensor Replacement for turbocharger boost/intake air temperature sensor replacement
• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0097, P0098, or P0099

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0097

Intake Air Temperature (IAT) Sensor 2 Circuit Low Voltage

DTC P0098

Intake Air Temperature (IAT) Sensor 2 Circuit High Voltage

DTC P0099

Intake Air Temperature (IAT) Sensor 2 Circuit Intermittent

Diagnostic Fault Information

IAT Sensor 2

Typical Scan Tool Data

IAT Sensor 2

Circuit/System Description

The intake air temperature (IAT) sensor 1 is a variable resistor that measures the temperature of the air in the sensor bore. The engine control module (ECM) supplies 5 V to the IAT sensor 1 signal circuit and a ground for the IAT sensor 1 low reference circuit. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF).

The IAT sensor 2 produces a frequency signal based on the inlet air temperature very close to the humidity sensor within the sensor bore. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF) and Hertz (Hz). The ECM applies 5 V to the circuit. The signal circuit is shared by the IAT sensor 2 and the humidity sensor. Ignition voltage and ground circuits are also supplied to the multifunction intake air sensor's internal circuits for these sensors:

• IAT sensor 2
• Humidity sensor
• Mass Air Flow (MAF) sensor

The multifunction intake air sensor houses the following:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• MAF sensor
• BARO pressure sensor

IAT Sensor 1 - Temperature, Resistance, Voltage Table

IAT Sensor 2 - Temperature, Frequency Table

Conditions for Running the DTCs

P0097, P0098, and P0099

• The ignition is ON, or the engine is running.
• The Ignition 1 voltage is at least 11 V.
• The DTCs run continuously within the enabling conditions.
• Where P0099 is used, the DTC runs continuously within the enabling conditions.

Conditions for Setting the DTCs

P0097

NOTE: The scan tool display range is between -40 and +150ºC (-40 and +302ºF).

The ECM detects that the IAT sensor 2 signal is less than 13 Hz, colder than -60ºC (-76ºF), for greater than 5 s.

P0098

The ECM detects that the IAT sensor 2 signal is greater than 390 Hz, warmer than 150ºC (302ºF), for greater than 5 s.

P0099

Where P0099 used, the ECM detects that the IAT sensor 2 signal is intermittent or has abruptly changed for longer than 5 s.

Action Taken When the DTC Sets

• DTCs P0097, P0098, and P0099 are Type B DTCs - North America and Korea.
• DTCs P0097, P0098, and P0099 are Type C DTCs - Except North America and Korea.
• The ECM commands the cooling fans ON.

Conditions for Clearing the MIL/DTC

• DTCs P0097, P0098, and P0099 are Type B DTCs - North America and Korea.
• DTCs P0097, P0098, and P0099 are Type C DTCs - Except North America and Korea.

Diagnostic Aids

• With the ignition ON, the engine OFF, if the engine is cold, a properly functioning IAT sensor 2 will gradually increase the scan tool IAT Sensor 2 parameter. This is due to the heat that is generated by the MAF sensor heating elements.
• The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the IAT Sensor 2 parameter displays the values: 10 Hz; -40ºC (-40ºF), and there are also Humidity Sensor DTCs, check for a circuit problem.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 3 and 4 of this verification procedure only if the ignition has been OFF for 8 hours or more.

3. Ignition ON.

4. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

5. Engine idling, verify the following scan tool parameters are between: between -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not between: -38 and +149ºC (-36 and +300ºF)

Refer to Circuit/System Testing.

• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

6. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air sensor.

2. Test for less than 2 Ω between the low reference circuit terminal 3 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

3. Ignition OFF, all vehicle systems OFF, test for less than 2 Ω between the ground circuit terminal 7 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 2 Ω

4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

5. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature sensor 2 signal circuit terminal 8 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Determine if EL-38522-A Variable Signal Generator or equivalent is available.

• EL-38522-A, Variable Signal Generator; or equivalent is not available

1. Test or replace the B75C Multifunction Intake Air sensor.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
3. Verify the DTC does not set.

• If the DTC sets

Replace the K20 Engine Control Module.

• Go to next step: If no DTCs set

4. All OK.

• Go to next step: EL-38522-A, Variable Signal Generator; or equivalent is available

7. Ignition OFF, connect the leads of the EL-38522-A Variable Signal Generator as follows:

• Red lead to the signal circuit terminal 8 at the harness connector
• Black leads to ground
• Battery voltage supply lead to B+

8. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Duty Cycle switch to 50 % (Normal)
• Frequency switch to 30 Hz

9. Ignition ON, verify the scan tool IAT Sensor 2 parameter is between 28 - 32 Hz.

• If not between 28 - 32 Hz

Replace the K20 Engine Control Module.

• Go to next step: If between 28 - 32 Hz

10. Test or replace the B75C Multifunction Intake Air sensor.

Component Testing

Multifunction Intake Air Sensor

1. Test the IAT Sensor 2 by varying the sensor temperature while monitoring the air temperature with a thermometer. Compare the readings with the scan tool IAT Sensor 2 parameter. The values should be within 5%.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

2. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup.

DTC P00C7 (LTG)

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P00C7

Intake Air Pressure Measurement System - Multiple Sensors Not Plausible

Circuit/System Description

The Intake Air Pressure Measurement System consists of 3 sensors, the barometric pressure (BARO) sensor, the manifold absolute pressure (MAP) sensor, and the Turbocharger Boost sensor.

Conditions for Running the DTC

• DTCs P0106, P0107, P0108, P0237, P0238, P2227, P2228, P2229, P2230 or P2610 are not set.
• The engine is not running.
• Time between current ignition cycle and the last time the engine was running is greater than 10 s.
• Manifold pressure between 50 - 115 kPa (7.25 - 16.68 PSI).
• BARO pressure between 50 - 115 kPa (7.25 - 16.68 PSI).
• Turbocharger boost pressure between 50 - 115 kPa (7.25 - 16.68 PSI).
• This DTC runs continuously within the enabling conditions.

Conditions for Setting the DTC

The ECM detects an inconsistency between pressure sensors in the induction system in which a particular sensor cannot be identified as the failed sensor. The difference is greater than 10 kPa (1.5 PSI).

Action Taken When the DTC Sets

DTC P00C7 is a Type B DTC.

Conditions for Clearing the DTC

DTC P00C7 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify that DTCs P0106, P0107, P0236, P0237, P0238, P2227, P2228, P2229 or P2230 are not set.

• If any of the DTCs are set

If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs is set

3. Ignition ON, verify the following scan tool parameters are within range of the Altitude vs.

Barometric Pressure table. Refer to: Altitude Versus Barometric Pressure table.

• BARO Sensor
• MAP Sensor
• Turbocharger Boost Sensor
• If a sensor parameter is not within range

Refer to the appropriate diagnostic below for further diagnosis.

• Barometric Pressure (BARO) Sensor. Refer to: DTC P2227-P2230
• Manifold Absolute Pressure (MAP) Sensor. Refer to: DTC P0106
• Turbocharger Boost Pressure Sensor. Refer to: DTC P0236
• Go to next step: If all sensor parameters are within range

4. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for ECM replacement, programming and setup

DTC P00E9

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P00E9

Intake Air Temperature (IAT) Sensor 3 Circuit Performance

Diagnostic Fault Information

IAT Sensor 3

Typical Scan Tool Data

IAT Sensor 3

Circuit/System Description

The intake air temperature (IAT) sensor 3 is a variable resistor that changes an engine control module (ECM) supplied 5 V signal. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF). The IAT sensor 3 is integrated with the B111B Turbocharger Boost/Intake Air Temperature sensor. The ECM provides a ground for the IAT sensor 3 low reference circuit.

IAT Sensor 3 - Temperature, Resistance, Voltage Table

Conditions for Running the DTC

P00E9

• DTCs P0097, P0098, P0112, P0113, P0117, P0118, P0119, P00EA, or P00EB are not set.
• The vehicle has been OFF at least 8 hours.
• Ignition voltage is at least 11 V.
• These DTCs run once per ignition cycle when the enabling conditions are met.

Conditions for Setting the DTC

P00E9 - Condition 1

• The ECM determines the absolute difference between IAT sensor 1 start-up temperature and the IAT sensor 2 start-up temperature is less or equal to 30ºC (54ºF).

AND

• The ECM determines the absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 1 start-up temperature is greater than 25ºC (77ºF).

AND

• The ECM determines the absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 2 start-up temperature is greater than 25ºC (77ºF).

P00E9 - Condition 2

• The ECM determines the IAT sensor 1 start-up temperature is between the IAT sensor 3 start-up temperature and the IAT sensor 2 start-up temperature

AND

• The ECM determines the absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 2 start-up temperature is greater than 25ºC (77ºF).

AND

• The absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 1 start-up temperature is greater than the absolute difference between IAT sensor 2 start-up temperature and the IAT sensor 1 start-up temperature.

P00E9 - Condition 3

• The ECM determines the IAT sensor 2 start-up temperature is between the IAT sensor 3 start-up temperature and the IAT sensor 1 start-up temperature

AND

• The ECM determines the absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 1 start-up temperature is greater than 25ºC (77ºF).

AND

• The absolute difference between IAT sensor 3 start-up temperature and the IAT sensor 2 start-up temperature is greater than the absolute difference between IAT sensor 2 start-up temperature and the IAT sensor 1 start-up temperature.

Action Taken When the DTC Sets

DTC P00E9 is a Type B DTC.

Conditions for Clearing the DTCs

DTC P00E9 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0641, P0651, P0697, or P06A3 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 3 and 4 of this verification procedure only if the ignition has been OFF for 8 hours or more.

3. Ignition ON.

4. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

5. Engine idling, verify the following scan tool parameters are between: -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3
• If not between: -38 and +149ºC (-36 and +300ºF)
• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

6. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

7. Verify the DTC does not set.

• If the DTC sets
• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Check the integrity of the entire air induction system and verify that none of the following conditions exist:

• A loose or disconnected charge air cooler hose or pipe; where equipped
• A blocked or obstructed charge air cooler, including: after-market grill covers; where equipped
• Any snow or ice build-up at the charge air cooler in cold climates; where equipped
• Any mud or dirt build-up at the charge air cooler; where equipped
• A restricted or collapsed air intake duct
• An intake manifold leak
• A MAP sensor seal that is leaking, missing, or damaged
• A restricted or collapsed air intake duct
• A misaligned or damaged air intake duct
• Any water intrusion in the induction system
• An Intake Manifold Resonator with a leaking seal, or a cracked or broken housing
• If a condition exists

Repair or replace component as appropriate.

• Go to next step: If no condition exists

2. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air sensor.

3. Test for less than 2 Ω between the low reference circuit terminal 3 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

4. Ignition OFF, all vehicle systems OFF, test for less than 2 Ω between the ground circuit terminal 7 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 2 Ω

5. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

6. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature signal 1 circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

7. Ignition ON, verify the scan tool IAT Sensor 1 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

8. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 3.

9. Verify the scan tool IAT Sensor 1 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

10. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature sensor 2 signal circuit terminal 8 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

11. Determine if EL-38522-A Variable Signal Generator or equivalent is available.

• EL-38522-A, Variable Signal Generator; or equivalent is not available

1. Test or replace the B75C Multifunction Intake Air sensor.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
3. Verify the DTC does not set.
   • If the DTC sets

     Replace the K20 Engine Control Module.

   • Go to next step: If no DTCs set
4. All OK.

• Go to next step: EL-38522-A, Variable Signal Generator; or equivalent is available

12. Ignition OFF, connect the leads of the EL-38522-A Variable Signal Generator as follows:

• Red lead to the signal circuit terminal 8 at the harness connector
• Black leads to ground
• Battery voltage supply lead to B+

13. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Duty Cycle switch to 50 % (Normal)
• Frequency switch to 30 Hz

14. Ignition ON, verify the scan tool IAT Sensor 2 parameter is between 28 - 32 Hz.

• If not between 28 - 32 Hz

Replace the K20 Engine Control Module.

• Go to next step: If between 28 - 32 Hz

15. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

16. Test for less than 2 Ω between the low reference circuit terminal 1 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

17. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature signal 3 signal circuit terminal 2 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

18. Ignition ON, verify the scan tool IAT Sensor 3 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 2 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

19. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 2 and the low reference circuit terminal 1.

20. Verify the scan tool IAT Sensor 3 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   1. If 2 Ω or greater, repair the open/high resistance in the circuit.
   2. If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

21. Test or replace the appropriate sensor.

Component Testing

Multifunction Intake Air Sensor

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air Sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 1 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Hitachi Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

3. All OK.

Multifunction Intake Air Sensor

1. Test the IAT Sensor 2 by varying the sensor temperature while monitoring the air temperature with a thermometer. Compare the readings with the scan tool IAT Sensor 2 parameter. The values should be within 5%.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

2. All OK.

Turbocharger Boost/Intake Air Temperature sensor

1. Ignition OFF, disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 3 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Delco Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B111B Turbocharger Boost/Intake Air Temperature sensor.

• Go to next step: If within the specified range

3. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Intake Air Pressure and Temperature Sensor Replacement for turbocharger boost/intake air temperature sensor replacement
• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P00EA-P00EC

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P00EA

Intake Air Temperature (IAT) Sensor 3 Circuit Low Voltage

DTC P00EB

Intake Air Temperature (IAT) Sensor 3 Circuit High Voltage

DTC P00EC

Intake Air Temperature (IAT) Sensor 3 Circuit Erratic

Diagnostic Fault Information

IAT Sensor 3

Typical Scan Tool Data

IAT Sensor 3

Circuit/System Description

The intake air temperature (IAT) sensor 3 is a variable resistor that changes an engine control module (ECM) supplied 5 V signal. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF). The IAT sensor 3 is integrated with the B111B Turbocharger Boost/Intake Air Temperature sensor. The ECM provides a ground for the IAT sensor 3 low reference circuit.

IAT Sensor 3 - Temperature, Resistance, Voltage Table

Conditions for Running the DTCs

P00EA, P00EB, and P00EC

• The ignition is ON, or the engine is running.
• The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P00EA

The ECM detects that the IAT sensor 3 signal is warmer than 149ºC (300ºF) for at least 5 s.

P00EB

The ECM detects that the IAT sensor 3 signal is colder than -60ºC (-76ºF) for at least 5 s.

NOTE: The scan tool display range is between -40 and +150ºC (-40 and +302ºF).

P00EC

The ECM detects that the IAT sensor 3 signal is intermittent or has abruptly changed for at least 5 s.

Action Taken When the DTCs Set

• DTCs P00EA, P00EB, and P00EC are Type B DTCs.
• The ECM commands the cooling fans ON.

Conditions for Clearing the DTCs

DTCs P00EA, P00EB, and P00EC are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0641, P0651, P0697, or P06A3 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 3 and 4 of this verification procedure only if the ignition has been OFF for 8 hours or more.

3. Ignition ON.

4. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

5. Engine idling, verify the following scan tool parameters are between: -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3
• If not between: -38 and +149ºC (-36 and +300ºF)

Refer to Circuit/System Testing.

• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

2. Test for less than 2 Ω between the intake air temperature sensor 3 low reference circuit terminal 1 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

3. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature signal 3 signal circuit terminal 2 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

4. Ignition ON, verify the scan tool IAT Sensor 3 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 2 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

5. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 2 and the low reference circuit terminal 1.

6. Verify the scan tool IAT Sensor 3 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

7. Test or replace the B111B Turbocharger Boost/Intake Air Temperature sensor.

Component Testing

Turbocharger Boost/Intake Air Temperature sensor

1. Ignition OFF, disconnect the harness connector at the B111B Turbocharger Boost/Intake Air Temperature sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 3 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Delco sensors. The resistance values should be in range of the table values.

• If not within the specified range.

Replace the B111B Turbocharger Boost/Intake Air Temperature sensor.

• Go to next step: If within the specified range.

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Intake Air Pressure and Temperature Sensor Replacement for B111B Turbocharger Boost/Intake Air Temperature sensor replacement
• Control Module References for control module replacement, programming, and setup.

DTC P00F4-P00F6

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P00F4

Intake Air Humidity Sensor Circuit Low Voltage

DTC P00F5

Intake Air Humidity Sensor Circuit High Voltage

DTC P00F6

Intake Air Humidity Sensor Circuit Erratic

Diagnostic Fault Information

Intake Air Humidity

IAT Sensor 2

Typical Scan Tool Data

Intake Air Humidity

IAT Sensor 2

Circuit/System Description

The sensors listed below are integrated within the Multifunction Intake Air sensor:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• MAF sensor
• BARO pressure sensor

The humidity sensor measures the ambient humidity of the air in the sensor bore. The signal varies with intake air humidity and is displayed by the scan tool as duty cycle %. The humidity sensor and the intake air temperature (IAT) sensor 2 share the same signal circuit. The ECM applies 5 V to the circuit.

Ignition voltage and ground circuits are supplied to the multifunction intake air sensor's internal circuits for these sensors:

• IAT sensor 2
• Humidity sensor
• MAF sensor

Conditions for Running the DTCs

P00F4, P00F5, and P00F6

• DTC P1682 is not active.
• The ignition is ON.
• The Ignition 1 voltage is at least 11 V for longer than 0.9 s.
• These DTCs run continuously within the enabling conditions.

Conditions for Setting the DTCs

P00F4

The ECM detects that the humidity sensor signal is less than or equal to 5 % for greater than 4 s.

P00F5

The ECM detects that the humidity sensor signal is greater than or equal to 95 % for greater than 4 s.

P00F6

The ECM monitors the humidity sensor signal every 0.1 s, to determine if the signal has changed more than 80 %. The DTC fails when the condition exists for longer than 4 s.

Action Taken When the DTC Sets

• DTCs P00F4, P00F5, and P00F6 are Type B DTCs - North America and Korea.
• DTCs P00F4, P00F5, and P00F6 are Type C DTCs - Except North America and Korea.

Conditions for Clearing the MIL/DTC

• DTCs P00F4, P00F5, and P00F6 are Type B DTCs - North America and Korea.
• DTCs P00F4, P00F5, and P00F6 are Type C DTCs - Except North America and Korea.

Diagnostic Aids

• The Intake Air Humidity Signal parameter displays the measured humidity within the air intake system and may differ from atmospheric humidity measured outside the air intake system.
• With the ignition ON, the engine OFF, if the engine is cold, a properly functioning humidity sensor will gradually increase the scan tool Intake Air Humidity Signal parameter. This is due to the heat that is generated by the multifunction intake air sensor heating elements.
• The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the Intake Air Humidity parameter displays the value: 0% or 100%, and there are also IAT Sensor 2 DTCs, check for a circuit problem.
• With the ignition ON, the engine OFF, if the engine is cold, a properly functioning IAT sensor 2 will gradually increase the scan tool IAT Sensor 2 parameter. This is due to the heat that is generated by the multifunction intake air sensor heating elements.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 1 and 2 of this verification procedure only if the ignition has been OFF for 8 hours or more.

1. Ignition ON.

2. Verify the following scan tool parameters are within 25ºC (45ºF) of each other.

• Start-Up IAT Sensor 1
• Start-Up IAT Sensor 2
• Start-Up IAT Sensor 3; where equipped
• If not within 25ºC (45ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 25ºC (45ºF)

3. Engine idling, verify the scan tool Intake Air Humidity parameter is between 5 and 90 %.

• If not between 5 and 90 %

Refer to Circuit/System Testing.

• Go to next step: If between 5 and 90 %

4. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air sensor (Humidity Sensor).

2. Test for less than 5 Ω between the ground circuit terminal 7 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

NOTE:

• The IAT 2 parameter and the Intake Air Humidity Sensor parameter share the same signal circuit.
• The intake air temperature sensor 2 signal circuit is pulled up with low current voltage within the controller. Normally, a voltage can be measured on the circuit with a DMM, but the current will not be high enough to illuminate a test lamp.

4. Ignition On/Vehicle in Service Mode, verify the scan tool Intake Air Humidity Sensor parameter is less than 1%.

• If 1% or greater

1. Vehicle OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the IAT 2 signal circuit terminal 8 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If less than 1%

5. Vehicle OFF, install a 3 A fused jumper wire between the IAT 2 signal circuit terminal 8 and the low reference circuit terminal 3, Ignition On/Vehicle in Service Mode.

6. Verify the scan tool Intake Air Humidity Sensor parameter is greater than 99%.

• If 99% or less

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Vehicle OFF, remove the jumper wire and disconnect the harness connector at the K20 Engine Control Module, Ignition On/Vehicle in Service Mode.
2. Test for less than 1 V between the IAT 2 signal circuit terminal 8 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V.
3. Vehicle OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 99%

7. Test or replace the B75C Multifunction Intake Air sensor (IAT 2 Humidity Sensor).

Component Testing

Multifunction Intake Air Sensor

1. Test the Intake Air Humidity Sensor by varying the air humidity in the intake duct near the sensor, while observing the scan tool Intake Air Humidity Sensor parameter. The parameter should change and be within 5 - 95%.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

2. All OK.

IAT 2 Circuit Testing with EL-38522-A

NOTE: In-correct diagnosis will result if Circuit/System Testing is not completed before performing the following test.

1. Perform the following test using a EL-38522-A Variable Signal Generator or equivalent, if available.

2. Vehicle Off, connect the leads of the EL-38522-A Variable Signal Generator as follows:

1. Red lead to the signal circuit terminal 8 at the harness connector
2. Black leads to ground
3. Battery voltage supply lead to B+

3. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Duty Cycle switch to 50 % (Normal)
• Frequency switch to 250 Hz

4. Ignition On/Vehicle in Service Mode.

5. Verify the scan tool IAT Sensor 2 parameters listed below are within the ranges listed below:

• IAT Sensor 2 is between 248 - 252 Hz

NOTE: Changing the frequency should cause a warmer or colder IAT 2 temperature.

• IAT Sensor 2 is between 70 - 76ºC (160 - 166ºF)

NOTE: Increasing or decreasing the duty cycle should have an inverse affect on humidity.

• Intake Air Humidity Sensor is between 48 - 52%
• If a parameter is not within the specified range

1. Vehicle Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If all the parameters are within the specified range

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for Engine Control Module replacement, programming, and setup.

DTC P0101

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0101

Mass Air Flow (MAF) Sensor Performance

Diagnostic Fault Information

Typical Scan Tool Data

MAF Sensor

Circuit Description

The intake flow rationality diagnostic provides the within-range rationality check for the mass air flow (MAF), manifold absolute pressure (MAP), and the throttle position sensors. This is an explicit modelbased diagnostic containing 4 separate models for the intake system.

The estimates of MAF and MAP obtained from this system of models and calculations are then compared to the actual measured values from the MAF, MAP, and the throttle position sensors and to each other to determine the appropriate DTC to fail.

Conditions for Running the DTCs

• DTC P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0116, P0117, P0118, P0128, P0335, or P0336 is not set
• The engine speed is between 575 - 6, 600 RPM.
• The engine coolant temperature (ECT) is between -7 to +129ºC (+19 to +264ºF).
• The intake air temperature (IAT) is between -20 and +125ºC (-4 and +257ºF).
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

The engine control module (ECM) detects that the actual measured airflow from the MAF, MAP, and throttle position sensors is not within range of the calculated airflow that is derived from the system of models for greater than 2 s.

Action Taken When the DTC Sets

DTC P0101 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0101 is a Type B DTC.

Diagnostic Aids

• Any type of contamination on the MAF sensor heating elements will degrade the proper operation of the sensor. Certain types of contaminants act as a heat insulator, which will impair the response of the sensor to airflow changes. Water or snow can create the opposite effect, and cause the signal to increase rapidly.
• Certain aftermarket air filters may cause this DTC to set.
• Certain aftermarket air induction systems may cause this DTC to set.
• Modifications to the air induction system may cause this DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON, verify that DTC P0641, P0651, P0697, or P06A3 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

2. If you were sent here from DTC P0068, P0106, P0121, P0236, or P1101; refer to Circuit/System Testing.

3. Ignition ON, verify the scan tool Throttle Body Idle Airflow Compensation parameter is less than 90 %.

• 90 % or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90 %

4. Verify the scan tool Throttle Position Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Disagree

Refer to DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135 for further diagnosis.

• Go to next step: If Agree

5. Determine the current vehicle testing altitude.

6. Verify the scan tool MAP Sensor pressure parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the MAP Sensor parameter is not in range

Refer to DTC P0106 for further diagnosis.

• Go to next step: If the MAP Sensor parameter is within range

7. Verify the engine is equipped with a turbocharger.

• If not equipped with a turbocharger

Refer to Step 10.

• Go to next step: If equipped with a turbocharger

8. Verify the scan tool Boost Pressure Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the Boost Pressure Sensor parameter is not in range

Refer to DTC P0236 for further diagnosis.

• Go to next step: If the Boost Pressure Sensor parameter is within range

9. Engine idling.

10. Verify the scan tool Boost Pressure Sensor parameter increases with accelerator pedal input.

• If the Boost Pressure Sensor parameter does not increase

Refer to DTC P0236 for further diagnosis.

• Go to next step: If the Boost Pressure Sensor parameter does increase

11. Verify the scan tool MAP Sensor pressure parameter is between 26 - 52 kPa (3.8 - 7.5 PSI) and changes with accelerator pedal input.

• If not between 26 - 52 kPa (3.8 - 7.5 PSI) or does not change

Refer to DTC P0106 for further diagnosis.

• Go to next step: If between 26 - 52 kPa (3.8 - 7.5 PSI) and changes

12. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3, 000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• If the MAF Sensor parameter does not change smoothly and gradually

Refer to Circuit/System Testing.

• Go to next step: If the MAF Sensor parameter changes smoothly and gradually

13. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

14. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

15. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Verify the integrity of the entire air induction system by verifying that none of the following conditions exist:

• Any damaged components
• Improper operation of turbocharger wastegate actuator or bypass valve; where equipped
• Improperly installed components
• Collapsed, restricted, or damaged components
• Loose clamps, cracks, or other damage
• An air flow restriction
• Restricted air filter
• Splits, kinks, leaks, or improper connections at the vacuum hoses
• Vacuum leaks at the intake manifold, MAP sensor, and throttle body
• Water intrusion
• Any snow or ice buildup, in cold climates
• Contamination of the Mass Air Flow sensor element
• If a condition is found

Repair or replace component as appropriate.

• Go to next step: If no condition is found

2. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air sensor.

3. Test for less than 2 Ω between the ground circuit terminal 7 and ground.

• If 2 Ω or greater

1. Ignition OFF.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 2 Ω

4. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

5. Ignition ON, test for 4.8 - 5.2 volts between the signal circuit terminal 6 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Determine if EL-38522-A Variable Signal Generator or equivalent is available.

• EL-38522-A, Variable Signal Generator; or equivalent is not available

1. Test or replace the B75C Multifunction Intake Air sensor.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
3. Verify the DTC does not set.

• If the DTC sets

Replace the K20 Engine Control Module.

• Go to next step: If no DTCs set

4. All OK.

• Go to next step: EL-38522-A, Variable Signal Generator; or equivalent is available

7. Ignition OFF, connect the leads of the EL-38522-A Variable Signal Generator as follows:

• Red lead to the signal circuit terminal 6 at the harness connector
• Black leads to ground
• Battery voltage supply lead to B+

8. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Frequency switch to 5 kHz
• Duty Cycle switch to 50 % (Normal)

9. Engine idling, observe the scan tool MAF Sensor parameter. The scan tool MAF Sensor parameter should be between 4, 950 - 5, 050 Hz.

• If not between 4, 950 - 5, 050 Hz.

Replace the K20 Engine Control Module.

• Go to next step: If between 4, 950 - 5, 050 Hz.

10. Test or replace the B75C Multifunction Intake Air sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0102 or P0103

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0102

Mass Air Flow (MAF) Sensor Circuit Low Frequency

DTC P0103

Mass Air Flow (MAF) Sensor Circuit High Frequency

Diagnostic Fault Information

Typical Scan Tool Data

MAF Sensor

Circuit/System Description

The mass air flow (MAF) sensor is integrated with the multifunction intake air sensor. The MAF sensor is an air flow meter that measures the amount of air in the sensor bore. The engine control module (ECM) uses the MAF sensor signal to provide the correct fuel delivery for all engine speeds and loads.

A small quantity of air entering the engine indicates a deceleration or idle condition. A large quantity of air entering the engine indicates an acceleration or high load condition.

The ECM applies 5 V to the MAF sensor on the MAF sensor signal circuit. The sensor uses the voltage to produce a variable frequency signal based on the inlet air flow through the sensor bore. The signal varies with engine load and is displayed by the scan tool as Hertz (Hz) and grams per second (g/s).

Ignition voltage and ground circuits are also supplied to the multifunction intake air sensor's internal circuits for these sensors:

• Intake Air Temperature (IAT) sensor 2
• Humidity sensor
• MAF sensor

The multifunction intake air sensor houses the following:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• MAF sensor
• BARO pressure sensor

Conditions for Running the DTC

• The engine is running for at least 1 s.
• The engine speed is at least 300 RPM.
• The ignition signal is at least 11 V.
• The above conditions are met for at least 1 s.
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

P0102

The ECM detects that the MAF Sensor signal parameter is less than 500 Hz (about 0.25 g/s) for at least 250 cylinder firing events.

P0103

The ECM detects that the MAF Sensor signal parameter is at least 11, 000 Hz (about 328 g/s) for at least 250 cylinder firing events.

Action Taken When the DTCs Set

DTCs P0102 and P0103 are Type B DTCs.

Conditions for Clearing the MIL/DTCs

DTCs P0102 and P0103 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Engine idling, observe the scan tool MAF Sensor parameter. The reading should be between 2.5 - 5.5 g/s.

• If not between 2.5 - 5.5 g/s

Refer to Circuit/System Testing.

• Go to next step: If between 2.5 - 5.5 g/s

2. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3, 000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• The MAF Sensor parameter does not change smoothly and gradually

Refer to Circuit/System Testing.

• Go to next step: The MAF Sensor parameter changes smoothly and gradually

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

5. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air sensor.

2. Test for less than 2 Ω between the ground circuit terminal 7 and ground.

• If 2 Ω or greater

1. Ignition OFF. Disconnect the sensor chassis ground.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the chassis ground connection.

• Go to next step: If less than 2 Ω

3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

4. Ignition ON, test for 4.8 - 5.2 volts between the signal circuit terminal 6 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Determine if EL-38522-A Variable Signal Generator or equivalent is available.

• EL-38522-A, Variable Signal Generator; or equivalent is not available

1. Test or replace the B75C Multifunction Intake Air sensor.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.
3. Verify the DTC does not set.

• If the DTC sets

Replace the K20 Engine Control Module.

• Go to next step: If no DTCs set

4. All OK.

6. Ignition OFF, connect the leads of the EL-38522-A Variable Signal Generator as follows:

• Red lead to the signal circuit terminal 6 at the harness connector
• Black leads to ground
• Battery voltage supply lead to B+

7. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Frequency switch to 5 kHz
• Duty Cycle switch to 50 % (Normal)

8. Engine idling, verify the scan tool MAF Sensor parameter is between 4, 950 - 5, 050 Hz.

• If not between 4, 950 - 5, 050 Hz.

Replace the K20 Engine Control Module.

• Go to next step: If between 4, 950 - 5, 050 Hz.

9. Test or replace the B75C Multifunction Intake Air sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0106

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0106

Manifold Absolute Pressure (MAP) Sensor Performance

Diagnostic Fault Information

Typical Scan Tool Data

MAP Sensor

MAP Sensor, if equipped with Turbocharger

Circuit Description

The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold.

Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, barometric pressure (BARO) and if equipped, turbocharger output. A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance.

The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5 V reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation the greatest pressure that can exist in the intake manifold is at ignition ON, engine OFF, which is equal to the BARO. If equipped, a turbocharger can increase the pressure above BARO, when the vehicle is operated at wide-open throttle (WOT). The lowest manifold pressure occurs when the vehicle is idling or decelerating. The ECM monitors the MAP sensor signal for pressure outside of the normal range.

Conditions for Running the DTC

• DTCs P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0128, P0335, P0336, P2227, P2228, P2229, and P2230 are not set.
• The engine speed is between 575 and 6, 600 RPM.
• The ECT Sensor is between -7 and +125ºC (+19 and +257ºF).
• The IAT Sensor is between -20 and +125ºC (-4 and +257ºF).
• This DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM determines if the MAP Sensor is not within the normal operating range. It accomplishes this by running 3 different models within the software to determine the values, for greater than 0.5 S.

Action Taken When the DTC Sets

DTC P0106 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0106 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

GE-23738-A Vacuum Pump

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. If you were sent here from DTC P0068, P0101, P0121, P0236, or P1101 refer to Circuit/System Testing.

4. Verify the scan tool Throttle Body Idle Airflow Compensation parameter is less than 90%.

• If 90% or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90%

5. Verify the scan tool Throttle Body Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Disagree

Refer to DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135 for further diagnosis.

• Go to next step: If Agree

6. Determine the current vehicle testing altitude.

7. Verify the scan tool MAP Sensor pressure parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the MAP Sensor parameter is not in range

Refer to Circuit/System Testing.

• Go to next step: If the MAP Sensor parameter is in range

8. Verify if the engine is equipped with a turbocharger.

• If not equipped with a turbocharger

Refer to Step 12.

• Go to next step: If equipped with a turbocharger

9. Verify the scan tool Boost Pressure Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the Boost Pressure Sensor parameter is not in range

Refer to DTC P0236 for further diagnosis.

• Go to next step: If the Boost Pressure Sensor parameter is within range

10. Verify the scan tool Boost Pressure Sensor parameter decreases after starting the engine.

• If the Boost Pressure Sensor parameter does not decrease

Refer to DTC P0236 for further diagnosis.

• Go to next step: If the Boost Pressure Sensor parameter does decrease

11. Engine idling.

12. Verify the scan tool MAP Sensor pressure parameter is between 26 - 52 kPa (3.8 - 7.5 PSI) and changes with accelerator pedal input.

• If not between 26 - 52 kPa (3.8 - 7.5 PSI) or does not change

Refer to Circuit/System Testing.

• Go to next step: If between 26 - 52 kPa (3.8 - 7.5 PSI) and changes

13. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• The MAF Sensor parameter does not change smoothly and gradually

Refer to DTC P0101 for further diagnosis.

• Go to next step: The MAF Sensor parameter changes smoothly and gradually

14. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

15. Verify a DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

16. All OK.

Circuit/System Testing

1. Verify the integrity of the entire air induction system and verify that none of the following conditions exist:

• Any damaged components
• Improper operation of turbocharger wastegate actuator or bypass valve; if equipped
• Loose or improper installation of the turbocharger and the charge air cooler, including the flexible ductwork; if equipped
• An air flow restriction
• Any vacuum leak
• Improperly routed vacuum hoses
• A restriction in the MAP Sensor port, or the BARO port; where equipped
• Proper operation of the positive crankcase ventilation system
• Missing, restricted or leaking exhaust components. Refer to Symptoms - Engine Exhaust.
• Engine mechanical condition; for example: low compression or incorrect timing chain installation. Refer to Symptoms - Engine Mechanical.
• If a condition is found

If a condition is found, repair or replace the component as appropriate.

• Go to next step: If no condition is found

2. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down. Disconnect the harness connector at the B74 Manifold Absolute Pressure Sensor.

3. Test for less than 2 Ω between the low reference circuit terminal 2 and ground.

If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

Go to next step: If less than 2 Ω

4. Ignition ON.

5. test for 4.8 - 5.2 V between the 5 V reference circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

NOTE: If the signal circuit is shorted to a voltage the ECM or the MAP Sensor may be damaged.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Verify the scan tool MAP Sensor parameter is less than 0.5 V.

• If 0.5 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON
2. Test for less than 1 V between the signal circuit terminal 3 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.5 V

7. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 1.

8. Ignition ON, verify the scan tool MAP voltage parameter is greater than 4.5 V.

• If 4.5 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 3 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.5 V

9. Test or replace the B74 Manifold Absolute Pressure Sensor.

Component Testing

NOTE: You must perform the Circuit/System Testing in order to verify the integrity of the MAP Sensor circuits before proceeding with the Component Testing.

Skewed Sensor Test

1. Ignition OFF, remove the B74 Manifold Absolute Pressure Sensor from the engine. Connect the harness to the sensor, if disconnected.

2. Ignition ON.

3. Apply 17 kPa (5.0 in Hg) of vacuum to the B74 Manifold Absolute Pressure Sensor, with the GE- 23738-A.

4. Verify the scan tool MAP pressure parameter decreases between 13 - 21 kPa (1.8 - 3.0 PSI).

• If the parameter does not decrease between 13 - 21 kPa (1.8 - 3.0 PSI).

Replace the B74 Manifold Absolute Pressure Sensor.

• Go to next step: If the parameter does decrease between 13 - 21 kPa (1.8 - 3.0 PSI).

5. Apply 34 kPa (10.0 in Hg) of vacuum to the B74 Manifold Absolute Pressure Sensor, with the GE-23738-A.

6. Verify the scan tool MAP pressure parameter decreases between 30 - 38 kPa (4.4 - 5.5 PSI).

• If the parameter does not decrease between 30 - 38 kPa (4.4 - 5.5 PSI).

Replace the B74 Manifold Absolute Pressure Sensor.

• Go to next step: If the parameter does decrease between 30 - 38 kPa (4.4 - 5.5 PSI).

7. All OK.

Erratic Signal Test

1. Ignition OFF, remove the B74 Manifold Absolute Pressure Sensor and disconnect the harness.

2. Install a 3 A fused jumper wire between the 5 V reference circuit terminal 1 of the sensor and the sensor harness.

3. Install a jumper wire between the low reference circuit terminal 2 of the sensor and ground.

4. Install a jumper wire to the signal circuit terminal 3 of the sensor.

5. Connect a DMM between the jumper wire and ground.

6. Ignition ON, observe the DC voltage on the DMM. Slowly apply between 0 - 15 kPa (0 - 4.4 in Hg) of vacuum to the sensor with the GE-23738-A.

7. Verify the voltage changes, without any spikes or dropouts and is between 0.2 - 4.9 V.

• If not between 0.2 - 4.9 V or has spikes or dropouts

Replace the B74 Manifold Absolute Pressure Sensor.

• Go to next step: If between 0.2 - 4.9 V and there are no spikes or dropouts

8. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Control Module References for ECM replacement, programming, and setup
• Manifold Absolute Pressure Sensor Replacement.

DTC P0107 or P0108

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptors

DTC P0107

Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage

DTC P0108

Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

Diagnostic Fault Information

Typical Scan Tool Data

MAP Sensor

MAP Sensor, if equipped with Turbocharger

Circuit Description

The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold.

Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, barometric pressure (BARO) ; and if equipped turbocharger output. A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance.

The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5 V reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.

Under normal operation the greatest pressure that can exist in the intake manifold is at ignition ON, engine OFF, which is equal to the BARO. If equipped, a turbocharger can increase the pressure above BARO, when the vehicle is operated at wide-open throttle (WOT). The lowest manifold pressure occurs when the vehicle is idling or decelerating. The ECM monitors the MAP sensor signal for pressure outside of the normal range.

Conditions for Running the DTC

P0107

This DTC runs continuously.

P0108

This DTC runs continuously.

Conditions for Setting the DTC

P0107

The ECM detects that the MAP Sensor voltage is less than 0.15 V for more than 13 ms.

P0108

The ECM detects that the MAP Sensor voltage is more than 4.50 V for greater than 13 ms.

Action Taken When the DTC Sets

DTCs P0107 and P0108 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P0107 and P0108 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

GE-23738-A Vacuum Pump

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools)

Circuit/System Verification

1. Ignition ON, verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

2. Determine the current vehicle testing altitude.

3. Verify the scan tool MAP Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the MAP Sensor parameter is not in range

Refer to Circuit/System Testing for further diagnosis.

• Go to next step: If the MAP Sensor parameter is within range

4. Verify the engine is equipped with a turbocharger.

• If not equipped with a turbocharger

Refer to Step 6.

• Go to next step: If equipped with a turbocharger

5. Engine idling, verify the scan tool MAP Sensor voltage parameter is between 0.3 - 4.8 V and changes with accelerator pedal input.

• If not between 0.3 - 4.8 V or does not change

Refer to Circuit/System Testing.

• Go to next step: If between 0.3 - 4.8 V and changes

Go to next step: Refer to Step 7.

6. Engine idling, verify the scan tool MAP Sensor voltage parameter is between 0.2 - 4.5 V and changes with accelerator pedal input.

• If not between 0.2 - 4.5 V or does not change

Refer to Circuit/System Testing.

• Go to next step: If between 0.2 - 4.5 V and changes

7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

8. Verify the DTC does not set.

• If any DTC sets

Refer to Circuit/System Testing.

• Go to next step: If no DTC sets

9. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B74 Manifold Absolute Pressure Sensor.

2. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down. Test for less than 2 Ω between the low reference circuit terminal 2 and ground.

• If 2 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 2 Ω

3. Ignition ON, test for 4.8 - 5.2 V between the 5 V reference circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

NOTE: If the signal circuit is shorted to a voltage the ECM or the MAP Sensor may be damaged.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

4. Ignition ON, verify the scan tool MAP Sensor parameter is less than 0.5 V.

• If 0.5 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition ON, test for less than 1 V between the signal circuit terminal 3 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.5 V

5. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 1.

6. Ignition ON, verify the scan tool MAP Sensor voltage parameter is greater than 4.5 V.

• If 4.5 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Remove the jumper wire, test for infinite resistance between the signal circuit terminal 3 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.5 V

7. Test or replace the B74 Manifold Absolute Pressure Sensor.

Component Testing

NOTE: You must perform the Circuit/System Testing in order to verify the integrity of the MAP Sensor circuits before proceeding with the Component Testing.

Skewed Sensor Test

1. Ignition OFF, remove the B74 Manifold Absolute Pressure Sensor from the engine. Connect the harness to the sensor, if disconnected.

2. Ignition ON, apply 17 kPa (5.0 in Hg) of vacuum to the B74 Manifold Absolute Pressure Sensor, with the GE-23738-A. Verify the scan tool MAP pressure parameter decreases between 13 - 21 kPa (1.8 - 3.0 PSI).

• If the parameter does not decrease between 13 - 21 kPa (1.8 - 3.0 PSI)

Replace the B74 Manifold Absolute Pressure Sensor.

• Go to next step: If the parameter does decrease between 13 - 21 kPa (1.8 - 3.0 PSI)

3. Apply 34 kPa (10.0 in Hg) of vacuum to the B74 Manifold Absolute Pressure Sensor, with the GE-23738-A. Verify the scan tool MAP pressure parameter decreases between 30 - 38 kPa (4.4 - 5.5 PSI).

• If the parameter does not decrease between 30 - 38 kPa (4.4 - 5.5 PSI)

Replace the B74 Manifold Absolute Pressure Sensor.

• Go to next step: If the parameter does decrease between 30 - 38 kPa (4.4 - 5.5 PSI)

4. All OK.

Erratic Signal Test

1. Ignition OFF, remove the B74 Manifold Absolute Pressure Sensor and disconnect the harness.

2. Install a 3 A fused jumper wire between the 5 V reference circuit terminal 1 of the sensor and the sensor harness.

3. Install a jumper wire between the low reference circuit terminal 2 of the sensor and ground.

4. Install a jumper wire to the signal circuit terminal 3 of the sensor.

5. Connect a DMM between the jumper wire and ground.

6. Ignition ON, observe the DC voltage on the DMM. Slowly apply between 0-15 kPa (0 - 4.4 in Hg) of vacuum to the sensor with the GE-23738-A Vacuum Pump. Verify the voltage changes, without any spikes or dropouts and is between 0.2 - 4.9 V.

• If not between 0.2 - 4.9 V or has spikes or dropouts
  • Replace the B74 Manifold Absolute Pressure Sensor.
• Go to next step: If between 0.2 - 4.9 V and there are no spikes or dropouts

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Manifold Absolute Pressure Sensor Replacement.
• Control Module References for engine control module replacement, programming, and setup

DTC P0112, P0113, or P0114

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0112

Intake Air Temperature (IAT) Sensor 1 Circuit Low Voltage

DTC P0113

Intake Air Temperature (IAT) Sensor 1 Circuit High Voltage

DTC P0114

Intake Air Temperature (IAT) Sensor 1 Circuit Intermittent

Diagnostic Fault Information

IAT Sensor 1

Typical Scan Tool Data

IAT Sensor 1

Circuit/System Description

The intake air temperature (IAT) sensor 1 is a variable resistor that measures the temperature of the air in the sensor bore. The engine control module (ECM) supplies 5 V to the IAT sensor 1 signal circuit and a ground for the IAT sensor 1 low reference circuit. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF).

The multifunction intake air sensor houses the following:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• Mass Air Flow (MAF) sensor
• BARO pressure sensor

IAT Sensor 1 - Temperature, Resistance, Voltage Table

Conditions for Running the DTCs

P0112, P0113, and P0114

• The ignition is ON, or the engine is running.
• The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

NOTE: The scan tool display range is between -40 and +150ºC (-40 and +302ºF).

P0112

The ECM detects that the IAT sensor signal is warmer than 149ºC (300ºF) for at least 5 s.

P0113

The ECM detects that the IAT sensor signal is colder than -60ºC (-76ºF) for at least 5 s.

P0114

Where this DTC is used, the ECM detects that the IAT sensor signal is intermittent or has abruptly changed for at least 5 s.

Action Taken When the DTCs Set

• DTCs P0112, P0113, and P0114 are Type B DTCs.
• The ECM commands the cooling fans ON.

Conditions for Clearing the DTCs

DTCs P0112, P0113, and P0114 are Type B DTCs.

Diagnostic Aids

With the ignition ON, the engine OFF, if the engine is cold, a properly functioning IAT sensor 1 will gradually increase the scan tool IAT Sensor 1 parameter. This is due to the heat that is generated by the MAF sensor heating elements.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: To minimize the effects of residual engine heat and sensor internal heating elements, perform Steps 1 and 2 of this verification procedure only if the ignition has been OFF for 8 hours or more.

1. Ignition ON.

2. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

3. Engine idling, verify the following scan tool parameters are between: -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• IAT Sensor 3; where equipped
• If not between: -38 and +149ºC (-36 and +300ºF)

Refer to Circuit/System Testing.

• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

4. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air sensor.

2. Test for less than 5 Ω between the low reference circuit terminal 3 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 engine control module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 engine control module.

• Go to next step: If less than 5 Ω

3. Ignition ON, test for 4.8 - 5.2 V between the intake air temperature sensor 1 signal circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 engine control module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 engine control module.

• If greater than 5.2 V

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition OFF, disconnect the harness connector at the K20 engine control module.
2. Ignition ON, test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 engine control module.

• Go to next step: If between 4.8 - 5.2 V

4. Ignition ON, verify the scan tool IAT Sensor 1 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Modul

• Go to next step: If colder than -39ºC (-38ºF).

5. Ignition OFF, install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 3.

6. Verify the scan tool IAT Sensor 1 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

7. Test or replace the B75C Multifunction Intake Air sensor.

Component Testing

Multifunction Intake Air Sensor

1. Ignition OFF, disconnect the harness connector at the B75C Multifunction Intake Air Sensor.

NOTE: A thermometer can be used to test the sensor off the vehicle.

2. Test the IAT sensor 1 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Hitachi Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

3. All OK.

Repair Instructions

• Perform the Diagnostic Repair Verification after completing the repair.
• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup.

DTC P0117, P0118, or P0119

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0117

Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage

DTC P0118

Engine Coolant Temperature (ECT) Sensor Circuit High Voltage

DTC P0119

Engine Coolant Temperature (ECT) Sensor Circuit Intermittent

Diagnostic Fault Information

Typical Scan Tool Data

ECT Sensor

Circuit/System Description

For an overview of the component/system, refer to: Cooling System Description and Operation

Conditions for Running the DTC

P0117

• Ignition=On
• Frequency the DTC runs=Continuously - After the running conditions are met

P0118

• Engine=Running - For greater than 15 s
• IAT Sensor=Warmer than -7ºC (19ºF)

Frequency the DTC runs=Continuously - After the running conditions are met

P0119

DTC P0117, P0118 = Not set

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

P0117

Engine Coolant Temperature=Warmer than 149ºC (300ºF) - For greater than 5 s

P0118

Engine Coolant Temperature=Colder than -39ºC (-38ºF) - For greater than 5 s

P0119

Engine Coolant Temperature=Intermittent - For greater than 3 s

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type B DTC

• A/C Compressor=Off
• Cooling Fan=On
• Engine Coolant Temperature - Gauge=Inoperative

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type B DTC

Diagnostic Aids

After starting a cold engine, the following scan tool parameter value should rise steadily and then stabilize: ECT Sensor 1

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode

2. Verify the scan tool parameter: ECT Sensor=-39 to 149ºC (-38 to 300ºF)

• If not between -39 and 149ºC (-38 and 300ºF)

Refer to:Circuit/System Testing

• Go to next step: If between -39 and 149ºC (-38 and 300ºF)

3. Verify the scan tool parameter: ECT Sensor=The value should not spike or drop out.

Perform the action while monitoring the parameter:

• Wiggle the harness and connector: B34 Engine Coolant Temperature Sensor
• Wiggle the harness and connector: K20 Engine Control Module
• If the value spikes or drops out

Repair as necessary - Wiring / Terminal (s) / Electrical Connector (s)

• Go to next step: If the value does not spike or drop out

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set

5. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the electrical connector: B34 Engine Coolant Temperature Sensor.

3. Test for less than 10 ohms between the test points: Low Reference circuit terminal 2/B & Ground.

• If 10 ohms or greater

1. Disconnect the appropriate electrical connector: K20 Engine Control Module
2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 2/B@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If less than 10 ohms

4. Ignition - On / Vehicle - In Service Mode.

5. Verify the scan tool parameter: ECT Sensor=Colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF)

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 1/A@Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • If infinite resistance - Replace the component: K20 Engine Control Module

• Go to next step: If less than 10 ohms

4. Ignition - On / Vehicle - In Service Mode

5. Verify the scan tool parameter: ECT Sensor=Colder than -39ºC (-38ºF)

• If warmer than -39ºC (-38ºF)

1. Ignition/Vehicle - Off
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 1/A@Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • If infinite resistance - Replace the component: K20 Engine Control Module

• Go to next step: If colder than -39ºC (-38ºF)

6. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal 1/A & Low Reference circuit terminal 2/B.

7. Verify the scan tool parameter: ECT Sensor=Warmer than 149ºC (300ºF)

• If 149ºC (300ºF) or colder

1. Ignition/Vehicle - Off & Remove - Jumper wire (s)
2. Disconnect the appropriate electrical connector: K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 1/A@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
5. Ignition/Vehicle - Off
6. Test for less than 2 ohms between the test points: Signal circuit terminal 1/A@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If warmer than 149ºC (300ºF)

8. Test or replace the component: B34 Engine Coolant Temperature Sensor

Component Testing

1. Ignition/Vehicle - Off.

2. Disconnect the electrical connector: B34 Engine Coolant Temperature Sensor.

3. Test for 42 to 78, 834 ohms between the test points: Signal terminal 1/A & Low Reference terminal 2/B.

• If not between 42 and 78, 834 ohms

Replace the component: B34 Engine Coolant Temperature Sensor

• Go to next step: If between 42 and 78, 834 ohms

4. Verify the value is within the range listed in the table: Temperature Versus Resistance - Engine Coolant Temperature Sensor

• If not in the specified range

Replace the component: B34 Engine Coolant Temperature Sensor

• Go to next step: If in the specified range

5. Test for infinite resistance between the test points: Each terminal of the component & The component's housing

• If less than infinite resistance

Replace the component: B34 Engine Coolant Temperature Sensor

• Go to next step: If infinite resistance

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Engine Coolant Temperature Sensor Replacement
• For control module replacement, programming, and setup refer to: Control Module References

DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0121

Throttle Position Sensor 1 Performance

DTC P0122

Throttle Position Sensor 1 Circuit Low Voltage

DTC P0123

Throttle Position Sensor 1 Circuit High Voltage

DTC P0222

Throttle Position Sensor 2 Circuit Low Voltage

DTC P0223

Throttle Position Sensor 2 Circuit High Voltage

DTC P16A0

Sensor Communication Circuit Low Voltage

DTC P16A1

Sensor Communication Circuit High Voltage

DTC P16A2

Sensor Communication Circuit Performance

DTC P2135

Throttle Position Sensors 1-2 Not Plausible

Diagnostic Fault Information

Typical Scan Tool Data

Throttle Position Sensor 1

Throttle Position Sensor 2

Circuit/System Description

The throttle body assembly contains a contact-less inductive throttle position sensing element that is managed by a customized integrated circuit. The throttle position sensor is mounted within the throttle body assembly and is not serviceable. The engine control module (ECM) supplies the throttle body with a 5 V reference circuit, a low reference circuit, an H-bridge motor directional control circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the throttle body to the ECM. The throttle body cannot receive data from the ECM over the signal/serial data circuit. The throttle position sensor provides a signal voltage that changes relative to throttle blade angle. The customized integrated circuit translates the voltage based position information into serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The throttle position sensor information is transmitted between the throttle body and the ECM on the signal/serial data circuit. The ECM decodes the serial data into a representation of voltage signals that are occurring in the throttle body. The information is then displayed on a scan tool as the voltage inputs from TP sensors 1 and 2.

Conditions for Running the DTC

P0121

• DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0117, P0118, P0335, or P0336 is not set.
• The engine speed is between 500 - 6, 800 RPM.
• The engine coolant temperature (ECT) is -7 to +125ºC (19 - 257ºF).
• The intake air temperature (IAT) is -20 to +126ºC (-4 to +259ºF).
• The DTC runs continuously when the above conditions are met.

P0122, P0123, P0222, P0223

• DTC P06A3 is not set.
• The ignition is ON or the engine is running.
• The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
• The DTCs run continuously when the above condition are met.

P16A0, P16A1, or P16A2

• DTC P06A3 is not set.
• The ignition is ON or the engine is operating.
• The run/crank voltage is greater than 6.41 V.
• The DTCs run continuously once the above conditions are met for greater than 1 s.

P2135

• DTCs P0122, P0123, P0222, P0223, or P06A3 are not set.
• The ignition is ON or the engine is running.
• The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

P0121

The ECM detects that the throttle position sensor 1 voltage is stuck within normal operating range for greater than 1 s.

P0122

The ECM detects the throttle position sensor 1 signal voltage is less than 0.33 V for greater than 1 s.

P0123

The ECM detects the throttle position sensor 1 signal voltage is greater than 4.75 V for greater than 1 s.

P0222

The ECM detects the throttle position sensor 2 signal voltage is less than 0.25 V for greater than 1 s.

P0223

The ECM detects the throttle position sensor 2 signal voltage is greater than 4.59 V for greater than 1 s.

P16A0

The ECM detects a low voltage circuit condition on the throttle position sensor signal circuit for greater than 1 s.

P16A1

The ECM detects a high voltage circuit condition on the throttle position sensor signal circuit for greater than 1 s.

P16A2

The ECM detects an incorrect message was received over the throttle position sensor signal circuit for greater than 1 s.

P2135

• The ECM detects that throttle position sensors 1 and 2 disagree greater than 7 - 10 percent for greater than 1 s.

OR

• The ECM detects that the TP sensor 1 and 2 learned minimum throttle position is greater than 5 percent of the 5 volt reference voltage.

Action Taken When the DTC Sets

• DTCs P0121 is a Type B DTC.
• DTCs P0122, P0123, P0222, P0223, P16A0, P16A1, P16A2, and P2135 are Type A DTCs.
• The ECM commands the throttle actuator control (TAC) system to operate in a Reduced Engine Power mode.
• A message center or an indicator displays Reduced Engine Power.
• Under certain conditions, the ECM commands the engine OFF.

Conditions for Clearing the DTC

• DTCs P0121 is a Type B DTC.
• DTCs P0122, P0123, P0222, P0223, P16A0, P16A1, P16A2, and P2135 are Type A DTCs.

Diagnostic Aids

• A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
• If the accelerator pedal is pressed to the wide open throttle position, the throttle blade angle or Throttle Position angle is limited to less than 40 percent.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON,

2. Verify that DTC P0601 - P0606, P06A3, and P16F3 is not set.

• If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If a DTC is not set

3. Verify the scan tool Throttle Body Idle Air flow Compensation parameter is less than 90 %.

• If 90 % or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90 %

4. Verify that DTC P0122, P0123, P0222, P0223, P16A0, P16A1, P16A2, or P2135 are not set.

• If DTC P0122, P0123, P0222, P0223, or P2135 are the only DTCs set

Replace the Q38 Throttle Body.

• If DTC P16A0, P16A1, or P16A2 is set with any of the DTCs

Refer to Circuit/System Testing

• Go to next step: If none of the DTCs are set

5. Verify the Throttle Position Sensors 1 and 2 parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Agree is not displayed

Test or replace the Q38 Throttle Body Assembly.

• Go to next step: If Agree is displayed

6. Verify DTC P0122, P0123, P0222, P0223, P16A0, P16A1, P16A2, and P2135 is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If a DTC is not set

7. Determine the current vehicle testing altitude.

8. Verify the scan tool MAP Sensor pressure parameter is within range specified in the Altitude Versus Barometric Pressure table.

• If the MAP Sensor pressure is not in range

Refer to DTC P0106.

• Go to next step: If the MAP Sensor pressure is within range

9. Engine idling.

10. Verify the scan tool MAP Sensor pressure parameter is between 26 - 52 kPa (3.8 - 7.5 psi) and changes with accelerator pedal input.

• If not between 26 - 52 kPa (3.8 - 7.5 psi) or does not change

Refer to DTC P0106.

• Go to next step: If between 26 - 52 kPa (3.8 - 7.5 psi) and changes

11. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3, 000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• If the MAF Sensor parameter does not change smoothly and gradually

Refer to DTC P0101.

• Go to next step: If the MAF Sensor parameter changes smoothly and gradually

12. Verify the scan tool Boost Pressure Sensor pressure and BARO parameters are within 3 kPa (0.4 psi) with engine at idle.

• If the parameters are not within 3 kPa (0.4 psi)

Refer to DTC P0236.

• Go to next step: If the parameters are within 3 kPa (0.4 psi)

13. Verify the scan tool MAP Sensor parameter and the Boost Pressure Sensor parameter are within 20 kPa (2.9 psi) during a WOT acceleration at the time of the 1 - 2 shift.

• If the parameters are not within 20 kPa (2.9 psi)

Refer to DTC P0236

• Go to next step: If the parameters are within 20 kPa (2.9 psi)

14. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

15. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

16. All OK.

Circuit/System Testing

NOTE: Disconnecting the throttle body harness connector causes additional DTCs to set.

1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at Q38 Throttle Body Assembly. It may take up to 2 min for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 4 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 5 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Ignition ON.

6. Test for 4.8 - 5.2 V between the signal circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

7. Test or replace the Q38 Throttle Body Assembly.

Repair Instructions

• Throttle Body Assembly Replacement
• Control Module References for engine control module replacement, programming, and setup

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.

5. Ignition ON.

6. Verify the Throttle Position Sensors 1 and 2 parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Agree is not displayed

Test or replace the Q38 Throttle Body Assembly.

• Go to next step: If Agree is displayed

7. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not set.

• If DTC sets

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If DTC does not set

8. All OK.

DTC P0128

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0128

Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature

Diagnostic Fault Information

Typical Scan Tool Data

ECT Sensor

Circuit/System Description

The purpose of this diagnostic is to analyze the performance of the thermostat by using the engine coolant temperature (ECT) sensor to determine if the engine coolant will increase at the correct rate, and also to meet the calibrated target temperatures under various operating conditions.

The ECM uses the start-up ECT and the start-up intake air temperature (IAT) to begin the diagnostic calculation. The air flow into the engine is accumulated, and vehicle speed, distance, and engine run time are also factored in to determine if the ECT does increase normally and reach the calibrated target temperatures.

Conditions for Running the DTC

• DTCs P00B3, P00B6, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117 or P0118 are not set.
• The engine OFF time is greater than 30 m.
• The start-up ECT sensor is between -40º to 66ºC (- 40º to 151ºF).
• Engine run time between 30 s and 30 m.
• The Ethanol in the fuel is less than 87 %.
• The vehicle has traveled greater than 0.8 kilometers (0.5 miles).
• The DTC runs once per ignition cycle when the above conditions are met.

Conditions for Setting the DTC

• The ECM determines that the ECT has not met its calibrated target of 71º C (160 ºF) when the start-up ambient temperature was between 10 and 52º C (50 and 126º F), for greater than 1 s.

  OR

• The ECM determines that the ECT has not met its calibrated target of 55º C (131 ºF) when the start-up ambient temperature was between - 7 and 10º C (19 and 50º F), for greater than 1 s.

Action Taken When the DTC Sets

• DTC P0128 is a Type B DTC.
• The cooling fans will be commanded ON.
• The AC compressor will be commanded OFF.

Conditions for Clearing the MIL/DTC

DTC P0128 is a Type B DTC.

Diagnostic Aids

• DTC P0128 occurring with insufficient vehicle interior heating is an indication of improper thermostat operation.
• A slight to moderate resistance in the ECT sensor signal circuit or low reference circuit will affect this diagnostic. This condition results in a greater voltage on the ECT sensor signal circuit, which is interpreted by the ECM as a colder ECT.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Cooling System Description and Operation

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, verify that DTC P00B3, P00B6, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117 or P0118 is not set.

• If DTC P00B3, P00B6, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117 or P0118 is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle

• Go to next step: If DTC P00B3, P00B6, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117 or P0118 is not set

2. Verify the cooling system is filled to the correct coolant level. Refer to Cooling System Draining and Filling (Static) or Cooling System Draining and Filling (GE 47716). If necessary, refer to Loss of Coolant.

• If the coolant level is not correct

Repair as necessary

• Go to next step: If the coolant level is correct

3. Engine running for 15 min with the A/C OFF, increase the engine speed to 3, 000 RPM.

4. Verify the scan tool ECT Sensor parameter is greater than 80ºC (176ºF).

• If less than 80ºC (176ºF)

Replace the Engine Coolant Thermostat.

• Go to next step: If greater than 80ºC (176ºF)

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the B34 Engine Coolant Temperature sensor harness connector at the sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal A or 2 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Verify the scan tool ECT Sensor parameter is colder than -39º C (-38º F).

• If warmer than -39º C (-38º F)

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal B or 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If colder than -39º C (-38º F)

5. Install a 3 A fused jumper wire between the signal circuit terminal B or 1 and the low reference circuit terminal A or 2.

6. Verify the scan tool ECT sensor parameter is warmer than 149º C (300º F).

• If 149º C (300º F) or colder

1. Ignition OFF, remove the jumper wire, disconnect the X2 harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
3. Ignition OFF.
4. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 149º C (300º F)

7. Test the B34 Engine Coolant Temperature Sensor.

Refer to Component Testing.

Component Testing

1. Ignition OFF, disconnect the harness connector at the B34 Engine Coolant Temperature Sensor.

2. Test the ECT sensor by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Engine Coolant Temperature Sensor table. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B34 Engine Coolant Temperature Sensor.

• Go to next step: If within the specified range

3. Test for infinite resistance between each terminal and the sensor housing.

• If less than infinite resistance

Replace the B34 Engine Coolant Temperature Sensor.

• Go to next step: If infinite resistance

4. Refer to Thermostat Diagnosis.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Engine Coolant Temperature Sensor Replacement
• Engine Coolant Thermostat Housing Replacement (2.0L LTG) or Engine Coolant Thermostat Housing Replacement (3.6L LGX)
• Control Module References for ECM replacement, setup and programming

DTC P0131, P0132, P015A, P015B, P223C, or P223E

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptors

DTC P0131

HO2S Circuit Low Voltage Sensor 1

DTC P0132

HO2S Circuit High Voltage Sensor 1

DTC P015A

HO2S Delayed Response Rich to Lean Sensor 1

DTC P015B

HO2S Delayed Response Lean to Rich Sensor 1

DTC P223C

HO2S Pump Current Control Performance Bank 1 Sensor 1

DTC P223E

HO2S Reference Resistance Out of Range Bank 1 Sensor 1

Diagnostic Fault Information

Typical Scan Tool Data

HO2S 1

Circuit/System Description

The wide band heated oxygen sensor (HO2S) measures the amount of oxygen in the exhaust system and provides more information than the switching style HO2S. The wide band sensor consists of an oxygen sensing cell, an oxygen pumping cell, and a heater. The exhaust gas sample passes through a diffusion gap between the sensing cell and the pumping cell. The engine control module (ECM) supplies a voltage to the HO2S and uses this voltage as a reference to the amount of oxygen in the exhaust system. An electronic circuit within the ECM controls the pump current through the oxygen pumping cell in order to maintain a constant voltage in the oxygen sensing cell. The ECM monitors the voltage variation in the sensing cell and attempts to keep the voltage constant by increasing or decreasing the amount of current flow, or oxygen ion flow, to the pumping cell. By measuring the amount of current required to maintain the voltage in the sensing cell, the ECM can determine the concentration of oxygen in the exhaust. The HO2S voltage is displayed as a lambda value. A lambda value of 1 is equal to a stoichiometric air fuel ratio of 14.7: 1. Under normal operating conditions, the lambda value will remain around 1. When the fuel system is lean, the oxygen level will be high and the lambda signal will be high or more than 1.

When the fuel system is rich, the oxygen level will be low, and the lambda signal will be low or less than 1. The ECM uses this information to maintain the correct air/fuel ratio. If the ECM detects that the HO2S signal voltage is low, this DTC sets.

The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed Loop earlier and the control module to calculate the air-to-fuel ratio sooner.

Conditions for Running the DTC

P0131, P0132

• DTC P0030, P0031, P0032, P0135 = Not set
• Ignition Voltage=10 to 32 V
• Engine Running
• DTCs run continuously when the above conditions are met for greater than 4 s.

P015A, P015B

• DTC P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0131, P013A, P013B, P013E, P013F, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176, P2270, P2271 = Not set
• P015A has run and passed for P015B to run.
• Ignition Voltage=10 to 32 V
• Engine Coolant Temperature=Warmer than 62ºC (144ºF)
• Intake Air Temperature=Warmer than -40ºC (-40ºF)
• Fuel Level Sensor=Greater than 10%
• Engine Run Time=Greater than 120 s
• Engine Speed=950 to 2950 RPM
• Vehicle Speed=66 to 124 km/h (41 to 77 MPH)
• Mass Air Flow=2 to 15 g/s
• Barometric Pressure=Greater than 70 kPa (10 PSI)
• Fuel Control Loop Status=Closed Loop Fuel Control
• Device controls are not active.
• The evaporative emission (EVAP) diagnostics are not in control of purge.
• HO2S 1 Heater Command=On for greater than 20 s
• After the above conditions are met for 2 s the fuel mixture is forced rich.
• At the end of the forced rich fuel state, decel fuel cut-off is active, without driver initiated accelerator pedal input.
• DTCs run once per drive cycle when the above conditions are met.

P223C

• DTC P0030, P0031, P0032, P0135 = Not set
• Ignition Voltage=10 to 32 V
• Engine Running
• The DTC runs when time in decel fuel cut-off is greater than 5 s and less than 12 s, when the above conditions are met for 7 s.

P223E

• DTC P0030, P0031, P0032, P0135 = Not set
• Ignition Voltage=10 to 32 V
• Engine Running
• DTC runs continuously when the above conditions are met for greater than 30 s.

Conditions for Setting the DTC

P0131

The engine control module detects that the heated oxygen sensor pump current or reference voltage circuit is shorted to ground for greater than 4 s.

P0132

The engine control module detects that the heated oxygen sensor pump current, reference voltage, or reference ground circuit is shorted to voltage for greater than 4 s.

P015A or P015B

The engine control module detects that the heated oxygen sensor rich-to-lean or lean-to-rich average response time is greater than a calibrated value.

The DTCs set within 60 s when the above condition is met.

P223C

The engine control module detects an open circuit fault to the pump current, reference voltage, reference ground, or trim circuit or a trim circuit short to ground, by detecting that the pump current is less than 0.10 mA or greater than 4.18 mA for greater than 7 s.

P223E

The engine control module detects that the heated oxygen sensor reference cell is colder than 700ºC (1292ºF) or warmer than 1000ºC (1832ºF) for greater than 4 s.

Actions Taken When the DTC Sets

• DTCs P0131, P0132, P223C, P223E are Type B DTCs.
• DTCs P015A, P015B are Type A DTCs.

Conditions for Clearing the DTC

• DTCs P0131, P0132, P223C, P223E are Type B DTCs.
• DTCs P015A, P015B are Type A DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode

2. Verify no other DTCs are set.

• If other DTCs are set

Refer to: Diagnostic Trouble Code (DTC) List - Vehicle

• Go to next step: If no other DTCs are set

3. Engine running.

4. Verify the scan tool parameter: HO2S 1=Between Lambda 0.8 and 1.1

• If not between Lambda 0.8 and 1.1

Refer to: Circuit/System Testing

• Go to next step: If between Lambda 0.8 and 1.1

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set

6. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the electrical connector: B52 Heated Oxygen Sensor.

3. Test for less than 10 ohms between the test points: Low Reference circuit terminal 1 & Ground.

• If 10 ohms or greater

1. Disconnect the electrical connector: K20 Engine Control Module
2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 1@Component harness & Terminal X3 38@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Test or replace the component: K20 Engine Control Module

• Go to next step: If less than 10 ohms

4. Disconnect the electrical connector: K20 Engine Control Module.

5. Test for infinite resistance between the test points: Signal circuit terminal 2@Component harness & Ground

• If less than infinite resistance

Repair the short to ground on the circuit:

• Go to next step: If infinite resistance

6. Ignition - On / Vehicle - In Service Mode.

7. Test for less than 1 V between the test points: Signal circuit terminal 2@Component harness & Ground.

• If 1 V or greater

Repair the short to voltage on the circuit:

• Go to next step: If less than 1 V

8. Ignition/Vehicle - Off.

9. Test for less than 2 ohms between the test points: Signal circuit terminal 2@Component harness & Terminal X3 36@Control module harness.

• If 2 ohms or greater - Repair the open/high resistance in the circuit.
• Go to next step: If less than 2 ohms

10. Test for infinite resistance between the test points: Signal circuit terminal 3@Component harness & Ground

• If less than infinite resistance

Repair the short to ground on the circuit:

• Go to next step: If infinite resistance

11. Ignition - On / Vehicle - In Service Mode.

12. Test for less than 1 V between the test points: Signal circuit terminal 3@Component harness & Ground

• If 1 V or greater

Repair the short to voltage on the circuit:

• Go to next step: If less than 1 V

13. Ignition/Vehicle - Off.

14. Test for less than 2 ohms between the test points: Signal circuit terminal 3@Component harness & Terminal X3 37@Control module harness.

• If 2 ohms or greater - Repair the open/high resistance in the circuit.
• Go to next step: If less than 2 ohms

15. Test for infinite resistance between the test points: Signal circuit terminal 7@Component harness & Ground

• If less than infinite resistance

Repair the short to ground on the circuit:

• Go to next step: If infinite resistance

16. Ignition - On / Vehicle - In Service Mode.

17. Test for less than 1 V between the test points: Signal circuit terminal 7@Component harness & Ground.

• If 1 V or greater

Repair the short to voltage on the circuit:

• Go to next step: If less than 1 V

18. Ignition/Vehicle - Off.

19. Test for less than 2 ohms between the test points: Signal circuit terminal 7@Component harness & Terminal X3 35@Control module harness.

• If 2 ohms or greater - Repair the open/high resistance in the circuit.
• Go to next step: If less than 2 ohms

20. Verify none of the conditions listed below exist:

• Water intrusion in the following components or their wiring harnesses: B52 Heated Oxygen Sensor
• Fuel pressure low or high. Refer to: Fuel System Diagnosis
• Contaminated or poor quality fuel. Refer to: Alcohol/Contaminants-in-Fuel Diagnosis
• Fuel saturation of the evaporative emission (EVAP) canister
• Exhaust leaks
• Engine vacuum leaks.
• Oil consumption - Refer to: Oil Consumption Diagnosis
• Coolant consumption - Refer to: Loss of Coolant
• If a condition exists

Repair as necessary

• Go to next step: If no conditions exist

21. Test or replace the component: B52A Heated Oxygen Sensor 1.

22. Perform the scan tool configuration/reset function: HO2S Heater Resistance Reset.

23. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Test or replace the component: K20 Engine Control Module

• Go to next step: If the DTC is not set

24. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Heated Oxygen Sensor Replacement - Sensor 1
• Control Module References for ECM replacement, programming and setup

DTC P0137, P0138, P013A, P013B, P013E, P013F, P2270, or P2271

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0137

HO2S Circuit Low Voltage Sensor 2

DTC P0138

HO2S Circuit High Voltage Sensor 2

DTC P013A

HO2S Slow Response Rich to Lean Sensor 2

DTC P013B

HO2S Slow Response Lean to Rich Sensor 2

DTC P013E

HO2S Delayed Response Rich to Lean Sensor 2

DTC P013F

HO2S Delayed Response Lean to Rich Sensor 2

DTC P2270

HO2S Signal Stuck Lean Sensor 2

DTC P2271

HO2S Signal Stuck Rich Sensor 2

Diagnostic Fault Information

Typical Scan Tool Data

HO2S Sensor 2

Circuit/System Description

The heated oxygen sensors (HO2S) are used for fuel control and catalyst monitoring. Each HO2S 2 compares the oxygen content of the surrounding air with the oxygen content of the exhaust stream.

When the engine is started, the control module operates in an Open Loop mode, ignoring the HO2S signal voltage while calculating the air-to-fuel ratio. While the engine runs, the HO2S heats up and begins to generate a voltage within a range of 0 - 1, 000 mV. Once sufficient HO2S voltage fluctuation is observed by the control module, Closed Loop is entered. The control module uses the HO2S voltage to determine the air-to-fuel ratio. An HO2S voltage that increases toward 1, 000 mV indicates a rich fuel mixture. An HO2S voltage that decreases toward 0 mV indicates a lean fuel mixture.

The heating elements inside each HO2S heat the sensor to bring the sensor up to operating conditions faster. This allows the system to enter Closed Loop earlier and the control module to calculate the air-to-fuel ratio sooner.

Conditions for Running the DTC

P0137

• DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
• The Ignition voltage is between 10 - 32 V.
• The fuel system is operating in Closed Loop.
• Device controls are not active.
• The fuel level is greater than 10 %.
• Ethanol content is less than 87 %.
• Decel fuel cut-off is not active.
• The DTCs run continuously when the above conditions are met for 5 s.

P0138

• DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P0201, P0202, P0203, P0204, P0205, P0206, P0207, P0208, P0220, P0222, P0223, P0442, P0443, P0446, P0449, P0455, P0496, P1516, P2101, P2119, P2135, P2176 are not set.
• The Ignition voltage is between 10 - 32 V.
• Ignition is OFF for greater than 8 h.
• The fuel system is operating in Closed Loop.
• Ethanol content is less than 87 %.
• The fuel level is greater than 10 %.
• The engine run time is greater than 30 s.
• The engine is not in Power Enrichment.
• The DTCs run continuously after an initial delay of 3 min when the above conditions are met for 5 s.

P013A or P013E

• Before the ECM can report DTC P013A, or P013C failed, DTCs P013E, P014A, P2270, and P2272 must run and pass.
• Before the ECM can report DTC P013E, or P014A failed, DTCs P2270 and P2272 must run and pass.
• DTCs P0030, P0036, P0053, P0054, P0101, P0102, P0103, P0106, P0107, P0108, P0120, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P0171, P0172, P0201 - P0208, P0220, P0222, P0223, P0300 - P0308, P0442, P0443, P0446, P0449, P0455, P0496, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set.
• The Ignition voltage is between 10 - 32 V.
• The engine is OFF for greater 8 h.
• The learned heater resistance is valid.
• The fuel level is greater than 10%.
• After the above conditions are met decel fuel cut-off continues without driver initiated pedal input.
• The DTCs run once per ignition cycle, during decel fuel cut-off (DFCO), when the above conditions are met.

P013B or P013F

• Before the ECM can report DTC P013B, or P013D failed, DTCs P013A, P013C, P013E, P013F, P014A, P014B, P2270, P2271, P2272, and P2273 must run and pass.
• Before the ECM can report DTC P013F, or P014B failed, DTCs P013A, P013C, P013E, P014A, P2270, P2271, P2272, and P2273 must run and pass.
• DTCs P0030, P0036, P0053, P0054, P0101, P0102, P0103, P0106, P0107, P0108, P0120, P0121, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P0171, P0172, P0201 - P0208, P0220, P0222, P0223, P0300 - P0308, P0442, P0443, P0446, P0449, P0455, P0496, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set.
• The Ignition voltage is between 10 - 32 V.
• The engine is OFF for greater 8 h.
• The learned heater resistance is valid.
• The fuel level is greater than 10%.
• After the above conditions are met, fuel enrich mode is continued.
• The DTCs run once per ignition cycle when the above conditions are met.

P2270

• DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P013A, P013B, P013E, P013F, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0411, P0412, P0418, P1174, P1516, P2101, P2119, P2135, P2176, P2270, P2271 are not set.
• The system voltage is between 10 - 32 V.
• The engine is OFF for greater 8 h.
• The fuel level is greater than 10%.
• The pedal position is less than 4%.
• The engine speed is between 950 - 2, 950 RPM.
• The engine airflow is between 3 - 12 g/s.
• The vehicle speed is between 66 - 124 km/h (41 - 77 mph).
• The fuel state is in Closed Loop.
• The evaporative emission (EVAP) diagnostics are not in control of purge.
• The HO2S heaters are ON for more than 80 s.

  The predicted catalytic converter temperature is between 500 - 850ºC (932 - 1, 562ºF).

• This DTC runs once per trip when all of the above conditions have been met for 1 s.

P2271

• DTCs P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0120, P0121, P0122, P0123, P0128, P013A, P013B, P013E, P013F, P0171, P0172, P0201, P0202, P0203, P0204, P0220, P0222, P0223, P0300, P0411, P0412, P0418, P1174, P1516, P2101, P2119, P2135, P2176, P2270 are not set.
• The system voltage is between 10 - 32 V.
• The engine is OFF for greater 8 h.
• The fuel level is greater than 10%.
• The fueling state is in Closed Loop.
• DTCs P013A, P013E, and P2270 have run and passed.
• Decel fuel cut-off is active.
• The accelerator pedal position is stable.
• This DTC runs once per trip when the above conditions are met for 3 s.

Conditions for Setting the DTC

P0137

The engine control module detects that the heated oxygen sensor voltage is less than 50 mV and the circuit is shorted to ground for greater than 50 s.

P0138

The engine control module detects that the heated oxygen sensor voltage is greater than 1, 050 mV and the circuit is shorted to voltage for greater than 13 s.

P013A

The engine control module detects that the accumulated mass air flow monitored during rich-to-lean transitions between 450 - 150 mV is greater than 36 grams.

P013B

The engine control module detects that the accumulated mass air flow monitored during lean-to-rich transitions between 300 - 600 mV is greater than 88 grams.

P013E

The engine control module detects an initial delayed response to a change from rich to lean such that the heated oxygen sensor voltage has not decreased to 450 mV within a calibrated value of accumulated air flow.

P013F

The engine control module detects an initial delayed response to a change from lean to rich such that the heated oxygen sensor voltage has not increased above 350 mV within a calibrated value of accumulated air flow.

P2270

The engine control module does not detect a heated oxygen sensor voltage greater than 825 mV before accumulated mass air flow exceeds a calibrated value.

P2271

The engine control module does not detect an heated oxygen sensor voltage less than 100 mV before accumulated mass air flow exceeds a calibrated value.

Action Taken When the DTC Sets

• DTCs P0137, P0138, P013E, P013F, P2270, and P2271 are Type B DTCs.
• DTCs P013A and P013B are Type A DTCs.

Conditions for Clearing the MIL/DTC

• DTCs P0137, P0138, P013E, P013F, P2270, and P2271 are Type B DTCs.
• DTCs P013A and P013B are Type A DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify no HO2S heater DTCs are set.

• If a DTC is set.

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If a DTC is not set.

3. Engine running.

4. Verify the scan tool HO2S 1 or 2 parameters are between 50 - 1, 050 mV.

• If not between 50 - 1, 050 mV.

Refer to Circuit/System Testing.

• Go to next step: If between 50 - 1, 050 mV.

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets.

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set.

7. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the appropriate B52 Heated Oxygen Sensor harness connector. It may take up to 2 minutes for all vehicle systems to power down. Ignition ON.

2. Test for 1.7 - 3.0 V between the high signal circuit terminal 4 and ground.

• If less than 1.7 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the high signal circuit terminal 4 and ground.
   • If less than infinite resistance repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the high signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 3.0 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the high signal circuit terminal 4 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 1.7 - 3.0 V

3. Verify the scan tool HO2S 2 parameter is between 1.7 - 2.1 V.

• If less than 1.7 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the low signal circuit terminal 3 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If between 1.7 - 2.1 V

4. Connect a 3 A fused jumper wire between the high signal circuit terminal 4 and the low signal circuit terminal 3.

NOTE: The low signal circuit is tied to a pull-up circuit within the engine control module. A voltage of 0.0 - 1.10 V on the low signal circuit is normal.

5. Verify the scan tool HO2S 1 or 2 parameter displays 0.0 V.

• If greater than 0.0 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 2 Ω in the low signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω
3. Test for less than 1 V between the low signal circuit terminal 3 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If 0.0 V

6. Verify none of the conditions listed below exist:

• Water intrusion in the B52 Heated Oxygen Sensor harness connector
• Low or high fuel system pressure - Refer to Fuel System Diagnosis.
• Fuel that is contaminated - Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Fuel saturation of the evaporative emission (EVAP) canister
• Exhaust leaks
• Engine vacuum leaks
• Engine oil consumption - Refer to Oil Consumption Diagnosis.
• Engine coolant consumption - Refer to Loss of Coolant.
• If any of the conditions exist

Repair as necessary.

• Go to next step: If none of the conditions exist

Go to next step: Test or replace the B52 Heated Oxygen Sensor

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Heated Oxygen Sensor Replacement - Sensor 1
• Heated Oxygen Sensor Replacement - Sensor 2
• Perform the scan tool Heated Oxygen Sensor Resistance Learn Reset after replacing an HO2S.
• Control Module References for ECM replacement, programming and setup

DTC P0171 or P0172

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0171

Fuel Trim System Lean

DTC P0172

Fuel Trim System Rich

Circuit/System Description

The engine control module (ECM) controls a Closed Loop air/fuel metering system in order to provide the best possible combination of driveability, fuel economy, and emission control. The ECM monitors the heated oxygen sensor (HO2S) signal voltage, and adjusts the fuel delivery based on the signal voltage while in Closed Loop. A change made to the fuel delivery changes the long and short term fuel trim values. The short term fuel trim values change rapidly in response to the HO2S signal voltages.

These changes fine tune the engine fueling. The long term fuel trim values change in response to trends in the short term fuel trim The long term fuel trim makes coarse adjustments to fueling in order to recenter and restore control to short term fuel trim. The ideal fuel trim values are around 0 %. A positive fuel trim value indicates that the ECM is adding fuel in order to compensate for a lean condition. A negative fuel trim value indicates that the ECM is reducing the amount of fuel in order to compensate for a rich condition.

Conditions for Running the DTC

• DTCs P0030, P0053, P0101, P0102, P0103, P0106, P0107, P0108, P0131 - P0135, P015A, P015B, P0178, P0179, P0201 - P0204, P0236, P0237, P0238, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300 - P0304, P0411, P0442, P0455, P0458, P0496, P0506, P0507, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157, P2227, P2228, P2229, P2230, P2269, P2440, P2444, or P2A00 are not set.
• The engine is in Closed Loop status.
• The catalyst monitor diagnostic intrusive test, post 02 diagnostic intrusive test, device control, and evaporative emission leak test are not active.
• The engine coolant temperature (ECT) is between -20 and +130ºC (-4 and +266ºF).
• The intake air temperature (IAT) is between -20 and +150ºC (-4 and +302ºF).
• The manifold absolute pressure (MAP) is between 15 - 255 kPa (2.2 - 37 psi).
• The engine speed is between 400 - 6, 600 RPM.
• The mass air flow (MAF) is between 1 - 512 g/s.
• The barometric pressure (BARO) is greater than 70 kPa (10.2 psi).
• The fuel level is greater than 10 %.
• This diagnostic runs continuously when the above conditions have been met.

Conditions for Setting the DTC

• The average long term fuel trim weighted average value is greater or less than a calibrated value.
• The above condition is present for approximately 3 min after the Conditions for Running the DTC have been met.

Action Taken When the DTC Sets

DTCs P0171 and P0172 are Type B DTCs.

Conditions for Clearing the MIL/DTC

TCs P0171 and P0172 are Type B DTCs.

Diagnostic Aids

• The normal Short Term Fuel Trim and Long Term Fuel Trim parameters should be between +10 and -10 % with 0 % the optimum, with the engine running at operating temperature.
• Any un-metered air into the engine causes this DTC to set. Thoroughly inspect all areas of the engine for vacuum leaks.
• A MAF sensor condition can cause this DTC without setting a MAF DTC. If there is a MAF sensor condition, the MAF sensor parameters will appear to be within range.
• Verify that the air filter is the correct one for this application. Verify that the engine oil fill cap is in place and that it is tight. Verify that the engine oil dip stick is fully seated.
• Certain aftermarket air filters may cause a DTC to set.
• Certain aftermarket air induction systems or modifications to the air induction system may cause a DTC to set.
• Certain aftermarket exhaust system components may cause a DTC to set.

Reference Information

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify no other DTCs are set.

• If any other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If no other DTCs are set

3. Verify DTC P0171 or P0172 is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If no DTC is set

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

5. Verify DTC P0171 or P0172 is not set.

• If any of the DTCs set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs set

6. All OK.

Circuit/System Testing

1. Ignition ON.

2. Verify the manifold absolute pressure sensor is within the range specified for your altitude. Refer to Altitude Versus Barometric Pressure.

• If not within the specified range

Refer to DTC P0106

• Go to next step: If within the specified range

3. Engine running at the operating temperature.

4. Verify the Long Term Fuel Trim parameter is between -10 % and +10 %.

If greater than +10 %

1. Ignition OFF.
2. Inspect for the conditions listed below:
   • Mass air flow (MAF) sensor signal skewed. If the Short Term Fuel Trim parameter changes greater than 20 % when the MAF sensor is disconnected, refer to DTC P0101.
   • Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
   • Missing, restricted, or leaking exhaust components. Refer to Symptoms - Engine Exhaust.
   • Malfunctioning fuel injectors. Refer to Fuel Injector Diagnosis.
   • Split, kinked or improperly connected vacuum hoses.
   • Insufficient fuel in the tank
   • Low fuel pressure. Refer to Fuel System Diagnosis.
   • Vacuum leaks at the intake manifold, the throttle body, and the injector O-rings.
   • Leaks in the air induction system and the air intake ducts
   • Missing air filter element
   • Cracked EVAP canister
   • Evaporative pipes obstructed or leaking
   • Leaks in the crankcase ventilation system. Refer to Crankcase Ventilation System Inspection/Diagnosis.
     • If a condition is found, repair as necessary.
     • If no condition is found, inspect the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical.

• If less than -10 %

1. Ignition OFF.
2. Inspect for the conditions listed below:
   • Mass air flow (MAF) sensor signal skewed. If the Short Term Fuel Trim parameters for both banks changes greater than 20 % when the MAF sensor is disconnected, refer to DTC P0101.
   • Fuel contamination - Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
   • Missing, restricted, or leaking exhaust components - Refer to Symptoms - Engine Exhaust.
   • Malfunctioning fuel injectors - Refer to Fuel Injector Diagnosis
   • Collapsed or restricted air intake duct
   • Excessive fuel pressure - Refer to Fuel System Diagnosis
   • Dirty or restricted air filter
   • Objects blocking the throttle body
   • Improper operation of the evaporative emissions control system
   • Excessive fuel in the crankcase - Change engine oil as necessary and inspect for the following:

G18 High Pressure Fuel Pump=Leaking

Q17 Fuel Injector=Leaking - Refer to Fuel Injector Diagnosis

• If a condition is found, repair as necessary.
• If no condition is found, inspect the engine for a mechanical condition. Refer to Symptoms - Engine Mechanical.
• Go to next step: If between -10 % and +10 %

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

6. Verify DTC P0171 or P0172 is not set.

• If any of the DTCs set

Refer to conditions listed above.

• Go to next step: If none of the DTCs set

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Perform the scan tool Fuel Trim Reset after completing the repair.

DTC P018B-P018D

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P018B

Fuel Pressure Sensor Performance

DTC P018C

Fuel Pressure Sensor Circuit Low Voltage

DTC P018D

Fuel Pressure Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The fuel pressure sensor is located on the fuel pipe. The fuel pressure sensor monitors the fuel pressure in the fuel line. The engine control module (ECM) monitors the voltage signal from the fuel pressure sensor. The sensor provides a fuel pressure signal to the ECM, which is used to provide Closed Loop fuel pressure control.

Conditions for Running the DTC

P018B

• DTC P018C, P018D, P0231, P0232, P023F, P0606, P0641, or P1255 is not set.
• The engine is running for greater than 5 s.
• The fuel pump enable circuit is commanded ON.
• Low fuel level warning not present.
• The DTC runs continuously when the conditions above are met.

P018C or P018D

• The engine is cranking or running.
• The DTCs run continuously when the condition above is met.

Conditions for Setting the DTC

P018B

The engine control module does not detect a normal fuel pressure change when the fuel pump is operating. The fuel pressure sensor performance diagnostic provides a means to detect fuel pressure sensor output that is stuck within the normal operating range of the sensor.

P018C

The engine control module detects that the fuel pressure sensor voltage is less than 0.2 V for 1 s.

P018D

The engine control module detects that the fuel pressure sensor voltage is greater than 4.8 V for 1 s.

Action Taken When the DTC Sets

DTC P018B, P018C and P018D are Type A DTCs.

Conditions for Clearing the DTC

DTC P018B, P018C and P018D are Type A DTCs.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Testing for Intermittent Conditions and Poor Connections
• Connector Repairs
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC U0074 or U18A2 is not set or stored in history.

• If DTC U0074 or U18A2 is set or stored in history

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If DTC U0074 or U18A2 is not set or stored in history

3. Engine running.

4. Verify the scan tool Fuel Pressure Sensor parameter is between 0.2 - 4.8 V.

• If not between 0.2 - 4.8 V

Refer to Circuit/System Testing.

• Go to next step: If between 0.2 - 4.8 V

5. Verify the scan tool Fuel Pressure Sensor increases or decreases when commanding an increase and decrease in Fuel Pressure with a scan tool.

• If the parameter does not change

Refer to Circuit/System Testing.

• Go to next step: If the parameter changes

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B47 Fuel Pressure Sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool Fuel Pressure Sensor parameter is less than 1 V.

• If 1 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal 1 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 1 V

6. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the 5 V reference circuit terminal 3, wait 15 seconds.

7. Verify the scan tool Fuel Pressure Sensor parameter is greater than 4.8 V.

• If 4.8 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.8 V

8. Replace the B47 Fuel Pressure Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Pressure Sensor Replacement - Fuel Feed Pipe (AWD) or Fuel Pressure Sensor
• Replacement - Fuel Feed Pipe (FWD)
• Control Module References for control module replacement, programming and setup.

DTC P0191 or P0192

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0191

Fuel Rail Pressure Sensor Performance

DTC P0192

Fuel Rail Pressure Sensor Circuit Low Voltage

Diagnostic Fault Information

Circuit/System Description

The fuel rail pressure sensor transmits fuel pressure and temperature information by serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The fuel rail pressure sensor internal microprocessor allows 4 separate sensor outputs from one 3 wire sensor. The engine control module (ECM) supplies the fuel rail pressure sensor with a 5 V reference circuit, a low reference circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the fuel rail pressure sensor to the ECM.

Conditions for Running the DTC

P0191 - Condition 1

• The engine is not cranking.
• The ignition voltage is greater than 11 V.
• The vehicle speed is less than or equal to 1 km/h (0.62 MPH).
• The low side fuel pressure is greater than or equal to 250 kPa (36 PSI).
• The Accelerator Pedal Position is 0% for 2.5 s.
• The engine is running for greater than 30 s.

P0191 - Condition 2 and 3

• The engine is not cranking.
• The ignition voltage is greater than 11 V.
• The engine speed is between 1, 000 - 3, 000 RPM.
• The vehicle speed is greater than or equal to 35 km/h (22 MPH).
• The low side fuel pressure is greater than or equal to 250 kPa (36 PSI).
• The Desired Fuel Rail Pressure is between 4 - 6 MPa (580 - 870 PSI).
• The Accelerator Pedal Position is greater than or equal to 10%.
• The engine is running for greater than 30 s.

P0191 - Condition 4

• DTC P0016, P0017, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0122, P0123, P0128, P0192, P0193, P0201, P0202, P0203, P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0340, P0341, P0351 - P0354, P0365, P0366, P0506, P0507, P0628, P0697, P06A3, P0722, P0723, P1248, P1249, P124A, P124B, P1682, P2122, P2123, P2127, P2128, P2135, P2138, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157 is not set.
• The engine is not cranking.
• The vehicle speed is greater than or equal to 30 km/h (18.64 MPH).
• The engine speed is greater than or equal to 2, 000 RPM.
• The barometric (BARO) pressure is greater than 70 kPa.
• The intake air temperature (IAT) is warmer than -20ºC (-4ºF).

P0192

• The engine is running.
• The ignition voltage is greater than 11 V.
• The DTCs run continuously within the enabling conditions.

Conditions for Setting the DTC

P0191 - Condition 1

The difference between the low side fuel pressure and the high side fuel pressure is less than or equal to -1 MPa (-145 PSI) or greater than or equal to 1 MPa (145 PSI) with the high pressure fuel pump actuator commanded OFF. The condition exists for greater than 3 s.

P0191 - Condition 2

The difference between the relief pressure and the measured high pressure is less than or equal to -1.6 MPa (-232 PSI) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 2 s.

P0191 - Condition 3

The difference between the commanded high pressure and the measured high pressure is greater than or equal to 3 MPa (435 PSI) and the modeled injection pressure is greater than or equal to 1.6 MPa (232 PSI) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 3 s.

P0191 - Condition 4

The difference between the measured maximum high pressure and the measured minimum high pressure is less than or equal to 0.1 MPa (14.5 PSI) with the high pressure fuel pump actuator commanded ON.

The condition exists for greater than 30 s with the engine running or greater than 10 s with the engine cranking.

P0192

The ECM detects that the fuel rail fuel pressure sensor signal voltage is low for greater than 5 s.

Action Taken When the DTC Sets

• DTCs P0191, P0192, are Type A DTCs.
• A message center or an indicator may display Reduced Engine Power.

Conditions for Clearing the DTC

• DTCs P0191, P0192 are Type A DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition On.

2. Verify DTC P0641 is not set.

• If the DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If the DTC is not set

3. Engine idling.

4. Verify DTC P0191 or P0192 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset.

You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the fuel injector multi-way harness connector X160. It may take up to 2 mins for all vehicle systems to power down.

NOTE: Testing for steps 2 through 7 is performed on the ECM side of the multi-way harness connector.

2. Test for less than 5 Ω between the low reference circuit terminal 5 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition On.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 11 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.

• If 0.02 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the signal circuit terminal 12 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.02 V

6. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the 5 V reference circuit terminal 11.

7. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.96 V.

• If 4.96 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 12 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.96 V

8. Connect the fuel injector multi-way harness connector X160.

9. Disconnect the B47B Fuel Rail Pressure Sensor connector.

NOTE: Testing for steps 11 through 17 is performed at the fuel rail fuel pressure sensor connector.

10. Test for less than 5 Ω between the low reference circuit terminal 1 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

11. Ignition On.

12. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

13. Ignition On.

14. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.

• If 0.02 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the signal circuit terminal 2 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.02 V

15. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the 5 V reference circuit terminal 3.

16. Verify the scan tool Fuel Rail Pressure Sensor voltage parameter is greater than 4.96 V.

• If 4.96 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.96 V

17. Replace the B47B Fuel Rail Pressure Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement
• Control Module References for ECM replacement, setup, and programming

DTC P0201-P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, or P2157

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0201

Cylinder 1 Injector Control Circuit

DTC P0202

Cylinder 2 Injector Control Circuit

DTC P0203

Cylinder 3 Injector Control Circuit

DTC P0204

Cylinder 4 Injector Control Circuit

DTC P0261

Cylinder 1 Injector Control Circuit Low Voltage

DTC P0262

Cylinder 1 Injector Control Circuit High Voltage

DTC P0264

Cylinder 2 Injector Control Circuit Low Voltage

DTC P0265

Cylinder 2 Injector Control Circuit High Voltage

DTC P0267

Cylinder 3 Injector Control Circuit Low Voltage

DTC P0268

Cylinder 3 Injector Control Circuit High Voltage

DTC P0270

Cylinder 4 Injector Control Circuit Low Voltage

DTC P0271

Cylinder 4 Injector Control Circuit High Voltage

DTC P1248

Cylinder 1 Injector High Control Circuit Shorted to Control Circuit

DTC P1249

Cylinder 2 Injector High Control Circuit Shorted to Control Circuit

DTC P124A

Cylinder 3 Injector High Control Circuit Shorted to Control Circuit

DTC P124B

Cylinder 4 Injector High Control Circuit Shorted to Control Circuit

DTC P2147

Cylinder 1 Injector High Control Circuit Low Voltage

DTC P2148

Cylinder 1 Injector High Control Circuit High Voltage

DTC P2150

Cylinder 2 Injector High Control Circuit Low Voltage

DTC P2151

Cylinder 2 Injector High Control Circuit High Voltage

DTC P2153

Cylinder 3 Injector High Control Circuit Low Voltage

DTC P2154

Cylinder 3 Injector High Control Circuit High Voltage

DTC P2156

Cylinder 4 Injector High Control Circuit Low Voltage

DTC P2157

Cylinder 4 Injector High Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) supplies voltage to each fuel injector on the high control circuits. The ECM energizes each fuel injector by grounding the low control circuit of the fuel injector. The ECM monitors the status of the fuel injector circuits. When a fuel injector circuit condition is detected by the ECM, the affected fuel injector (s) is disabled.

Conditions for Running the DTC

• DTC P062B is not set.
• The engine is running for greater than 5 s.
• The ignition voltage is greater than 11 V.
• The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0201, P0202, P0203, or P0204

The ECM detects the fuel injector control circuit is open for greater than 2 s.

P0261, P0264, P0267, or P0270

The ECM detects the fuel injector control - circuit is shorted to ground for greater than 2 s.

P0262, P0265, P0268, or P0271

The ECM detects the fuel injector control + circuit is shorted to voltage for greater than 2 s.

P1248, P1249, P124A, or P124B

The ECM detects the fuel injector control + circuit is shorted to the fuel injector control - circuit for greater than 2 s.

P2147, P2150, P2153, or P2156

The ECM detects the fuel injector control + circuit is shorted to ground for greater than 2 s.

P2148, P2151, P2154, or P2157

The ECM detects the fuel injector control + circuit is shorted to voltage for greater than 2 s.

Action Taken When the DTC Sets

DTCs P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, and P2157 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, and P2157 are Type A DTCs.

Diagnostic Aids

• Performing the fuel injector coil test may help isolate an intermittent condition. Refer to Fuel Injector Diagnosis.
• If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool Injector Control Circuit Status parameters. An Injector Control Circuit Status parameter will change from OK or Not Run to Malfunction if there is a condition with the circuit or a connection.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0685 or P1682 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

NOTE: The engine must be running for the scan tool Cylinder 1 - 4 Injector Control Circuit Status parameters to function.

3. Engine idling.

4. Verify with a scan tool the parameters listed below do not increment.

• Cylinder 1 Current Misfire Counter
• Cylinder 2 Current Misfire Counter
• Cylinder 3 Current Misfire Counter
• Cylinder 4 Current Misfire Counter
• If a parameter increments

Refer to Circuit/System Testing.

• Go to next step: If a parameter does not increment

5. Verify with a scan tool the parameters listed below display OK or Not Run.

• Cylinder 1 Injector Control Circuit Status
• Cylinder 2 Injector Control Circuit Status
• Cylinder 3 Injector Control Circuit Status
• Cylinder 4 Injector Control Circuit Status
• If OK or Not Run is not displayed

Refer to Circuit/System Testing.

• Go to next step: If OK or Not Run is displayed

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify the DTC does not set

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK.

Circuit/System Testing

1. Ignition OFF, all vehicle systems OFF, disconnect the harness connector at the K20 Engine Control Module. It may take up to 2 min for all vehicle systems to power down.

2. Test for infinite resistance between the appropriate Q17 Fuel Injector control + circuit and ground.

• If less than infinite resistance

1. Disconnect the harness connector of the Q17 Fuel Injector.
2. Test for infinite resistance between the Q17 Fuel Injector control + circuit and ground.
   • If less than infinite, repair the short to ground in the circuit.
   • Go to next step: If infinite resistance
3. Test for infinite resistance between the Q17 Fuel Injector control - circuit and ground.
   • If less than infinite, repair the short to ground in the circuit.
   • If infinite, replace the Q17 Fuel Injector.

• Go to next step: If infinite resistance

3. Ignition ON.

4. Test for less than 1 V between the Q17 Fuel Injector control + circuit and ground.

• If 1 V or greater

1. Disconnect the harness connector of the Q17 Fuel Injector, ignition ON.
2. Test for less than 1 V between the Q17 Fuel Injector control + circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, repair the short to voltage on the control - circuit.

• Go to next step: If less than 1 V

5. Ignition OFF.

6. Test for less than 3 Ω between the Q17 Fuel Injector control + circuit and control - circuit.

• If 3 Ω or greater

1. Disconnect the harness connector of the Q17 Fuel Injector.
2. Test for less than 2 Ω on the control + circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω
3. Test for less than 2 Ω on the control - circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the Q17 Fuel Injector.

• Go to next step: If less than 3 Ω

7. Replace the K20 Engine Control Module.

Component Testing

Fuel Injector Diagnosis

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Injector Replacement
• Control Module References for control module replacement, setup, and programming

DTC P0231, P0232, or P023F

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0231

Fuel Pump Control Circuit Low Voltage

DTC P0232

Fuel Pump Control Circuit High Voltage

DTC P023F

Fuel Pump Control Circuit

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) supplies voltage to the fuel pump driver control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump driver control module remains active for 2 s, unless the engine is in crank or run. While this voltage is being received, the fuel pump driver control module supplies a varying voltage to the fuel tank fuel pump module in order to maintain the desired fuel line pressure.

Conditions for Running the DTC

P0231

• The ignition voltage is between 9 - 32 V.
• The fuel pump enable circuit is commanded ON.
• The fuel pump current is less than 100 A.

P0232

• The ignition voltage is between 9 - 32 V.
• The fuel pump enable circuit is commanded OFF.
• The above conditions are met for 4 s.
• The DTC runs once per trip.

P023F

• The ignition voltage is between 9 - 32 V.
• The fuel pump enable circuit is commanded ON.

Conditions for Setting the DTC

P0231

The fuel pump driver control module detects that the fuel pump current is greater than 14.48 A for 1 s.

P0232

The fuel pump driver control module detects that the fuel pump control circuit voltage is greater than 3.86 V for 0.5 s when the voltage should be 0 V.

P023F

The fuel pump driver control module detects that the fuel pump current is less than 0.5 A and the fuel pump duty cycle is greater than 20 percent for 1 s.

Action Taken When the DTC Sets

• DTCs P0231 and P023F are Type A DTCs.
• DTC P0232 is a Type B DTC.

Conditions for Clearing the DTC

• DTCs P0231 and P023F are Type A DTCs.
• DTC P0232 is a Type B DTC.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

On vehicles equipped with a high pressure mechanical pump on Direct Fuel Injection engines, the vehicle may continue to run even though the pump in the fuel tank is not operating.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify the fuel pump turns ON and OFF when commanding the Fuel Pump Enable On and Off with a scan tool.

• If the fuel pump does not turn ON and OFF

Refer to Circuit/System Testing.

• Go to next step: If the fuel pump turns ON and OFF

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

5. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module and the X350 inline harness connector.

2. Test for less than 2 Ω in the low reference circuit end to end between the appropriate terminal at the body side of connector X350 and at the K111 Fuel Pump Driver Control Module.

• If 2 Ω or greater

Repair the open/high resistance in the circuit.

• Go to next step: If less than 2 Ω

3. Connect the harness connector at the K111 Fuel Pump Driver Control Module.

4. Ignition ON, connect a test lamp between the fuel pump control circuit terminal and the low reference circuit terminal at the body side of connector X350.

5. Verify the test lamp turns ON and OFF when commanding the Fuel Pump Enable On and Off with a scan tool.

• If the test lamp is always OFF

1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.
2. Test for infinite resistance between the fuel pump control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the fuel pump control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, test or replace the K111 Fuel Pump Driver Control Module.

• If the test lamp is always ON

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K111 Fuel Pump Driver Control Module, ignition ON.
2. Test for less than 1 V between the fuel pump control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, test or replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If the test lamp turns ON and OFF

6. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module and at the G12 Fuel Pump. It may take up to 2 minutes for all vehicle systems to power down.

7. Test for infinite resistance between the low reference circuit and ground.

• If less than infinite resistance

Repair the short to ground on the circuit.

• Go to next step: If infinite resistance

8. Test for less than 2 Ω in the low reference circuit end to end.

• If 2 Ω or greater

Repair the open/high resistance in the circuit.

• Go to next step: If less than 2 Ω

9. Test for infinite resistance between the fuel pump control circuit and ground.

• If less than infinite resistance

Repair the short to ground on the circuit.

• Go to next step: If infinite resistance

10. Test for less than 2 Ω in the fuel pump control circuit end to end.

• If 2 Ω or greater

Repair the open/high resistance in the circuit.

• Go to next step: If less than 2 Ω

11. Replace the G12 Fuel Pump.

Component Testing

Static Test

1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.

2. Connect a DMM, set on the diode setting, with the positive lead at terminal 16 and the negative lead at terminal 9 of the K111 Fuel Pump Driver Control Module 3. Test for 0.4 - 0.8 V between terminal 16 and terminal 9.

• If not between 0.4 - 0.8 V

Replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If between 0.4 - 0.8 V

4. Connect a DMM, set on the diode setting, with the positive lead at terminal 9 and the negative lead at terminal 16 of the K111 Fuel Pump Driver Control Module 5. Test for OL between terminal 9 and terminal 16.

• If not OL

Replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If OL

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD) for K111 Fuel Pump Driver Control Module replacement
• Fuel Tank Fuel Pump Module Replacement (FWD) or Fuel Tank Fuel Pump Module Replacement (AWD) for G12 Fuel Pump replacement

DTC P0234 or P0299

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0234

Engine Overboost

DTC P0299

Engine Underboost

Circuit Description

The boost pressure sensor is integrated with the intake air temperature (IAT) sensor 3. The boost pressure sensor measures the range of pressures between the turbocharger and the throttle body. The sensor used on this engine is a three atmosphere sensor. Pressure in this portion of the induction system is affected by engine speed, throttle opening, turbocharger boost pressure, IAT, barometric pressure (BARO), and the efficiency of the charge air cooler.

The sensor provides a signal voltage to the engine control module (ECM), relative to the pressure changes, on the boost pressure signal circuit. Under normal operation the greatest pressure that can exist in this portion of the induction system at ignition On, engine Off is equal to the BARO. When the vehicle is operated at wide-open throttle (WOT) the turbocharger can increase the pressure to near 240 kPa (34.8 psi). The lowest pressure that occurs is when the vehicle is idling or decelerating, and it is equal to BARO.

Conditions for Running the DTCs

• DTC P0010, P0011, P0013, P0014, P0016, P0017, P0033, P0034, P0035, P0068, P00C8, P00C9, P0111, P0112, P0113, P0114, P0116, P0122, P0123, P0128, P0222, P0223, P0236, P0237, P0238, P0243, P0245, P0246, P0601, P0604, P0606, P1682, P16A0, P16A1, P16F3, P2101, P2176, P2227, P2228, P2229, P2230 or P2261 is not set.
• The driver requested boost pressure level exceeds the level of the base boost pressure.
• The engine speed is between 1, 600 - 6, 000 RPM.

  The desired boost pressure is between 140 - 300 kPa (20.3 - 43.5 psi) The Barometric Pressure (BARO) is between 60 - 120 kPa (8.7 - 17.4 psi).

  The Engine Coolant Temperature (ECT) is between -40 to +120ºC (-40 to +248ºF).

  The Intake Air Temperature (IAT) is between -40 to +80ºC (-40 to +176ºF) The turbocharger wastegate is not under output device control.

  The turbocharger bypass valve is not under output device control.

  The DTCs run continuously when the above conditions have been met.

Conditions for Setting the DTC

P0234

The ECM detects that the actual boost pressure is greater than the desired boost pressure by a calibrated amount for greater than 3 s.

P0299

The ECM detects that the actual boost pressure is less than the desired boost pressure by a calibrated amount for greater than 3 s.

Action Taken When the DTC Sets

• DTCs P0234 and P0299 are Type B DTCs.
• The ECM will disable boost control and limit the system to mechanical boost only, resulting in a substantial decrease in engine power.

Conditions For Clearing the MIL/DTC

DTCs P0234 and P0299 are Type B DTCs.

Diagnostic Aids

• The charge air cooler is connected to the turbocharger and to the throttle body by flexible duct work that requires the use of special high torque fastening clamps. These clamps cannot be substituted. In order to prevent any type of air leak when servicing the ductwork, the tightening specifications and proper positioning of the clamps is critical, and must be strictly adhered to.
• Use a solution of dish soap and water in a spray bottle to pinpoint any air leaks.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

GE-23738-A Vacuum Pump

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition On.

2. Verify DTC P0106, P0107, P0108, P0236, P0237, P0238, P0243, P0245, P0246, P2227, P2228, P2229, or P2230 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

3. Verify the scan tool BARO Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table for the current testing altitude.

• If not within the range.

Refer to DTC P2227-P2230.

• Go to next step: If within the range.

4. Verify the scan tool MAP Sensor and BARO Sensor parameters are within 3 kPa (0.4 psi).

• If not within 3 kPa (0.4 psi).

Refer to DTC P0106.

• Go to next step: If within 3 kPa (0.4 psi).

5. Verify the scan tool Boost Pressure Sensor and BARO Sensor parameters are within 3 kPa (0.4 psi).

• If not within 3 kPa (0.4 psi).

Refer to DTC P0236.

• Go to next step: If within 3 kPa (0.4 psi).

6. Verify a click is heard or felt from the Q40 Turbocharger Bypass Solenoid Valve when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• If a click is not heard or felt

Refer to DTC P0033-P0035.

• Go to next step: If a click is heard or felt

7. Verify the parameters listed below do not display Malfunction when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• Turbocharger Bypass Solenoid Valve Control Circuit High Voltage Test Status
• Turbocharger Bypass Solenoid Valve Control Circuit Open Test Status
• Turbocharger Bypass Solenoid Valve Control Circuit Low Voltage Test Status
• If Malfunction is displayed

Refer to DTC P0033-P0035.

• Go to next step: If Malfunction is not displayed

8. Verify a series of clicks, which increase in frequency, are heard or felt from the Q42 Turbocharger Wastegate Solenoid Valve when commanding the Turbocharger Wastegate Solenoid Valve between 15 - 100 % with a scan tool.

• If a series of clicks in increasing frequency are not heard or felt

Refer to DTC P0243, P0245, or P0246.

• Go to next step: If a series of clicks in increasing frequency is heard or felt

9. Verify the parameters listed below do not display Malfunction when commanding the Turbocharger Wastegate Solenoid Valve between 15 - 100 % with a scan tool.

• Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage Test Status
• Turbocharger Wastegate Solenoid Valve Control Circuit Open Test Status
• Turbocharger Wastegate Solenoid Valve Control Circuit Low Voltage Test Status
• If Malfunction is displayed

Refer to DTC P0243, P0245, or P0246.

• Go to next step: If Malfunction is not displayed

10. Verify the scan tool MAP Sensor parameter and the Boost Pressure Sensor parameter are within 20 kPa (2.9 psi) during a WOT acceleration at the time of the 1-2 shift.

• If not within 20 kPa (2.9 psi)

Refer to Circuit/System Testing.

• Go to next step: If within 20 kPa (2.9 psi)

11. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

12. Verify a DTC does not set.

• If a DTC sets

Refer to Circuit/System Testing

• Go to next step: If a DTC does not set

13. All OK

Circuit/System Testing

1. Verify the conditions listed below do not exist:

• Loose clamps, cracks or other damage in the air intake duct system
• Collapsed or restricted intake duct system
• Restricted air filter
• Any air flow restriction
• Any air leak between the turbocharger and the throttle body, including the charge air cooler assembly
• Splits, kinks or improper connections at the vacuum hoses
• Any vacuum leak
• Restricted, leaking or incorrect routing of hoses going to the components listed below:
  • Q42 Turbocharger Wastegate Solenoid Valve
  • Turbocharger wastegate actuator
  • Turbocharger
• Missing, restricted or leaking exhaust components. Refer to Symptoms - Engine Exhaust.
• Exhaust leak between the turbocharger and the exhaust manifold
• Restricted or leaking turbocharger oil supply line
• Loose or incorrect installation of any components
• If a condition exists

Repair or replace the affected component as necessary.

• Go to next step: If none of the conditions exist

2. Ignition Off, disconnect the turbocharger wastegate solenoid valve supply hose at the turbocharger and apply 51 kPa (15 inches Hg) of vacuum to the hose with the GE 23738-A , ignition On.

3. Verify the pressure decreases to 0 kPa (0 inches Hg) when commanding the Turbocharger Wastegate Solenoid Valve to 15 % with a scan tool.

• The pressure does not decrease to 0 kPa (0 inches Hg)

Replace the Q42 Turbocharger Wastegate Solenoid Valve

• Go to next step: The pressure decreases to 0 kPa (0 inches Hg)

4. Connect the turbocharger wastegate solenoid valve supply hose to the turbocharger.

5. Disconnect the hose from the turbocharger wastegate actuator and connect the exhaust/pressure port of the GE 23738-A , or a suitable hand pressure pump, to the actuator.

6. Verify the wastegate actuator rod moves when applying pressure to the actuator.

• If the actuator does not move

1. Disconnect the wastegate actuator arm from the wastegate.
2. Verify the wastegate actuator rod moves when applying pressure to the actuator.
   • If the actuator does not move, replace the turbocharger wastegate actuator.
   • If the actuator moves, replace the turbocharger.

• Go to next step: If the actuator moves

NOTE: Leave harness connector connected or re-connect it after removing valve.

7. Ignition Off, remove the Q40 Turbocharger Bypass Solenoid Valve from the turbocharger, ignition On.

8. Verify the Q40 Turbocharger Bypass Solenoid Valve plunger retracts and extends when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• The valve plunger does not retract and extend

Replace the Q40 Turbocharger Bypass Solenoid Valve

• Go to next step: The valve plunger retracts and extends

9. Verify the conditions listed below do not exist with the turbocharger assembly. Refer to Camshaft Cover and Compressor Air Intake Turbocharger Cleaning and Inspection

• Cracked, damaged or worn turbine blades
• Restricted wastegate, turbine, ports or passages
• Foreign material
• A condition exists

Repair or replace the turbocharger as necessary

• Go to next step: None of the conditions exist

10. Replace the turbocharger.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Turbocharger Replacement
• Turbocharger Bypass Valve Solenoid Replacement
• Turbocharger Wastegate Actuator Replacement
• Turbocharger Wastegate Regulator Solenoid Valve Replacement
• Control Module References for ECM replacement, programming, and setup

DTC P0236

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0236

Turbocharger Boost Sensor Performance

Circuit Description

The boost pressure sensor is integrated with the turbocharger boost/intake air temperature sensor. The boost pressure sensor measures the range of pressures between the turbocharger and the throttle body.

The sensor used on this engine is a three atmosphere sensor. Pressure in this portion of the induction system is affected by engine speed, throttle opening, turbocharger boost pressure, Intake air temperature (IAT), barometric pressure (BARO), and the efficiency of the charge air cooler.

The sensor provides a signal voltage to the engine control module (ECM), relative to the pressure changes. Under normal operation the greatest pressure that can exist in this portion of the induction system at ignition ON, engine OFF is equal to the BARO. When the engine is operated at wide-open throttle (WOT) the turbocharger can increase the pressure to near 240 kPa (34.8 psi). The pressure is equal to the BARO when the engine is idling or decelerating.

Conditions for Running the DTC

• DTC P0106, P0107, P0108, P0237, P0238, P2227, P2228, P2229, or P2230 is not set.
• DTC P0106, P0107, P0108, P0237, or P0238 is not pending.
• Ignition is ON.
• Engine is OFF.
• The time between current ignition cycle and the last time the engine was running is greater than 10 s.
• The DTC runs continuously when the above conditions have been met.

  OR

• DTC P0102, P0103, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0128, P0237, P0238, P0335, P0336, P2227, P2228, P2229 or P2230 is not set.
• DTC P0112, P0113, P0117, or P0118 is not pending.
• Engine speed is between 400 - 6, 000 RPM.
• Engine Coolant Temperature (ECT) is between -7 to +125ºC (19.4 - 257ºF).
• Intake Air Temperature (IAT) is between -20 to +125ºC (-4 to +257ºF).
• The DTC runs continuously when the above conditions have been met.

Conditions for Setting the DTC

• The ECM detects that the boost pressure sensor signal is not within range of a model derived from engine speed, the BARO sensor, the MAF sensor, the MAP sensor, the throttle position sensor and the turbocharger boost pressure sensor when the engine is running.

  OR

• The ECM detects that the boost pressure sensor signal is less than 50 kPa (7.3 psi) or greater than 115 kPa (16.7 psi) when the ignition is ON and the engine is NOT rotating.

  OR

• The ECM detects that the difference between MAP and BARO is less than or equal to 10 kPa and the difference between turbocharger boost pressure and MAP is greater than 10 kPa and the difference between turbocharger boost pressure and BARO is greater than 10 kPa when the ignition is ON and the engine is NOT rotating.

Action Taken When the DTC Sets

DTC P0236 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0236 is a Type B DTC.

Diagnostic Aids

• The charge air cooler is connected to the turbocharger and to the throttle body by flexible duct work that requires the use of special high torque fastening clamps. These clamps cannot be substituted. In order to prevent any type of air leak when servicing the duct work, the tightening specifications and proper positioning of the clamps is critical, and must be strictly adhered to.
• Use a smoke generating device or a solution of dish soap and water in a spray bottle to pinpoint any suspected air leaks in the induction system and in the charge air cooler assembly.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

2. If you were sent here from DTC P0068, P0101, P0106, P0121, or P1101 refer to Circuit/System Testing.

3. Ignition ON.

4. Verify the scan tool Throttle Body Idle Airflow Compensation parameter is less than 90%.

• If 90% or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90%

5. Verify the scan tool Throttle Position Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.

• If Disagree

Refer to DTC P0121-P0123, P0222, P0223, P16A0-P16A2, or P2135.

• Go to next step: If Agree

6. Verify the scan tool BARO parameter is within the range specified in the Altitude Versus Barometric Pressure table, for the current vehicle testing altitude.

• BARO is not in range

Refer to DTC P2227-P2230.

• Go to next step: BARO is within range

7. Verify the scan tool MAP Sensor pressure and BARO parameters are within 3 kPa (0.4 psi).

• The parameters are not within 3 kPa (0.4 psi).

Refer to DTC P0106.

• Go to next step: The parameters are within 3 kPa (0.4 psi).

8. Engine idling.

9. Verify the scan tool MAP Sensor pressure parameter is between 26 - 52 kPa (3.8 - 7.5 psi) and changes with accelerator pedal input.

• If not between 26 - 52 kPa (3.8 - 7.5 psi) or does not change

Refer to DTC P0106.

• Go to next step: If between 26 - 52 kPa (3.8 - 7.5 psi) and changes

10. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.

1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3, 000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.

• The MAF Sensor parameter does not change smoothly and gradually

Refer to DTC P0101.

• Go to next step: The MAF Sensor parameter changes smoothly and gradually

12. Verify the scan tool MAP Sensor parameter and the Boost Pressure Sensor parameter are within 20 kPa (2.9 psi) during a WOT acceleration at the time of the 1-2 shift.

• The parameters are not within 20 kPa (2.9 psi)

Refer to Circuit/System Testing.

• Go to next step: The parameters are within 20 kPa (2.9 psi)

13. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

14. Verify a DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

15. All OK.

Circuit/System Testing

1. Verify that DTC P0237 or P0238 is not set.

• If a DTC is set

Refer to DTC P0237 or P0238.

• Go to next step: If none of the DTCs are set

2. Verify the conditions listed below do not exist:

• Loose clamps, cracks, or other damage in the air intake duct system
• Collapsed or restricted air intake duct system
• Restricted air filter
• Splits, kinks or improper connections at the vacuum hoses
• Missing, restricted or leaking exhaust components - Refer to Symptoms - Engine Exhaust.
• Vacuum leaks at the intake manifold and throttle body
• If a condition exists

Repair as necessary.

• Go to next step: If none of the conditions exist

3. Replace the B111B turbocharger boost/intake air temperature sensor.

Repair Instructions

• Perform the Diagnostic Repair Verification after completing the repair.

  Intake Air Pressure and Temperature Sensor Replacement for turbocharger boost/intake air temperature sensor replacement.

• Control Module References for engine control module replacement, programming, and setup

DTC P0237 or P0238

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0237

Turbocharger Boost Sensor Circuit Low Voltage

DTC P0238

Turbocharger Boost Sensor Circuit High Voltage

Diagnostic Fault Information

Typical Scan Tool Data

Boost Pressure Sensor

Circuit Description

The boost pressure sensor is integrated with the turbocharger boost/intake air temperature sensor. The boost pressure sensor measures the range of pressures between the turbocharger and the throttle body.

The sensor used on this engine is a three atmosphere sensor. Pressure in this portion of the induction system is affected by engine speed, throttle opening, turbocharger boost pressure, Intake air temperature (IAT), barometric pressure (BARO), and the efficiency of the charge air cooler.

The sensor provides a signal voltage to the engine control module (ECM), relative to the pressure changes. Under normal operation the greatest pressure that can exist in this portion of the induction system at ignition ON, engine OFF is equal to the BARO. When the engine is operated at wide-open throttle (WOT) the turbocharger can increase the pressure to near 240 kPa (34.8 psi). The pressure is equal to the BARO when the engine is idling or decelerating.

Conditions for Running the DTC

• Ignition is ON or the engine is running.
• The DTCs run continuously when the above conditions have been met.

Conditions for Setting the DTC

P0237

The ECM detects that the boost pressure sensor voltage is less than 0.9 V for greater than 5 s.

P0238

The ECM detects that the boost pressure sensor voltage is greater than 3.9 V for greater than 5 s.

Action Taken When the DTC Sets

• DTCs P0237 and P0238 are Type B DTCs.
• The ECM will disable boost control and limit the system to mechanical boost only, resulting in a substantial decrease in engine power.

Conditions for Clearing the MIL/DTC

DTCs P0237 and P0238 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

2. Verify the scan tool BARO parameter is within the range specified in the Altitude Versus Barometric Pressure table, for the current vehicle testing altitude.

• BARO is not in range

Refer to DTC P2227-P2230.

• Go to next step: BARO is within range

3. Verify the scan tool Boost Pressure Sensor pressure and BARO parameters are within 3 kPa (0.4 psi).

• The parameters are not within 3 kPa (0.4 psi).

Refer to Circuit/System Testing

• Go to next step: The parameters are within 3 kPa (0.4 psi).

4. Verify the scan tool MAP Sensor parameter and the Boost Pressure Sensor parameter are within 20 kPa (2.9 psi) during a WOT acceleration at the time of the 1-2 shift.

• The parameters are not within 20 kPa (2.9 psi)

Refer to Circuit/System Testing.

• Go to next step: The parameters are within 20 kPa (2.9 psi)

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify a DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF, and all vehicle systems OFF, disconnect the harness connector at the B111B turbocharger boost/intake air temperature sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 1 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the X1 harness connector at the K20 engine control module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 engine control module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the X1 harness connector at the K20 engine control module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 engine control module

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

• If greater than 5.2 V

1. Ignition OFF, disconnect the X1 harness connector at the K20 engine control module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 engine control module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool Boost Pressure Sensor voltage parameter is less than 0.2 V.

• If 0.2 V or greater

1. Ignition OFF, disconnect the X1 harness connector at the K20 engine control module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal 4 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 engine control module.

• Go to next step: If less than 0.2 V

6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the 5 V reference circuit terminal 3.

7. Verify the scan tool Boost Pressure Sensor voltage parameter is greater than 4.5 V.

• If 4.5 V or less

1. Ignition OFF, disconnect the X1 harness connector at the K20 engine control module.
2. Test for infinite resistance between the signal circuit terminal 4 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, replace the K20 engine control module.

• Go to next step: If greater than 4.5 V

8. Test or replace the B111B turbocharger boost/intake air temperature sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Intake Air Pressure and Temperature Sensor Replacement for turbocharger boost/intake air temperature sensor replacement
• Control Module References for ECM replacement, programming, and setup

DTC P0243, P0245, or P0246

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0243

Turbocharger Wastegate Solenoid Valve Control Circuit

DTC P0245

Turbocharger Wastegate Solenoid Valve Control Circuit Low Voltage

DTC P0246

Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The dual-scroll turbocharger incorporates a wastegate that is controlled by the engine control module (ECM) by means of a pulse width modulation (PWM) solenoid, to regulate the pressure ratio of the compressor. An ECM controlled compressor bypass valve is integrated into the unit to prevent compressor surging and damage from vibrations by opening during abrupt closed throttle conditions.

The bypass valve is open during closed throttle deceleration conditions to allow air to recirculate in the turbocharger and maintain compressor speed.

As engine load and RPM increase, the turbocharger bypass valve is commanded closed by the ECM. As soon as the throttle closes, the valve is commanded open to allow the turbocharger air to recirculate to prevent compressor surging.

Conditions for Running the DTCs

• Ignition is On or the engine is running.
• Battery voltage is between 11 - 32 V.
• The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTCs

P0243

The ECM detects an open circuit on the turbocharger wastegate solenoid control circuit for greater than 2 s.

P0245

The ECM detects a short to ground on the turbocharger wastegate solenoid control circuit for greater than 2 s.

P0246

The ECM detects a short to voltage on the turbocharger wastegate solenoid control circuit for greater than 2 s.

Action Taken When the DTCs Set

• DTCs P0243, P0245, and P0246 are Type B DTCs.
• The ECM will disable boost control and limit the system to mechanical boost only, resulting in a substantial decrease in engine power.

Conditions for Clearing the MIL/DTCs

DTCs P0243, P0245, and P0246 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition On 2. Verify a series of clicks, which increase in frequency, are heard or felt from the Q42 Turbocharger Wastegate Solenoid Valve when commanding the Turbocharger Wastegate Solenoid Valve between 15 - 100 % with a scan tool.

• If a series of clicks in increasing frequency are not heard or felt

Refer to Circuit/System Testing.

• Go to next step: If a series of clicks in increasing frequency is heard or felt

3. Verify the parameters listed below do not display Malfunction when commanding the Turbocharger Wastegate Solenoid Valve between 15 - 100 % with a scan tool.

• Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage Test Status
• Turbocharger Wastegate Solenoid Valve Control Circuit Open Test Status
• Turbocharger Wastegate Solenoid Valve Control Circuit Low Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify a DTC does not set.

• If a DTC sets

Refer to Circuit/System Testing

• Go to next step: If a DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition Off, disconnect the harness connector at the Q42 Turbocharger Wastegate Solenoid Valve, ignition On.

2. Verify a test lamp illuminates between the ignition circuit terminal 1 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition Off.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition Off, remove the test lamp.

NOTE: A short circuit in any component supplied by the fuse may cause the fuse to open and set a DTC when the component is activated.

2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components supplied by the fuse and replace as necessary.

• Go to next step: If the test lamp illuminates

3. Verify that a test lamp does not illuminate between the control circuit terminal 2 and the ignition circuit terminal 1.

• If the test lamp illuminates

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage Test Status parameter is OK when commanding the Turbocharger Wastegate Solenoid Valve between 15 - 100 % with a scan tool.

• If OK is not displayed

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal 2 and the ignition circuit terminal 1.

7. Verify the scan tool Turbocharger Wastegate Solenoid Valve Control Circuit High Voltage Test Status parameter is Malfunction.

• If Malfunction is not displayed

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If Malfunction is displayed

8. Test or replace the Q42 Turbocharger Wastegate Solenoid Valve.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Turbocharger Wastegate Regulator Solenoid Valve Replacement
• Control Module References for ECM replacement, programming and setup

DTC P0300-P0304

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0300

Engine Misfire Detected

DTC P0301

Cylinder 1 Misfire Detected

DTC P0302

Cylinder 2 Misfire Detected

DTC P0303

Cylinder 3 Misfire Detected

DTC P0304

Cylinder 4 Misfire Detected

Circuit/System Description

The engine control module (ECM) uses information from the crankshaft position sensor and the camshaft position sensor to determine when a engine cylinder misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the ECM can detect individual cylinder misfire events.

Extreme cylinder misfire events can cause catalytic converter damage. The malfunction indicator lamp (MIL) will flash when the conditions for catalytic converter damage are present. DTCs P0301 through P0304 correspond to cylinders 1 through 4. When the ECM detects that one or more specific cylinders are misfiring, the DTC for the respective misfiring cylinder will set and up to 2 of the corresponding fuel injectors are disabled for a minimum of 30 s. The ECM will then re-enable the fuel injector and, after approximately 200 engine revolutions, will determine if the misfire is still present. If the misfire is still present, the ECM will disable the fuel injector again repeating the process. If the misfire is not present, the fuel injector will remain enabled by the ECM. In Spark Ignition Direct Injection (SIDI) system applications, if a fuel injector fault DTC is set during a misfire event, the ECM will not re-enable the injector.

Conditions for Running the DTC

• DTC P0010, P0011, P0013, P0014, P0016, P0017, P0068, P00C8, P00C9, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0117, P0118, P0119, P0122, P0123, P0191, P0192, P0193, P0222, P0223, P0335, P0336, P0340, P0341, P0365, P0366, P0601, P0604, P0606, P0651, P16A0, P16A1, P16A2, P16F3, P2101, P2135, P2227, P2228, P2229, or P2230 is not set.
• The engine speed is less than 1, 000 RPM and DTC P0315 is set.
• The engine speed is greater than 1, 050 RPM.
• The crankshaft position and camshaft position sensors are synchronized.
• The engine coolant temperature (ECT) is between -12 and 127ºC (10 - 261ºF).
• If the ECT is colder than -12ºC (10ºF) at start-up, this diagnostic will not run until the ECT is between 21 - 127ºC (70 - 261ºF).
• The battery voltage is between 9 - 32 V.
• The ECM is not detecting a rough road signal.
• The fuel level is at least 11%.
• The ECM is not in fuel cut-off or deceleration fuel cut-off mode.

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P0300

The ECM detects a crankshaft rotation speed variation indicating a misfire rate sufficient to cause emissions levels to exceed a predetermined value or a misfire rate high enough to cause catalyst damage.

P0301, P0302, P0303, or P0304

The ECM detects a crankshaft rotation speed variation indicating a single cylinder misfire rate sufficient to cause emissions levels to exceed mandated standards.

Action Taken When the DTC Sets

• DTCs P0300 - P0304 are Type B DTCs.
• The ECM will flash the malfunction indicator lamp (MIL) when a catalyst damaging level of misfire is present.
• If a hybrid application, engine idle speed will increase to between 1750-2500 RPM.

Conditions for Clearing the DTC

DTCs P0300 - P0304 are Type B DTCs.

Diagnostic Aids

• A misfire DTC could be caused by an excessive vibration from sources other than the engine.

  Inspect for the conditions listed below:

  • A tire or wheel that is out of round or out of balance
  • Variable thickness brake rotors
  • An unbalanced drive shaft
  • Certain rough road conditions
  • Transmission operation
  • A damaged or defective accessory drive component or belt
• High resistance in the circuits of the injectors or ignition coils may set a misfire DTC without setting an injector or ignition coil DTC. Test the injector and ignition coil circuits of the affected cylinder (s) for a high resistance if you suspect a condition. Also check for poor terminal tension at the injectors and ignition coils of the affected cylinder (s).
• If the condition is intermittent, wiggle the related wiring harnesses and connectors, with the ignition/vehicle on or engine running, while monitoring the scan tool circuit status parameters for the component. The parameters will display if there is a condition with the circuit or a connection.
• A condition in the heated O2 sensor (HO2S) heater control circuits may set a DTC P0300.

Reference Information

Description and Operation

• Electronic Ignition System Description
• Fuel System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL26792 Spark Tester

For equivalent regional tools, refer to Special Tools (diagnostic tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

NOTE: Before starting the engine, review the freeze frame failure records data to determine if the misfire sets during a cold start or at operating temperature. If there is a cold start condition and the engine is started, the engine will need to be cooled down before the next attempt to start the engine within the fail conditions.

If this a hybrid application and the hybrid battery is fully charged, the engine runs at a very low load since the hybrid battery cannot accept any additional charge. At this very low engine load, engine misfire may not be detected. It may be necessary to drive the vehicle in battery only propulsion mode in order to discharge the hybrid battery before diagnosis can be performed.

1. If this is a hybrid application, skip to step 4.

2. Engine Running at normal operating temperature.

3. Verify there is no abnormal engine noise.

• If abnormal engine noise is present

Refer to Symptoms - Engine Mechanical.

• Go to next step: If abnormal engine noise is not present

4. Perform the scan tool Crankshaft Position Variation Learn procedure.

5. Verify no DTCs are set.

• If any DTCs other than P0300 - P0304 are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• If DTC P0300 - P0304 is set

Refer to Circuit/System Testing.

• Go to next step: If no DTCs are set

6. Verify the scan tool Cylinder 1 - 4 Current Misfire Counter parameters do not increment.

• If increments

Refer to Circuit/System Testing.

• Go to next step: If does not increment

7. Engine Running, perform the Cylinder Power Balance Test with a scan tool.

8. Verify the engine speed changes when each injector is disabled and then enabled.

• If engine speed does not change

Refer to Circuit/System Testing.

• Go to next step: If engine speed does change

9. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

10. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

11. All OK.

Circuit/System Testing

1. Verify none of the following conditions listed below exist:

• Damage, carbon tracking, or fluid intrusion of the spark plug boots and/or spark plugs
• Vacuum hose splits, kinks, and incorrect connections
• Engine vacuum leaks
• Crankcase ventilation system for vacuum leaks
• Fuel pressure that is too low or too high. Refer to Fuel System Diagnosis.
• Contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Exhaust system restrictions
  • If a condition exists

    Repair or replace as necessary.

  • Go to next step: If no conditions exist

NOTE: An erratic or weak spark is considered a no spark condition.

2. Ignition OFF, remove the appropriate T 8 Ignition Coil from the spark plug and connect the EL 26792 HEI Spark Tester to the spark plug boot, engine Cranking.

3. Verify the spark output.

• If no output or the output is weak

Refer to Electronic Ignition System Diagnosis.

• Go to next step: If the output is good

4. Ignition OFF.

5. Verify the conditions listed below. Refer to Ignition System Specifications.

• The correct spark plug type
• The correct spark plug gap
• The correct spark plug torque
• If a condition exists

Repair or replace as necessary.

• Go to next step: If no conditions exist

6. Exchange the suspect spark plug with another cylinder that is operating correctly.

7. Engine Running.

8. Verify the scan tool Cylinder 1 - 4 Current Misfire Counter does not increment for the cylinder where the suspect spark plug was installed.

• If increments

Replace the spark plug.

• Go to next step: If does not increment

9. Test or inspect for the conditions listed below:

• A lean or rich Q17 Fuel Injector - Refer to Fuel Injector Diagnosis.
• An engine mechanical condition - Refer to Symptoms - Engine Mechanical.

Repair Instructions

• Ignition Coil Replacement
• Spark Plug Replacement

Repair Verification

1. Install any components or connectors that have been removed or replaced during diagnosis.

2. Perform any adjustment, programming or setup procedures that are required when a component or module is removed or replaced.

3. Clear the DTCs.

4. Turn OFF the ignition for 60 s.

5. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

6. Engine Running, verify the scan tool Cylinder 1 - 4 Current Misfire Counter parameters do not increment.

• If the misfire counter parameters increment, a misfire condition still exists.

7. To verify that the performance of the catalytic converter has not been affected by the condition that set this DTC, perform the Repair Verification for DTC P0420. Refer to DTC P0420.

DTC P0315

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0315

Crankshaft Position System Variation Not Learned

Circuit/System Description

The crankshaft position sensor variation or reluctor ring learn is used to calculate reference period errors caused by slight tolerance variations in the crankshaft and the crankshaft position sensor. The calculated error allows the ECM to accurately compensate for reference period variations. This enhances the ability of the ECM to detect misfire events over a wider range of engine speed and load. The compensation values are stored in ECM memory after a learn procedure has been performed.

Conditions for Running the DTC

Engine=Running

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

Crankshaft Position Variation Learn=Not Learned

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type A DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type A DTC

Diagnostic Aids

This test procedure requires that the vehicle battery has passed a load test and is completely charged.

Refer to: Battery Inspection/Test

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode.

2. Perform the scan tool learn/reset function: Crankshaft Position Variation Learn.

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Replace the component: K20 Engine Control Module

• Go to next step: If the DTC is not set

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

For control module replacement, programming, and setup refer to: Control Module References

DTC P0324, P0326, P0331, P06B6, or P06B7

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0324

Knock Sensor System Performance

DTC P0326

Knock Sensor 1 Performance

DTC P0331

Knock Sensor 2 Performance

DTC P06B6

Control Module Knock Sensor Processor 1 Performance

DTC P06B7

Control Module Knock Sensor Processor 2 Performance

Diagnostic Fault Information

Circuit/System Description

The knock sensors enable the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The knock sensors produce an alternating current (AC) voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the two knock sensor signals. The ECM receives each knock sensor signal through a dedicated circuit. The ECM learns a minimum knock sensor noise level for all of the engine speed ranges and monitors the normal knock sensor signal. The ECM monitors the internal knock sensor processor test circuits which perform the open circuit diagnostic.

Conditions for Running the DTCs

P0324

• Engine is running for 2 s or greater.
• Engine speed is 8, 500 RPM or less.
• Engine air flow is between 0 - 2000 mg per cylinder.
• The engine coolant temperature (ECT) is -40ºC (-40ºF) or warmer.
• The intake air temperature (IAT) sensor is -40ºC (-40ºF) or warmer.

  AND

• Engine speed is 550 RPM or greater for 300 or more cumulative revolutions.

  OR

• Engine speed is 8500 RPM or greater for 400 or more cumulative revolutions.

P0326 and P0331

• Engine is running for 2 s or greater.
• Engine speed is 8, 500 RPM or less.
• Engine air flow is between 20 - 2000 mg per cylinder.
• The engine coolant temperature (ECT) is -40ºC (-40ºF) or warmer.
• The intake air temperature (IAT) sensor is -40ºC (-40ºF) or warmer.

  AND

• Engine speed is 500 RPM or greater for 200 or more cumulative revolutions.

  OR

• Engine speed is 2000 RPM or greater for 200 or more cumulative revolutions.

  OR

• Engine speed is 8500 RPM or greater for 200 or more cumulative revolutions.

P06B6 and P06B7

• Engine is running for 2 s or greater.
• Engine speed is between 400 - 8, 500 RPM for 150 or more cumulative revolutions.
• Engine air flow is between 20 - 2000 mg per cylinder.

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTCs

P0324

The ECM detects that either knock sensor signal performance is out of the normal calibrated range due to excessive engine knock on a per cylinder basis.

P0326

The ECM detects that the knock sensor 1 signal performance is out of the normal calibrated range due to a low signal level.

P0331

The ECM detects that the knock sensor 2 signal performance is out of the normal calibrated range due to a low signal level.

P06B6 and P06B7

The ECM has detected a fault in the knock sensor processor open circuit diagnostic internal test circuit.

Action Taken When the DTCs Set

• DTCs P0324, P0326, P0331, P06B6, and P06B7 are Type B DTCs.
• The ignition timing is retarded to reduce the potential of engine damaging spark knock.

Conditions for Clearing the DTCs

DTCs P0324, P0326, P0331, P06B6, and P06B7 are Type B DTCs.

Reference Information

Description and Operation

Electronic Ignition System Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Engine Running.

2. Verify DTC P0325, P0327, P0328, P0330, P0332, P0333, P06B6, or P06B7 is not set.

• If DTC P0325, P0327, P0328, P0330, P0332, or P0333 is set with P06B6 or P06B7

Refer to DTC P0325, P0327, P0328, P0330, P0332, or P0333.

• If only DTC P06B6 or P06B7 is set

Replace the K20 Engine Control Module.

• Go to next step: If none of the DTCs are set

3. Ignition OFF.

4. Verify none of the conditions listed below exist:

• B68 Knock Sensor or wiring harness damage.
• Incorrect B68 Knock Sensor installation. Refer to Fastener Specifications.
• B68 Knock Sensor and engine mounting surface burrs, casting flash, and foreign material.
• Close proximity of hoses, brackets, and engine wiring.
• Loose brackets.
• Loose or broken accessory drive belts, brackets, components.
• An engine mechanical condition. Refer to Symptoms - Engine Mechanical.
• Contaminated or poor quality fuel.
• If a condition exists

Repair or replace as necessary.

• Go to next step: If no conditions exist

5. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Test or replace the appropriate B68 Knock Sensor.

• Go to next step: If the DTC does not set

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Knock Sensor Replacement (Position 2) or Knock Sensor Replacement (Position 1)
• Control Module References for engine control module replacement, programming, and setup.

DTC P0325, P0327, P0328, P0330, P0332, or P0333

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0325

Knock Sensor 1 Circuit

DTC P0327

Knock Sensor 1 Circuit Low Voltage

DTC P0328

Knock Sensor 1 Circuit High Voltage

DTC P0330

Knock Sensor 2 Circuit

DTC P0332

Knock Sensor 2 Circuit Low Voltage

DTC P0333

Knock Sensor 2 Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The knock sensors enable the engine control module (ECM) to control the ignition timing for the best possible performance while protecting the engine from potentially damaging levels of detonation. The knock sensors produce an alternating current (AC) voltage signal that varies depending on the vibration level during engine operation. The ECM adjusts the spark timing based on the amplitude and the frequency of the two knock sensor signals. The ECM receives each knock sensor signal through a dedicated circuit. The ECM learns a minimum knock sensor noise level for all of the engine speed ranges and monitors the normal knock sensor signal. The ECM monitors the internal knock sensor processor test circuits which perform the open circuit diagnostic.

Conditions for Running the DTCs

P0325 and P0330

• Engine is running for 2 s or greater.
• Engine speed is between 400 - 5, 500 RPM for 75 or more cumulative revolutions.
• Engine air flow is between 20 - 2000 mg per cylinder.
• The engine coolant temperature (ECT) is -40ºC (-40ºF) or warmer.
• The intake air temperature (IAT) sensor 1 is -40ºC (-40ºF) or warmer.

P0327, P0328, P0332, and P0333

Engine speed is less than 8, 500 RPM.

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTCs

P0325

The ECM detects knock sensor 1 signal circuit is open.

P0327

The ECM detects knock sensor 1 signal circuit is shorted to ground.

P0328

The ECM detects knock sensor 1 signal circuit is shorted to voltage.

P0330

The ECM detects knock sensor 2 signal circuit is open.

P0332

The ECM detects knock sensor 2 signal circuit is shorted to ground.

P0333

The ECM detects knock sensor 2 signal circuit is shorted to voltage.

Action Taken When the DTCs Set

• DTCs P0325, P0327, P0328, P0330, P0332, and P0333 are Type B DTCs.
• The ignition timing is retarded to reduce the potential of engine damaging spark knock.

Conditions for Clearing the DTCs

DTCs P0325, P0327, P0328, P0330, P0332, and P0333 are Type B DTCs.

Diagnostic Aids

The following conditions listed below may cause a knock sensor DTC to set:

• Sensor damage.
• Knock sensor and engine mounting surface burrs, casting flash, and foreign material.
• Close proximity of hoses, brackets, and engine wiring.
• Loose brackets.
• Loose or broken accessory drive belts, brackets, components.
• An engine mechanical condition. Refer to Symptoms - Engine Mechanical.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Electronic Ignition System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Engine Running.

2. Verify DTC P0325, P0327, P0328, P0330, P0332, or P0333, is not set.

• If the DTC is set

Refer to Circuit/System Testing.

• Go to next step: If the DTC is not set

3. Verify the appropriate B68 Knock Sensor mounting bolt is properly tightened. Refer to Fastener Specifications.

• If not tightened to the correct specification

Repair a necessary.

• Go to next step: If tightened to the correct specification

4. Verify the scan tool parameters listed below display No while moving the related harnesses and connectors of the B68 Knock Sensor.

• Cylinder 1 Knock Detected
• Cylinder 2 Knock Detected
• Cylinder 3 Knock Detected
• Cylinder 4 Knock Detected
• If No is not displayed

Repair the wiring harness or connectors.

• Go to next step: If No is displayed

5. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate B68 Knock Sensor, ignition ON.

2. Test for 1 - 2 V between the low signal circuit terminal 2 or B and ground.

• If less than 1 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the low signal circuit terminal 2 or B and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance.
3. Test for less than 2 Ω in the low signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the low signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 1 - 2 V

3. Test for 2 - 4 V between the high signal circuit terminal 1 or A and ground.

• If less than 2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the high signal circuit terminal 1 or A and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance.
3. Test for less than 2 Ω in the high signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 4 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the high signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 2 - 4 V

4. Test or replace the B68 Knock Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Knock Sensor Replacement (Position 2) or Knock Sensor Replacement (Position 1)
• Control Module References for engine control module replacement, programming, and setup.

DTC P0335 or P0336

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0335

Crankshaft Position Sensor Circuit

DTC P0336

Crankshaft Position Sensor Performance

Diagnostic Fault Information

Circuit/System Description

The crankshaft position sensor circuits consist of an engine control module (ECM) supplied 5 V reference circuit, low reference circuit, and an output signal circuit. The crankshaft position sensor is an internally magnetic biased digital output integrated circuit sensing device. The sensor detects magnetic flux changes of the teeth and slots of a 58-tooth reluctor wheel on the crankshaft. Each tooth on the reluctor wheel is spaced at 60-tooth spacing, with 2 missing teeth for the reference gap. The crankshaft position sensor produces an ON/OFF DC voltage of varying frequency, with 58 output pulses per crankshaft revolution. The frequency of the crankshaft position sensor output depends on the velocity of the crankshaft. The crankshaft position sensor sends a digital signal, which represents an image of the crankshaft reluctor wheel, to the ECM as each tooth on the wheel rotates past the crankshaft position sensor. The ECM uses each crankshaft position signal pulse to determine crankshaft speed and decodes the crankshaft reluctor wheel reference gap to identify crankshaft position. This information is then used to determine the optimum ignition and injection points of the engine. The ECM also uses crankshaft position sensor output information to determine the camshaft relative position to the crankshaft, to control camshaft phasing, and to detect cylinder misfire.

Conditions for Running the DTC

P0335 Condition 1

• DTCs P0101, P0102 and P0103 are not set.

  OR

• The starter is engaged and the engine control module detects camshaft position sensor pulses.

  AND

• The airflow into the engine is greater than 1.5 g/s.

Condition 2

• The engine is running.
• The starter is not engaged.

Condition 3

• DTCs P0365 or P0366 are not set.
• The engine is running or the starter is engaged.

P0336 Condition 1

• DTCs P0335 is not set.
• The airflow into the engine is greater than 1.5 g/s.
• Engine speed is greater than 450 RPM.

Condition 2

• The engine is running.
• The starter is not engaged.

Condition 3

• DTCs P0101, P0102, and P0103 are not set.
• The airflow into the engine is greater than 1.5 g/s.

  OR

• The starter is engaged and the engine control module detects camshaft position sensor pulses.

Condition 4

• DTCs P0365 or P0366 are not set.
• The engine is running or the starter is engaged.

The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0335 Condition 1

The ECM does not detect a crankshaft position sensor pulse for greater than 4 s.

Condition 2

The ECM does not detect a crankshaft position sensor pulse for greater than 0.3 s.

Condition 3

The ECM does not detect a crankshaft position sensor pulse for 2 out of 10 engine revolutions.

P0336 Condition 1

The ECM detects that 10 or more crankshaft re-synchronizations have occurred within 10 s.

Condition 2

The ECM does not detect the synchronization gap on the reluctor wheel for greater than 0.4 s.

Condition 3

The ECM does not detect the synchronization gap on the reluctor wheel for 1.5 s after the starter was engaged.

Condition 4

The ECM detects less than 51 or greater than 65 crankshaft position sensor pulses during 1 engine revolution for 8 out of 10 engine revolutions.

Action Taken When the DTC Sets

• DTCs P0335 and P0336 are Type B DTCs.
• The camshaft position sensor is used to determine engine position.
• The camshaft actuators are commanded to the parked position.

Conditions for Clearing the DTC

DTCs P0335 and P0336 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Electronic Ignition System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0651 is not set.

• If the DTC is set

Refer to DTC P0641, P0651, P0697, P06A3, or P06D2.

• Go to next step: If the DTC is not set

3. Engine Running.

4. Verify the scan tool Crankshaft Position Active Counter parameter increments.

• If the counter does not increment

Refer to Circuit/System Testing.

• Go to next step: If the counter increments

5. Verify the scan tool Crankshaft Position Resync Counter parameter displays 0 counts and the engine does not stumble or stall while moving the related harness/connectors of the B26 Crankshaft Position Sensor.

• If greater than 0 counts and the engine stumbles or stalls

Refer to Circuit/System Testing.

• Go to next step: If 0 counts and the engine does not stumble or stall

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B26 Crankshaft Position Sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If 2 Ω or less, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 1 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Test for 4.8 - 5.2 V between the signal circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Ignition OFF, connect a 3 A fused jumper wire to the signal circuit terminal 3, ignition ON.

NOTE: Additional DTCs may set when performing this test.

7. Verify the scan tool Crankshaft Position Sensor Active Counter parameter increments while rapidly tapping the fused jumper wire end to ground.

• If the counter does not increment

Replace the K20 Engine Control Module.

• Go to next step: If the counter increments

8. Verify DTC P0336 is not set.

• If the DTC is set

Inspect for the conditions listed below:

• Excessive play or looseness of the B26 Crankshaft Position Sensor or the reluctor wheel
• Improper installation of the B26 Crankshaft Position Sensor
• Foreign material passing between the B26 Crankshaft Position Sensor and the reluctor wheel
• Damaged reluctor wheel
• Excessive air gap between the B26 Crankshaft Position Sensor and the reluctor wheel
• Engine oil for debris
• Timing chain, tensioner, and sprockets for wear or damage
  • If any of the conditions above are found, repair as necessary.
  • If all components test normal, test or replace the B26 Crankshaft Position Sensor.
• Go to next step: If the DTC is not set

9. Test or replace the B26 Crankshaft Position Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Crankshaft Position Sensor Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0340, P0341, P0365, or P0366

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0340

Intake Camshaft Position Sensor Circuit

DTC P0341

Intake Camshaft Position Sensor Performance

DTC P0365

Exhaust Camshaft Position Sensor Circuit

DTC P0366

Exhaust Camshaft Position System Performance

Diagnostic Fault Information

Circuit/System Description

For an overview of the component/system, refer to: Electronic Ignition System Description

The ECM uses information from the crankshaft position sensor and the camshaft position sensor(s) for sequencing and timing of the spark events.

Conditions for Running the DTC

P0340, P0365Condition 1

• DTC P0101, P0102, P0103 = Not set
• MAF Sensor=Greater than 1.5 g/s

Condition 2

• M64 Starter Motor=Active
• Camshaft Position Sensor=Signal received

Condition 3

• Engine=Running
• M64 Starter Motor=Inactive

Condition 4

• DTC P0335, P0336, P0641, P0651 = Not set
• Crankshaft=Synchronized
• M64 Starter Motor=Active

Condition 5

• DTC P0335, P0336, P0641, P0651 = Not set
• Crankshaft=Synchronized

Frequency the DTC runs=Continuously - After the running conditions are met.

P0341, P0366Condition 1

• DTC P0335, P0336, P0641, P0651 = Not set
• Crankshaft=Synchronized
• M64 Starter Motor=Active

Condition 2

• DTC P0335, P0336, P0641, P0651 = Not set
• Crankshaft=Synchronized

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

P0340, P0365Condition 1

Camshaft Position Sensor=No Signal - For greater than 5.5 s

Condition 2

Camshaft Position Sensor=No Signal - For greater than 4 s - Starter is engaged.

Condition 3

Camshaft Position Sensor=Less than 4 pulses - For greater than 3 s

Condition 4

Camshaft Position Sensor=No Signal - During the first 2 engine revolutions.

Condition 5

Camshaft Position Sensor=No Signal - During 200 engine revolutions.

P0341, P0366Condition 1

Camshaft Position Sensor=Less than 4 pulses - During 2 engine revolutions.

Condition 2

Camshaft Position Sensor=Greater than 6 pulses - During 2 engine revolutions.

Condition 3

Camshaft Position Sensor=Less than 398 pulses - Greater than 402 pulses - During 200 engine revolutions.

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type B DTC

• Camshaft Position Actuator=Park position
• Control module command=Reduced Engine Power

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type B DTC

Diagnostic Aids

The cranking period may take longer.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode.

2. Verify DTC P0641 is not set.

• If the DTC is set

Refer to:DTC P0641, P0651, P0697, P06A3, or P06D2

• Go to next step: If the DTC is not set

3. Engine - Running.

4. Verify DTC P0341, P0366 is not set.

• If the DTC is set

Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set

5. Verify the scan tool parameter:

• Exhaust Camshaft Position Active Counter=Increments
• Intake Camshaft Position Active Counter=Increments
• If the parameter value does not increment

Refer to: Circuit/System Testing

• Go to next step: If the parameter value increments

6. Verify the scan tool parameter: Exhaust Camshaft Position Active Counter or Intake Camshaft Position Active Counter=Increments

Perform the action while monitoring the parameter:

• Wiggle the harness and connector:B23 Camshaft Position Sensor
• Wiggle the harness and connector:K20 Engine Control Module
• If the parameter value does not increment

Repair as necessary - Wiring / Terminal(s) / Electrical Connector(s)

• Go to next step: If the parameter value increments

7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set

8. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the appropriate electrical connector: B23 Camshaft Position Sensor.

3. Test for less than 10 ohms between the test points: Low Reference circuit terminal 2 & Ground.

• If 10 ohms or greater

1. Disconnect the appropriate electrical connector: K20 Engine Control Module
2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 2@Component harness & The other end of the circuit @Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component:K20 Engine Control Module

• Go to next step: If less than 10 ohms

4. Ignition - On / Vehicle - In Service Mode.

5. Test for 4.8 to 5.2 V between the test points: 5 V Reference circuit terminal 1 & Ground.

• If less than 4.8 V

1. Ignition/Vehicle - Off
2. Disconnect the electrical connector:K20 Engine Control Module
3. Test for infinite resistance between the test points: 5 V Reference circuit terminal 1@ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: 5 V Reference circuit terminal 1@ Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component:K20 Engine Control Module

•  If greater than 5.2 V

1. Ignition/Vehicle - Off
2. Disconnect the electrical connector:K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points:5 V Reference circuit terminal 1@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component:K20 Engine Control Module

• Go to next step: If between 4.8 and 5.2 V

6. Test for 4.8 to 5.2 V between the test points: Signal circuit terminal 3 & Ground

• If less than 4.8 V

1. Ignition/Vehicle - Off
2. Disconnect the electrical connector:K20 Engine Control Module
3. Test for infinite resistance between the test points: Signal circuit terminal 3@ Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
4. Test for less than 2 ohms between the test points: Signal circuit terminal 3@ Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component:K20 Engine Control Module

• If greater than 5.2 V

1. Ignition/Vehicle - Off
2. Disconnect the electrical connector:K20 Engine Control Module
3. Ignition - On / Vehicle - In Service Mode
4. Test for less than 1 V between the test points: Signal circuit terminal 3@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component:K20 Engine Control Module

• Go to next step: If between 4.8 and 5.2 V

7. Verify DTC P0341, P0366 is not set.

• If the DTC is set

Verify the following conditions do not exist:

• B23 Camshaft Position Sensor & Reluctor Ring - Excessive play/Foreign material passing between the components/Incorrect air gap /Incorrect installation/Loose/Visible Damage
• Engine Oil - Contaminated/Dirty
• Timing Chain or Timing Belt - Visible Damage /Worn
• Timing Chain Tensioner or Timing Belt Tensioner - Visible Damage /Worn
  • If a condition exists - Repair or replace as necessary
  • If no condition exists - Test or replace the component:B23 Camshaft Position Sensor
• Go to next step: If the DTC is not set

8. Test or replace the component:B23 Camshaft Position Sensor

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Camshaft Position Sensor Replacement - Exhaust
• Camshaft Position Sensor Replacement - Intake
• For control module replacement, programming, and setup refer to: Control Module References

DTC P034A OR P034B

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis:Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P034A

Crankshaft Position Sensor - Engine Start Position Incorrect

DTC P034B

Crankshaft Position Sensor - Crankshaft Direction Incorrect

Circuit/System Description

The engine control module monitors the speed and the direction of rotation of the crankshaft during an autostop event and memorizes the crankshaft angle at which the engine stopped to be able to start the engine quicker.

Conditions for Running the DTC

P034A

• DTC P0335, P0336, P0651 = Not set
• Engine=Running - After an autostop event.
• Crankshaft position is being verified.

Frequency the DTC runs=Continuously - After the running conditions are met

P034B

• DTC P0335, P0336, P0651 = Not set
• Engine Speed=400 to 2, 000 RPM
• MAF Sensor=Greater than 1.5 g/s
• Crankshaft Position Sensor=Signal received

Frequency the DTC runs=Continuously - After the running conditions are met - For greater than 4 s

Conditions for Setting the DTC

P034A Condition 1

The difference between the memorized and actual crankshaft position was greater than 2 reluctor ring teeth during 2 autostart events in one ignition cycle.

Condition 2

The difference between the memorized and actual crankshaft position was greater than 1 reluctor ring teeth during 4 autostart events in one ignition cycle.

P034B

The direction of rotation of the crankshaft has changed more than 3 times within 10 s.

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type B DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type B DTC

Diagnostic Aids

A DTC may set depending on certain driving conditions and would not require a component replacement. The Circuit/System Verification must be performed.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode 2. Verify DTC P0335, P0336, P0651 is not set.

• If any of the DTCs are set

Refer to:Diagnostic Trouble Code (DTC) List - Vehicle

• Go to next step: If none of the DTCs are set

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Test or replace the component:B26 Crankshaft Position Sensor

• Go to next step: If the DTC is not set

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

Crankshaft Position Sensor Replacement

DTC P0351-P0354, P2300, P2301, P2303, P2304, P2306, P2307, P2309, or P2310

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P0351

Ignition Coil 1 Control Circuit

DTC P0352

Ignition Coil 2 Control Circuit

DTC P0353

Ignition Coil 3 Control Circuit

DTC P0354

Ignition Coil 4 Control Circuit

DTC P2300

Ignition Coil 1 Control Circuit Low Voltage

DTC P2301

Ignition Coil 1 Control Circuit High Voltage

DTC P2303

Ignition Coil 2 Control Circuit Low Voltage

DTC P2304

Ignition Coil 2 Control Circuit High Voltage

DTC P2306

Ignition Coil 3 Control Circuit Low Voltage

DTC P2307

Ignition Coil 3 Control Circuit High Voltage

DTC P2309

Ignition Coil 4 Control Circuit Low Voltage

DTC P2310

Ignition Coil 4 Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

For an overview of the component/system, refer to:Electronic Ignition System Description

The ECM controls the spark event for each cylinder through individual ignition coil control circuits.

When the ECM commands the ignition control circuit On, electrical current flows through the primary winding of the ignition coil, creating a magnetic field. When a spark event is requested, the ECM commands the ignition control circuit Off, interrupting current flow through the primary winding. The collapsing magnetic field created by the primary winding induces a high voltage in the secondary winding, which is connected to the spark plugs.

Conditions for Running the DTC

• Engine=Running
• Ignition Voltage=Greater than 11 V

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

Control Circuit=Commanded state does not match the actual state

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type A DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type A DTC

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index and Inline Harness Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Special Tools

J-26792 Ignition Spark Tester

Equivalent regional tools: Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools)

Circuit/System Verification

1. Engine - Running.

2. Verify the scan tool parameter:

• Ignition Coil 1 - 4 Control Circuit High Voltage Test Status = OK or Not Run
• Ignition Coil 1 - 4 Control Circuit Low Voltage Test Status = OK or Not Run
• Ignition Coil 1 - 4 Control Circuit Open Test Status = OK or Not Run
• If not the specified state

Refer to: Circuit/System Testing

• Go to next step: If the specified state

3. Verify the scan tool parameter:

• Ignition Coil 1 - 4 Control Circuit High Voltage Test Status = OK or Not Run
• Ignition Coil 1 - 4 Control Circuit Low Voltage Test Status = OK or Not Run
• Ignition Coil 1 - 4 Control Circuit Open Test Status = OK or Not Run
• Perform the action while monitoring the parameter:
• Wiggle the harness and connector:T8 Ignition Coil
• Wiggle the harness and connector:K20 Engine Control Module
• If not the specified state

Repair as necessary - Wiring / Terminal(s) / Electrical Connector(s)

• Go to next step: If the specified state

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to: Circuit/System Testing

• Go to next step: If the DTC is not set

5. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the appropriate electrical connector:T8 Ignition Coil.

3. Test for less than 10 ohms between the test points: Ground circuit terminal 1/A & Ground.

• If 10 ohms or greater

1. Disconnect the ground connection: Ground terminal
2. Test for less than 2 ohms between the test points: Ground circuit terminal 1/A@Component harness & The other end of the circuit @Ground terminal
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Repair the open/high resistance in the ground connection.

• Go to next step: If less than 10 ohms

4. Ignition - On / Vehicle - In Service Mode.

5. Verify a test lamp does not turn On between the test points: Control circuit terminal 3/C & B+.

• If the test lamp turns On

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for infinite resistance between the test points: Control circuit terminal 3/C@Component harness & Ground
   • If less than infinite resistance - Repair the short to ground on the circuit.
   • If infinite resistance - Replace the component: K20 Engine Control Module

• Go to next step: If the test lamp does not turn On

6. Remove - Test Lamp.

7. Engine - Running.

8. Verify the scan tool parameter: Ignition Coil 1 - 4 Control Circuit High Voltage Test Status = OK or Not Run.

• If not the specified state

1. Ignition/Vehicle - Off
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for less than 1 V between the test points:Control circuit terminal 3/C@Component harness & Ground
   • If 1 V or greater - Repair the short to voltage on the circuit.
   • If less than 1 V - Replace the component: K20 Engine Control Module

• Go to next step: If the specified state

9. Ignition/Vehicle - Off.

10. Connect a 3 A fused jumper wire between the test points:Control circuit terminal 3/C & Ignition circuit terminal 4/D.

11. Engine - Running.

12. Verify the scan tool parameter: Ignition Coil 1 - 4 Control Circuit High Voltage Test Status = OK or Not Run.

• If not the specified state

1. Ignition/Vehicle - Off & Remove - Jumper wire(s)
2. Disconnect the electrical connector: K20 Engine Control Module
3. Test for less than 2 ohms between the test points: Control circuit terminal 3/C@Component harness & The other end of the circuit@Control module harness
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component: K20 Engine Control Module

• Go to next step: If the specified state

13. Test or replace the component:T8 Ignition Coil.

Component Testing

NOTE: Circuit/System Testing must be performed before proceeding with Component Testing.

1. Ignition/Vehicle - Off.

2. Remove the appropriate component:T8 Ignition Coil - Leave the electrical connector connected.

3. Install the special tool: J-26792 Ignition Spark Tester.

4. Engine - Running.

NOTE: An erratic or weak spark is considered a no spark condition.

5. Verify there is spark at the tool.

• If there is no spark

Replace the component:T8 Ignition Coil

• Go to next step: If there is spark

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Ignition Coil Replacement
• For control module replacement, programming, and setup refer to: Control Module References

DTC P0420

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0420

Catalyst System Low Efficiency

Circuit/System Description

The catalyst within the converter promotes a chemical reaction, which oxidizes the hydrocarbons and the CO that are present in the exhaust gas. This process converts the hydrocarbons and the CO into water vapor and carbon dioxide (CO2), and reduces the NOx, converting the NOx into nitrogen. The catalyst also stores oxygen. The engine control module (ECM) monitors this process by using heated oxygen sensors (HO2S) that are in the exhaust stream before and after the 3- way catalyst. The HO2S produces an output signal that the ECM uses to calculate the oxygen storage capacity of the catalyst.

This indicates the ability of the catalyst to convert the exhaust emissions efficiently. The ECM monitors the efficiency of the catalyst by monitoring the HO2S during an off-idle, decel fuel cut off (DFCO) event. When the catalyst is functioning properly, the post catalyst HO2S response to the fuel conditions during the DFCO event is slow compared to the response of the pre catalyst HO2S. When the post HO2S response is near that of the pre HO2S, the oxygen storage capability and efficiency of the catalyst may be degraded below an acceptable threshold.

Conditions for Running the DTC

• DTC P0030, P0031, P0032, P0036, P0037, P0038, P0053, P0054, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P0131, P0132, P0133, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0141, P015A, P015B, P0171, P0172, P0201, P0202, P0203, P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P1248, P1249, P124A, P124B, P16F3, P2101, P2135, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157, P2270, or P2271 is not set.
• The engine speed is between 950 - 2, 950 RPM to enable the catalyst diagnostic. Once the engine speed is in range, the engine speed must be between 900 - 3, 050 RPM to keep the test enabled.
• Accelerator pedal position is at most 4 %.
• Ethanol estimation is not active.
• Evaporative emission (EVAP) purge is not active.
• Post HO2S heater is ON for greater than 180 s.
• Mass air flow (MAF) is between 2 - 13 g/s.
• System voltage is between 10 - 32 V.
• Vehicle speed is between 64 - 126 km/h (40 - 78 MPH) to enable the catalyst diagnostic.
• To keep the test enabled the vehicle speed is between 56 - 132 km/h (35 - 82 MPH).
• Catalyst calculated temperature is between 500 - 900ºC (932 - 1, 652ºF).
• Engine is operating in closed loop.
• Engine is operating in DFCO.

This diagnostic attempts one test during each valid OFF-idle period once the above conditions have been met. This diagnostic attempts up to 4 tests during each drive cycle.

Conditions for Setting the DTC

The ECM determines that the efficiency of the catalyst has degraded below a calibrated threshold.

Action Taken When the DTC Sets

DTC P0420 is a Type A DTC.

Conditions for Clearing the DTC

DTC P0420 is a Type A DTC.

Diagnostic Aids

Inspect for the following conditions, which may cause a catalytic converter to degrade:

• Engine misfire
• High engine oil or high coolant consumption
• Retarded spark timing
• Weak or poor spark
• Lean fuel mixture
• Rich fuel mixture
• Damaged oxygen sensor or wiring harness

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition On.

2. Verify there are no other DTCs set.

• If other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If no other DTCs are set

3. Operate the vehicle within the Conditions for Running the DTC.

4. Verify the scan tool Catalyst Monitor Not At Idle Test Conditions Met parameter changes to Yes.

• If Yes is not displayed

Refer to step 3.

• Go to next step: If Yes is displayed

5. Verify the Catalyst Monitor Test Result parameter displays Passed when performing the steps listed below:

1. Monitor the scan tool Catalyst Monitor Test State parameter. When the parameter indicates Active, the Catalyst Monitor Test is running.

NOTE: When the test has completed, the Catalyst Monitor Test Counter will increment by one and the Catalyst Monitor Test Result will indicate Passed, Failed or No Result.

2. Continue to monitor the parameter. When the parameter indicates Inactive, the Catalyst Monitor Test has completed.
3. Verify the scan tool Catalyst Monitor Test Result displays Passed.

• If No Result is displayed

Repeat steps 3 - 5 until the Test Result parameter indicates Passed or Failed

• If Failed is displayed

Refer to Circuit /System Testing

• Go to next step: If Passed is displayed

6. All OK.

Circuit/System Testing

1. Verify the conditions listed below do not exist with the catalytic converter:

• Dents
• Severe discoloration caused by excessive temperatures
• Road damage
• Internal rattles caused by damaged catalyst substrate
• Restrictions
  • If a condition is found

    Replace the catalytic converter.

  • Go to next step: If no condition is found

2. Verify the conditions listed below do not exist with the exhaust system:

• Leaks
• Restrictions
• Physical damage
• Loose or missing hardware
  • If a condition is found

    Repair or replace the component as necessary.

  • Go to next step: If no condition is found

3. Verify the conditions listed below do not exist with the B52B Heated Oxygen Sensor 2:

• Incorrect torque
• Damage
  • If a condition is found

    Replace the B52B Heated Oxygen Sensor 2 or repair the condition as necessary.

  • Go to next step: If no condition is found

4. Replace the catalytic converter.

Repair Instructions

• Warm Up Three-Way Catalytic Converter Replacement (2.0L LTG)
• Exhaust Leakage
• Heated Oxygen Sensor Replacement - Sensor 2
• Perform the HO2S Heater Learn procedure with a scan tool after replacing a heated oxygen sensor.
• Restricted Exhaust

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Turn Off the ignition for 60 s.

5. Operate the vehicle within the Conditions for Running the DTC.

6. Verify the scan tool Catalyst Monitor Not At Idle Test Conditions Met parameter changes to Yes.

• If Yes is not displayed

  Refer to step 5.

• Go to next step: If Yes is displayed

7. Verify the Catalyst Monitor Test Result displays Passed when performing the steps listed below:

1. Monitor the scan tool Catalyst Monitor Test State parameter. When the parameter indicates Active, the Catalyst Monitor Test is running.

NOTE: When the test has completed, the Catalyst Monitor Test Counter will increment by one and the Catalyst Monitor Test Result will indicate Passed, Failed or No Result.

2. Continue to monitor the parameter. When the parameter indicates Inactive, the Catalyst Monitor Test has completed.
3. Verify the scan tool Catalyst Monitor Test Result displays Passed.
   • If No Result is displayed

     Repeat steps 5 - 7 until the Test Result indicates Passed or Failed

   • If Failed is displayed

     Refer to Circuit /System Testing

   • Go to next step: If Passed is displayed

8. All OK.

DTC P0442

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0442

Evaporative Emission (EVAP) System Small Leak Detected

Circuit/System Description

The engine off natural vacuum (EONV) test is the small leak detection diagnostic for the evaporative emission (EVAP) system. This diagnostic tests the EVAP system for a small leak when the key is turned OFF and the correct conditions are met. Heat from the exhaust system is transferred into the fuel tank while the vehicle is operating. When the vehicle is turned OFF and the EVAP system is sealed a change in the fuel tank vapor temperature occurs which results in a corresponding pressure change in the fuel tank vapor space. This change is monitored by the engine control module (ECM) using the fuel tank pressure (FTP) sensor input. With a leak in the system, the amount of pressure change will be less than that of a sealed system.

Conditions for Running the DTC

• DTCs P010B, P012B, P012C, P012D, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P0222, P0223, P0236, P0237, P0238, P0443, P0446, P0449, P0452, P0453, P0455, P0458, P0459, P0461, P0462, P0463, P0496, P0498, P0499, P0502, P0503, P0722, P0723, P111E, P117D, P017C, P017D, P017B, P117B, P117F, P117E, P117C, P2066, P2067, P2068, P1221, P222B, P222C, P222D, P222E, P262B. are not set.
• The barometric pressure (BARO) is greater than 70 kPa.
• The engine coolant sensor (ECT) is greater than 63ºC (145ºF)
• The fuel level is between 10 - 90%.
• The start-up engine coolant temperature (ECT) and the start-up intake air temperature (IAT) are within 8ºC (14ºF).
• The engine run time before shut-off was greater than 10 min.
• The drive distance before engine shut-off was greater than 5 km (3 mi).
• The ambient air temperature at the end of the drive cycle is between 0 - 34ºC (32 - 93ºF).
• DTC P0442 runs once per drive cycle during the hot soak period after the ignition is turned OFF and may require up to 40 min to complete. The control module will not make more than 2 test attempts per day. The time since the last completed engine off natural vacuum test must be at least 17 h if passed or 10 h if failed.

Conditions for Setting the DTC

• The ECM detects a leak in the EVAP system that is greater than a calibrated amount.
• The ECM must complete several engine off natural vacuum tests before the diagnostic can turn the MIL ON or OFF.

Action Taken When the DTC Sets

DTC P0442 is a Type A DTC.

Conditions for Clearing the DTC

DTC P0442 is a Type A DTC.

Diagnostic Aids

• The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. When injecting smoke at the service port tool temporarily leave the EVAP Vent Solenoid Valve open until smoke is observed then close the system and continue testing.
• To help locate intermittent leaks using the GE 41413-A , move all EVAP components while observing smoke with the GE 41413-SPT.
• Individual components can be isolated and tested using adapters in the GE 41413-300.
• When servicing the EVAP system, test pressure must not exceed 13 in H20 (0.5 PSI) as pressure in excess of this could cause system components to perform inaccurately.
• A condition may exist where a leak in the EVAP system only exists under a vacuum condition.
• This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the FTP Sensor parameter for vacuum decay.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

• CH 48096 EVAP Service Port Access Tool
• GE 41413 - A Evaporative Emissions System Tester (EEST)
• GE 41413 - 300 EVAP Cap and Plug Kit
• GE 41413 - SPT High Intensity White Light

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Testing

NOTE:

• Refer to the GE 41413-A detailed instructions in Evaporative Emission System Diagnosis.
• Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize or produce smoke from a leak.
• Ensure that the underbody temperature of the vehicle and the tester are similar.

1. Disconnect the purge tube at the quick connector on the EVAP canister side of the Q12 Evaporative Emission Canister Purge Solenoid Valve and install the CH 48096.

2. Connect the GE 41413-A to the CH 48096.

3. Command the EVAP Purge/Seal function to Not Venting or System Seal with a scan tool to seal the EVAP system.

4. Use the flow meter on the GE 41413-A calibrated to 0.51 mm (0.020 in) to determine if there is a leak.

• If a leak is detected

1. Use the GE 41413-A to apply smoke to the EVAP system at the purge tube service port until the leak is located using the GE 41413-SPT.
   • If leak is detected, repair or replace the affected component as necessary.

• Go to next step: If no leak is detected

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

DTC P0443, P0458, or P0459

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0443

Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit

DTC P0458

Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit Low Voltage

DTC P0459

Evaporative Emission (EVAP) Purge Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The evaporative emission (EVAP) purge solenoid valve is used to purge fuel vapor from the EVAP canister to the intake manifold. The EVAP purge solenoid valve is pulse width modulated (PWM).

Ignition voltage is supplied directly to the EVAP purge solenoid valve. The engine control module (ECM) controls the solenoid valve by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage. A scan tool will display the amount of ON time as a percentage.

Conditions for Running the DTC

• The ignition voltage is greater than 11 V.
• The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0443

The ECM detects the EVAP Purge Solenoid Valve control circuit is open for greater than 0.25 s.

P0458

The ECM detects the EVAP Purge Solenoid Valve control circuit is shorted to ground for greater than 0.25 s.

P0459

The ECM detects the EVAP Purge Solenoid Valve control circuit is shorted to voltage for greater than 0.25 s.

Action Taken When the DTC Sets

DTC P0443, P0458 and P0459 are Type B DTCs.

Conditions for Clearing the DTC

DTC P0443, P0458 and P0459 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: The audible clicking intensity will vary depending on mounting locations and interference with the fuel injectors clicking. You may also feel a change in the frequency of clicking.

1. Ignition ON, verify DTC P0690 is not set.

• If the DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If the DTC is not set

2. Command the EVAP Purge Solenoid Valve from 0 to 50% and back to 0% with a scan tool while observing the following control circuit status parameters:

• EVAP Purge Solenoid Valve Control Circuit Open Test Status
• EVAP Purge Solenoid Valve Control Circuit Low Voltage Test Status
• EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing

• Go to next step: If Malfunction is not displayed

3. Verify the EVAP Purge Solenoid Valve control circuit parameters above do not display Malfunction when moving the related harnesses and connectors of the Q12 Evaporative Emission Purge Solenoid Valve.

• If Malfunction is displayed

Refer to Circuit/System Testing

• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve. Ignition ON, 2. Verify that a test lamp illuminates between the ignition voltage circuit terminal A or 1 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp and disconnect any component connected to the ignition circuit.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp.
2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition voltage circuit for a short and replace as necessary.

• Go to next step: If the test lamp illuminates

3. Verify that a test lamp does not illuminate between the ignition circuit terminal A or 1 and the control circuit terminal B or 2.

• If the test lamp illuminates

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status parameter is OK when commanding the EVAP Purge Solenoid Valve to 50% with a scan tool.

• If OK is not displayed

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, Ignition ON.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal B or 2 and the ignition circuit terminal A or 1.

7. Verify the scan tool EVAP Purge Solenoid Valve Control Circuit High Voltage Test Status parameter is Malfunction when commanding the EVAP Purge Solenoid Valve to 50% with a scan tool.

• If Malfunction is not displayed

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If Malfunction is displayed

8. Test or replace the Q12 Evaporative Emission Purge Solenoid Valve.

Component Testing

Static Test

1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.

2. Test for 10-30 Ω between the control terminal B or 2 and the ignition circuit terminal A or 1.

• If not between 10-30 Ω

Replace the Q12 Evaporative Emission Purge Solenoid Valve.

• Go to next step: If between 10-30 Ω

3. All OK.

Dynamic Test

1. Ignition OFF, disconnect the harness connector at the Q12 Evaporative Emission Purge Solenoid Valve.

2. Install a 3 A fused jumper wire between the ignition, terminal A or 1 and 12 V. Install a jumper wire between the control terminal B or 2 and ground.

3. Verify the Evaporative Emission Purge Solenoid Valve turns on & off/clicks and flows vacuum.

• If it does not turn on & off/click or flow vacuum.

Replace the Q12 Evaporative Emission Purge Solenoid Valve.

• Go to next step: If it does turn on & off/clicks and flows vacuum.

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Evaporative Emission Canister Purge Solenoid Valve Replacement
• Control Module References for control module replacement, programming and setup

DTC P0446

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0446

Evaporative Emission (EVAP) Vent System Performance

Typical Scan Tool Data

Circuit/System Description

This DTC tests the evaporative emission (EVAP) system for a restricted or blocked EVAP vent path.

There are two parts to this test.

• Part one uses the fuel tank pressure sensor to indicate vacuum comes within a calibrated value.
• The second part of this test looks for excessive vacuum which would indicate a restriction. The duration of this second part of is a function of purge volume through the system.

The table listed below illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP purge and vent solenoid valves.

Conditions for Running the DTC

• DTCs P00C8, P00C9, P00CA, P0068, P0090, P0091, P0092, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P012B, P012C, P012D, P017B, P017C, P017D, P0222, P0223, P0443, P0449, P0452, P0453, P0454, P0458, P0459, P0498, P0499, P0502, P0503, P0606, P0722, P0723, P0191, P0192, P0193, P06A3, P06DB, P06DE, P0A1D, P0601, P0604, P0697, P111E, P160D, P160E, P1682, P16A0, P16A1, P16A2, P16F3, P1104, P117B, P117C, P117D, P117E, P117F, P127A, P127C, P127D, P15F2, P1221, P2100, P2101, P2102, P2103, P2122, P2123, P2127, P2128, P2135, P2138, P215B, P2176, P2227, P2228, P2229, P2230, P228C, P228D, U0073, U0074, U0293, U1817 are not set.
• The ignition voltage is between 11 - 32 V.
• The barometric pressure (BARO) is greater than 70 kPa.
• The fuel level is between 10 - 90%.
• The startup engine coolant temperature (ECT) is less than 35ºC (95ºF).
• The startup intake air temperature (IAT) is between 4 - 34ºC (39 - 95ºF).
• DTC P0446 runs once per cold start.

Conditions for Setting the DTC

NOTE: There are two stages to setting this DTC. Stage one, prep test, then stage two test.

• If fuel tank pressure sensor reading is greater than 0.62 kPa (2.5 in H2O) of pressure or less than 1.24 kPa (5 in H2O) of vacuum for 60 s.

  OR

• If fuel tank pressure sensor reading is less than 2.98 kPa (12 in H2O) of vacuum for 5 s before 10 L (2.6 gal) of purge volume has passed through the system.
• After setting the DTC for the first time, 2 L (0.5 gal) of fuel must be consumed before setting the DTC for the second time.

Action Taken When the DTC Sets

DTC P0446 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0446 is a Type B DTC.

Diagnostic Aids

An intermittent condition could be caused by:

• A damaged EVAP vent housing
• A temporary blockage at the EVAP vent solenoid valve inlet
• Pinched vent hose

A blockage in the vent system may also cause a poor fuel fill problem.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

• CH 41415-30 Fuel Tank Cap Adapter
• GE 41413-A Evaporative Emissions System Tester (EEST)

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0443 is not set.

• If the DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If the DTC is not set

3. Ignition OFF, remove the fuel tank filler cap. Ignition ON.

4. Verify the scan tool Fuel Tank Pressure Sensor parameter is between 1.3 - 1.7 V.

• If not between the 1.3 - 1.7 V

Refer to P0452, P0453 within DTC P0451-P0454.

• Go to next step: If between the 1.3 - 1.7 V

5. Install the fuel tank filler cap. Engine idling at operating temperature for 5 min.

6. Verify the scan tool Fuel Tank Pressure Sensor parameter does not increase to greater than 2.5 V when commanding the EVAP Purge Solenoid Valve to 50%.

• If greater than 2.5 V

Refer to Circuit/System Testing.

• Go to next step: If 2.5 V or less

7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK.

Circuit/System Testing

NOTE: Perform the Circuit/System Verification before proceeding with the Circuit/System Testing.

1. Test for a blockage or restrictions in the EVAP system components listed below and repair as necessary.

• Evaporative Emission Vent System Hoses
• Evaporative Emission Canister
• Q13 Evaporative Emission Vent Solenoid Valve
• Evaporative Emission Vent Filter

2. Reconnect all previously disconnected EVAP hardware.

NOTE: Refer to the GE 41413-A detailed instructions in Evaporative Emission System Diagnosis.

3. Remove the fuel fill cap and connect the CH 41415-30 to the fuel tank filler neck. Connect the GE 41413-A to the CH 41415-30.

4. Command the EVAP Purge/Seal function to System Seal with a scan tool to seal the EVAP system.

5. Turn the nitrogen/smoke valve on the GE 41413-A to nitrogen.

NOTE: DO NOT exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.

6. Use the remote switch to activate the GE 41413-A and pressurize the fuel tank to 1.24 kPa (5.0 in H2O).

7. Verify the scan tool Fuel Tank Pressure Sensor parameter is 0 kPa (0 in H2O) when commanding the EVAP Vent Solenoid Valve to OFF.

• If not 0 in H20

Test for a blockage or a restriction in the EVAP vent hose or inlet. If the inlet or hose test normal, replace the Q13 Evaporative Emission Vent Solenoid Valve.

• Go to next step: If 0 in H2O

8. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to step 1 above.

• Go to next step: If the DTC does not set

9. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Evaporative Emission Canister Solenoid Replacement (FWD) or Evaporative Emission Canister Solenoid Replacement (AWD) for EVAP Vent Solenoid Valve replacement
• Evaporative Emission Canister Replacement (AWD) or Evaporative Emission Canister Replacement (FWD)
• Fuel Tank Pressure Sensor Replacement (FWD) or Fuel Tank Pressure Sensor Replacement (AWD)

DTC P0449, P0498, or P0499

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0449

Evaporative Emission (EVAP) Vent Solenoid Valve Control Circuit

DTC P0498

Evaporative Emission (EVAP) Vent Solenoid Valve Control Circuit Low Voltage

DTC P0499

Evaporative Emission (EVAP) Vent Solenoid Valve Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The evaporative emission (EVAP) vent solenoid valve is a normally open valve. Battery voltage is supplied to the EVAP vent solenoid valve through a fuse. The engine control module (ECM) grounds the EVAP vent solenoid valve control circuit through an internal switch called a driver. The evaporative emission (EVAP) vent solenoid valve is a normally open valve. Battery voltage is supplied to the EVAP vent solenoid valve through a fuse. A scan tool will display the commanded state of the EVAP vent solenoid valve as ON (Not Venting) or OFF (Venting).

Conditions for Running the DTC

• The system voltage is greater than 11 V.
• The DTCs run continuously once the above conditions are met.

Conditions for Setting the DTC

P0449

The ECM detects the EVAP Vent Solenoid Valve control circuit is open for greater than 0.25 s.

P0498

The ECM detects the EVAP Vent Solenoid Valve control circuit is shorted to ground for greater than 0.25 s.

P0499

The ECM detects the EVAP Vent Solenoid Valve control circuit is shorted to voltage for greater than 0.25 s.

Action Taken When the DTC Sets

DTC P0449, P0498 and P0499 are Type B DTCs.

Conditions for Clearing the DTC

DTC P0449, P0498 and P0499 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: An audible click may be heard when performing step 2 below.

1. Ignition ON.

2. Command the EVAP Vent Solenoid Valve to ON (Not Venting) and OFF (Venting) with a scan tool while observing the following control circuit status parameters:

• EVAP Vent Solenoid Valve Control Circuit Open Test Status
• EVAP Vent Solenoid Valve Control Circuit Low Voltage Test Status
• EVAP Vent Solenoid Valve Control Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing

• Go to next step: If Malfunction is not displayed

3. Verify the EVAP Vent Solenoid Valve control circuit parameters above do not display Malfunction when moving the related harnesses and connectors of the Q13 Evaporative Emission Vent Solenoid Valve.

• If Malfunction is displayed

Refer to Circuit/System Testing

• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Q13 Evaporative Emission Vent Solenoid Valve, Ignition ON,

2. Verify that a test lamp illuminates between the B+ circuit terminal B or 2 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the B+ circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp.
2. Test for infinite resistance between the B+ circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the B+ circuit for a short and replace as necessary.

• Go to next step: If the test lamp illuminates

3. Verify that a test lamp does not illuminate between the B+ circuit terminal B or 2 and the control circuit terminal A or 1.

• If the test lamp illuminates

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool EVAP Vent Solenoid Valve Control Circuit High Voltage Test Status parameter is OK when commanding the EVAP Vent Solenoid Valve to ON (Not Venting) with a scan tool.

If OK is not displayed

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, Ignition ON.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal A or 1 and the B+ circuit terminal B or 2.

7. Verify the scan tool EVAP Vent Solenoid Valve Control Circuit High Voltage Test Status parameter is Malfunction when commanding the EVAP Vent Solenoid Valve to ON (Not Venting) with a scan tool.

• If Malfunction is not displayed

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If Malfunction is displayed

8. Test or replace the Q13 Evaporative Emission Vent Solenoid Valve.

Component Testing

1. Ignition OFF, disconnect the harness connector at the Q13 Evaporative Emission Vent Solenoid Valve.

2. Test for 10-30 Ω between the control terminal A or 1 and the B+ circuit terminal B or 2.

• If not between 10-30 Ω

Replace the Q13 Evaporative Emission Vent Solenoid Valve.

• Go to next step: If between 10-30 Ω

3. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Control Module References for ECM replacement, programming and setup.
• Evaporative Emission Canister Solenoid Replacement (FWD) or Evaporative Emission Canister Solenoid Replacement (AWD) for EVAP Vent Solenoid Valve replacement.

DTC P0451-P0454

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0451

Fuel Tank Pressure Sensor Performance

DTC P0452

Fuel Tank Pressure Sensor Circuit Low Voltage

DTC P0453

Fuel Tank Pressure Sensor Circuit High Voltage

DTC P0454

Fuel Tank Pressure Sensor Circuit Intermittent

Diagnostic Fault Information

Typical Scan Tool Data

Fuel Tank Pressure Sensor Voltage

Circuit/System Description

The fuel tank pressure sensor measures vapor pressure or vacuum in the evaporative emission (EVAP) system. The engine control module (ECM) supplies a 5 V reference and a low reference circuit to the fuel tank pressure sensor. The fuel tank pressure sensor signal voltage varies depending on EVAP system pressure or vacuum. The controller also uses this fuel tank pressure signal to determine atmospheric pressure for use in the engine-off small leak test, DTC P0442. Before using this signal as an atmospheric reference it must first be re-zeroed.

Conditions for Running the DTC

P0451

• DTC P0451 runs only when the engine-off natural vacuum small leak test, P0442, executes.
• The number of times this test runs can range from 0 - 2 per engine-off period. The length of the test can be up to 10 min.

P0452 and P0453

DTC P0452 and P0453 run continuously when the ignition is ON.

P0454

• DTC P0454 runs only when the engine-off natural vacuum small leak test, P0442, executes.
• This test can run once per engine-off period. The length of the test can be up to 10 min.
• A refueling event is not detected. A refueling event is confirmed if the fuel level has a persistent change of 10% for 30 s during a 10 min refueling rationality test.

Conditions for Setting the DTC

P0451

This DTC will set if the controller is unable to re-zero the fuel tank pressure sensor voltage within a calibrated range during the engine-off small leak test, P0442.

P0452

The fuel tank pressure sensor voltage is less than 0.15 V for greater than 10 s.

P0453

The fuel tank pressure sensor voltage is greater than 4.9 V for greater than 10 s.

P0454

If, during the engine-off natural vacuum small leak test, P0442, the ECM detects an abrupt fuel tank pressure signal change, other than a refueling event, this DTC will set. An abrupt change is defined as a change of greater than 0.45 in H2O (0.11 kPa) in the span of 1 s but less than 1 in H2O (0.25 kPa) in 12.5 ms. This test must fail twice to set this DTC.

Action Taken When the DTC Sets

• DTCs P0451 and P0454 are Type A DTCs.
• DTCs P0452 and P0453 are Type B DTCs.

Conditions for Clearing the MIL/DTC

• DTCs P0451 and P0454 are Type A DTCs.
• DTCs P0452 and P0453 are Type B DTCs.

Diagnostic Aids

P0451 and P0454

• A restriction in the EVAP canister or vent lines could prevent fuel vapor pressure from bleeding off fast enough. If the vent system cannot bleed off pressure fast enough, the re-zero procedure may not complete successfully, which could cause this DTC to set.
• Ensure that the reference port on the fuel tank pressure sensor is unobstructed.
• An fuel tank pressure sensor that is skewed or does not have a linear transition from low to high may cause this DTC to set. Scan tool control functions, snapshot, and plot functions can help detect erratic sensor response. To test the sensor signal under vacuum conditions, use the Quick Snapshot and the Purge/Seal functions to capture data while commanding purge to 20%, then plot the data to look for erratic sensor operation. A similar test can be done for the pressure side of the sensor operation by applying pressure with the GE-41413-A while taking a snapshot.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

GE-41413-A Evaporative Emission System Tester

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Remove the fuel cap.

2. Ignition ON, engine OFF.

3. Verify the scan tool Fuel Tank Pressure sensor parameter is between 1.3 and 1.7 V.

• If not between 1.3 - 1.7 V

Refer to Circuit/System Testing.

• Go to next step: If between 1.3 - 1.7 V

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition OFF, all vehicle systems OFF, this may take up to 2 min, for all vehicle systems to power down. Disconnect the harness connector at the B150 Fuel Tank Pressure Sensor.

2. Test for less than 5 Ω of resistance between the low reference circuit terminal 2 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool Fuel Tank Pressure parameter is less than 0.2 V.

• If 0.2 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON
2. Test for less than 1 V between the signal circuit terminal 1 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.2 V

6. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the 5 V reference circuit terminal 3.

7. Verify the scan tool Fuel Tank Pressure sensor parameter is greater than 4.7 V.

• If 4.7 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.7 V

8. Test or replace the B150 Fuel Tank Pressure Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Tank Pressure Sensor Replacement (FWD) or Fuel Tank Pressure Sensor Replacement (AWD)
• Control Module References for control module replacement, programming and setup

DTC P0455

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0455

Evaporative Emission (EVAP) System Large Leak Detected

Circuit/System Description

The engine control module (ECM) tests the evaporative emission (EVAP) system for a large leak or restrictions to the purge path in the EVAP system. When the enabling criteria has been met, the ECM commands the EVAP vent solenoid valve and purge solenoid valve ON, allowing vacuum into the EVAP system. The ECM monitors the fuel tank pressure sensor voltage to verify that the system is able to reach a predetermined level of vacuum within a set amount of time.

Conditions for Running the DTC

• DTCs P00C8, P00C9, P010C, P010D, P16A0, P16A1, P16A2, P160E, P160D, P16F3, P0068, P0101, P0102, P0103, P0111, P0112, P0113, P0114 P0116, P0117, P0118, P0122, P0123, P0125, P0128, P0191, P0192, P0193, P0222, P0223, P0443, P0449, P0452, P0453, P0454, P0502, P0503, P0601, P0604, P0606, P0722, P0723, P1104, P1682, P2100, P2101, P2102, P2103, P2135, P2176, P2227, P2228, P2229, P2230 are not set.
• The ignition voltage is between 11 - 32 V.
• The barometric pressure (BARO) is greater than 70 kPa.
• The fuel level is between 10 - 90%.
• The cold startup engine coolant temperature (ECT) and the startup intake air temperature (IAT) are within 8ºC (14ºF).
• The startup engine coolant temperature (ECT) is less than 35ºC (95ºF).
• The startup intake air temperature (IAT) is between 4 - 34ºC (39 - 93ºF).
• DTC P0455 runs once per cold start, shortly after purge is enabled followed by vent system performance test P0446.

Conditions for Setting the DTC

• The EVAP system is not able to achieve or maintain a calibrated level of vacuum before a calibrated amount of purge volume has passed through the system.
• After setting the DTC for the first time, 2 L (0.5 gal) of fuel must be consumed before setting the DTC for the second time.
• With a DTC P0455 detected a weak vacuum follow-up test (fuel cap replacement test) will run and pass if tank vacuum is greater than 2.74 kPa (11 in H2O). This test will run for a maximum of 21 min. This test runs until it passes.

Action Taken When the DTC Sets

DTC P0455 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0455 is a Type B DTC.

Diagnostic Aids

• Inspect for a loose, missing, damaged, or incorrect fuel fill cap.
• Inspect for a damaged fuel filler neck seal surface.
• A blockage or restriction in the EVAP purge solenoid valve, purge pipe, EVAP canister, or vapor pipe, can cause this DTC to set.
• The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. For example, when injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is observed, then close the system and continue testing. If using a fuel cap adapter at the filler neck, use the J- 41413-VLV at the service port to allow the system to fill faster.
• To help locate intermittent leaks using the GE-41413-A move all EVAP components while observing smoke with the GE-41413-SPT.
• Individual components can be isolated and tested using adapters in the J-41413-300.
• When servicing the EVAP system, test pressure must not exceed 13 in H20 (0.5 PSI) as pressure in excess of this could cause system components to perform inaccurately.
• A condition may exist where a leak in the EVAP system only exists under a vacuum condition.
• This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the Fuel Tank Pressure Sensor parameter for vacuum decay.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

• CH-48096 EVAP Service Access Port Tool
• GE-41413-A Evaporative Emissions System Tester
• GE-41413-SPT High Intensity White Light
• GE-41415-30 Fuel Tank Cap Adapter
• GE-41415-60 Engine Induction System Leak Test Adapter/Capless Fuel Fill Adapter
• J-41413-300 EVAP Cap and Plug Kit
• J-41413-311 EVAP Plug (Brass Nozzle)
• J-41413-VLV EVAP Service Port Vent Fitting

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools)

Circuit/System Testing

NOTE:

• Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize or produce smoke from a leak.
• Refer to the GE-41413-A detailed instructions in Evaporative Emission System Diagnosis.

1. Disconnect the purge tube at the quick connector on the EVAP canister side of the purge solenoid valve and install the CH-48096.

2. Connect the GE-41413-A to the vehicle EVAP service port adapter.

3. Ignition ON, command the EVAP Purge/Seal function to Not Venting or System Seal with a scan tool to seal the EVAP system.

4. Verify that there is no leak in the EVAP system using the flow meter on the GE-41413-A , calibrated to 0.51 mm (0.020 in).

• If a leak is detected

1. Apply smoke to the EVAP system at the service access port adapter with the GE-41413-A.
2. Locate the leak using the GE-41413-SPT.
   • When the leak is located, repair or replace the affected component as necessary.

• Go to next step: If no leak detected

NOTE: The steps below test for a restriction in the purge path.

5. Connect the GE-41413-A nitrogen/smoke hose to the J-41413-311 or GE-41415-60 for capless vehicles.

6. Disconnect the hose at the fuel cap end of the GE-41415-30 and connect to the J-41413-311.

7. Install the GE-41415-30 or GE-41415-60 , filler neck end only, to the vehicle.

8. Engine idling, command the Purge/Seal function to Not Venting or System Seal with a scan tool to seal the system.

NOTE: The scan tool will abort purge when a predetermined value is reached. This is to prevent damage to the fuel tank.

9. Command the EVAP Purge Solenoid Valve to 10-30% with a scan tool.

10. Verify the vacuum/pressure gauge on the GE-41413-A and the scan tool Fuel Tank Pressure Sensor parameter both show vacuum.

• If the vacuum/pressure gauge shows vacuum but the Fuel Tank Pressure Sensor parameter does not show vacuum

Replace the B150 Fuel Tank Pressure Sensor.

• If both do not show vacuum

Repair the restriction in the purge path.

• Go to next step: If both show vacuum

11. Verify that the Fuel Tank Pressure Sensor parameter increases to greater than 3.2 V, and the pressure values are similar between the scan tool Fuel Tank Pressure Sensor and the vacuum/pressure gauge on the GE-41413-A.

• If not within the specified range

Replace the B150 Fuel Tank Pressure Sensor.

• Go to next step: If within the specified range

12. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Tank Pressure Sensor Replacement (FWD) or Fuel Tank Pressure Sensor Replacement (AWD)
• Control Module References for control module replacement, programming and setup.

DTC P0496

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0496

Evaporative Emission (EVAP) System Flow During Non-Purge

Circuit/System Description

This DTC tests for undesired intake manifold vacuum flow to the evaporative emission (EVAP) system.

The engine control module (ECM) seals the EVAP system by commanding the EVAP purge solenoid valve OFF and the vent solenoid valve ON. The ECM monitors the fuel tank pressure (FTP) sensor to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP purge and vent solenoid valves.

Conditions for Running the DTC

• DTCs P00C8, P00C9, P010C, P010D, P16A0, P16A1, P16A2, P160E, P160D, P16F3, P0068, P0101, P0102, P0103, P0111, P0112, P0113, P0114 P0116, P0117, P0118, P0122, P0123, P0125, P0128, P0191, P0192, P0193, P0222, P0223, P0443, P0449, P0452, P0453, P0454, P0502, P0503, P0601, P0604, P0606, P0722, P0723, P1104, P1682, P2100, P2101, P2102, P2103, P2135, P2176, P2227, P2228, P2229, P2230 are not set.
• The ignition voltage is between 11 - 32 V.
• The engine OFF time is greater than 8 h,
• The barometric pressure (BARO) is greater than 70 kPa.
• The fuel level is between 10 - 90 %.
• The startup engine coolant temperature (ECT) is less than 35ºC (95ºF).
• The startup intake air temperature (IAT) is between 4 - 30ºC (39 - 86ºF).
• DTC P0496 runs once per cold start, for up to 17 min, when the above conditions are met.

Conditions for Setting the DTC

The ECM detects more than 10 in H2O vacuum for 5 s during a non-purge condition.

Action Taken When the DTC Sets

DTC P0496 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P0496 is a Type B DTC.

Diagnostic Aids

An intermittent condition could be caused by an improperly installed or damaged EVAP purge solenoid valve or by a temporary blockage or restriction in the EVAP purge solenoid valve.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Evaporative Emission Control System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

2. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC does not set

3. All OK.

Circuit/System Testing

1. Ignition ON, engine OFF.

2. Seal the EVAP system using the Purge/Seal function with a scan tool.

3. Start the engine.

4. Observe the FTP sensor with a scan tool. The FTP sensor parameter should be less than 1.7 V after 90 s.

• If not within specifications

Replace the Q12 Evaporative Emission Purge Solenoid Valve

• Go to next step: If within Specifications

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Evaporative Emission Canister Purge Solenoid Valve Replacement.

DTC P0506 or P0507

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0506

Idle Speed Low

DTC P0507

Idle Speed High

Circuit/System Description

The throttle actuator control (TAC) motor is a DC motor that is part of the throttle body assembly. The TAC motor drives the throttle valve. The engine control module (ECM) controls the TAC motor based on throttle position sensor input. The idle speed is controlled by the ECM based on various inputs. The ECM commands the TAC motor to open or close the throttle valve in order to maintain the desired idle speed.

Conditions for Running the DTC

• DTCs P0068, P0101, P0102, P0103, P0112, P0113, P0117, P0118, P0121, P0122, P0123, P0171, P0172, P0174, P0175, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268. P0270, P0271, P0273, P0274, P0276, P0277, P0300 - P0306, P0351 - P0356, P0461 - P0464, P0496, P0627, P0628, P0629, P0722, P1516, P2066 - P2068, are not set.
• The barometric pressure (BARO) is greater than 70 kPa.
• The engine coolant temperature (ECT) is greater than 60ºC (140ºF).
• The engine run time is greater than 60 s.
• The ignition voltage is between 11 - 32 V.
• The transmission is not changing gears.
• The torque converter clutch (TCC) is not changing states.
• The intake air temperature (IAT) is warmer than -20ºC (-4ºF).
• The vehicle speed is less than 3 km/h (2 mph).
• The commanded engine speed is steady within 25 RPM.
• The engine is idling for greater than 5 s.
• The DTCs run when the above conditions are met.

Conditions for Setting the DTC

P0506

The actual engine speed is 94 RPM less than the desired idle speed for 10 s.

P0507

The actual engine speed is 188 RPM greater than the desired idle speed for 10 s.

Action Taken When the DTC Sets

DTCs P0506 and P0507 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0506 and P0507 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify there are no other DTCs set.

• If any other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If no other DTCs are set

3. Verify the scan tool Throttle Body Idle Airflow Compensation parameter is less than 90 %.

• If 90 % or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90 %

4. Engine Idling at the normal operating temperature.

5. Verify the actual Engine Speed is not 100 RPM less than the Desired Idle Speed.

• If 100 RPM less than the Desired Idle Speed

Refer to Circuit/System Testing.

• Go to next step: If 100 RPM greater than the Desired Idle Speed

6. Verify the actual Engine Speed is not 200 RPM greater than the Desired Idle Speed.

• If 200 RPM greater than the Desired Idle Speed

Refer to Circuit/System Testing.

• Go to next step: If 200 RPM less than the Desired Idle Speed

7. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

8. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

9. All OK

Circuit/System Testing

P0506

1. Verify the conditions listed below do not exist.
   • Restricted exhaust
   • Mechanical conditions that limits engine speed
   • Parasitic load on the engine - For example, a transmission condition, a belt driven accessory condition.
   • If a condition is found

     Repair as necessary.

   • Go to next step: If a condition is not found

2. All OK.

P0507

1. Verify the conditions listed below do not exist.

• Vacuum leaks
• A throttle valve that does not close correctly
• Verify the correct operation of the crankcase ventilation system. Inspect for the conditions listed below:
  • Improper routing of the positive crankcase ventilation (PCV) system
  • Vacuum leaks in the PCV system - Refer to Crankcase Ventilation System
• Inspection/Diagnosis.
• If a condition is found

Repair as necessary.

• Go to next step: If a condition is not found

2. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Throttle Body Assembly Replacement.

DTC P050D

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P050D

Cold Start Rough Idle

Circuit/System Description

During a cold start, the engine control module (ECM) commands dual-pulse mode during Open Loop operation to improve cold start emissions. In dual-pulse mode, the injectors are energized twice during each injection event. As with misfire diagnosis, in dual-pulse mode the ECM monitors the crankshaft position sensor and the camshaft position sensors to calculate crankshaft rotation speed. In normal operation, optimum fuel delivery during dual-pulse mode produces a steady crankshaft rotation speed. If the variations exceed a calibrated value, the code will be set.

Conditions for Running the DTC

• DTCs P0010, P0011, P0013, P0014, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0101 - P0103, P0106 - P0108, P0112, P0113, P0117 - P0118, P0122, P0123, P0128, P0171, P0172, P0192, P0193, P0201 - P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301 - P0304, P0335, P0336, P0351 - P0354, P0506, P0507, P0628, P0697, P06A3, P0722, P0723, P1248, P1249, P124A, P124B, P182E, P1915, P2122, P2123, P2127, P2128, P2135, P2138, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157 are not set.
• The catalyst temperature is less than 500ºC (932ºF).
• The engine coolant temperature is warmer than -12ºC (10.4ºF).
• The barometric pressure is greater than 75 kPa.
• The engine speed is between 250 - 3000 RPM.
• The accelerator pedal position is less than 1 percent.
• The engine is running for less than 20 s and a cold start has been detected.
• DTC P050D runs once per cold start.

Conditions for Setting the DTC

This DTC will set if the ECM detects variations in crankshaft rotation speed caused by the lack of adequate fuel delivery during dual-pulse mode.

Action Taken When the DTC Sets

• DTC P050D is a Type B DTC.
• The ECM disables dual pulse mode and energizes the fuel injector as it would for a warm engine.

Conditions for Clearing the DTC

DTC P050D is a Type B DTC.

Diagnostic Aids

• This DTC may be set with a misfire DTC, however the existence of this DTC is a higher priority and indicates the condition to diagnose is related to fuel and/or injectors, not the ignition/spark system.
• A restricted fuel injector may cause this DTC to set.
• High resistance in the circuits of the injectors could set this DTC without setting an injector DTC.

  Test the injector circuits of the affected cylinders for a high resistance if you suspect a condition.

• A drop in system voltage during cold start may set this DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: Circuit/System Verification requires cold start. Do not start vehicle prior to connecting scan tool and preparing to evaluate the condition during engine crank.

1. Start the engine and verify that the scan tool Cylinder 1-4 Current Misfire Counters are not incrementing during first 500 engine cycles.

• If Cylinder 1-4 Current Misfire Counters are incrementing

Refer to Circuit/System Testing.

• Go to next step: If Cylinder 1-4 Current Misfire Counters are not incrementing

2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

3. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

4. All OK.

Circuit/System Testing

1. Verify that the fuel pressure is not too low or too high - Refer to Fuel System Diagnosis.

• If a condition is found, repair or replace components as necessary.
• Go to next step: If the fuel pressure is OK

2. Verify that the fuel is not contaminated - Refer to Alcohol/Contaminants-in-Fuel Diagnosis.

• If the fuel is contaminated, clean the fuel system - Refer to Fuel System Cleaning.
• Go to next step: If the fuel is not contaminated

3. Replace fuel injectors as indicated by high misfire counts.

Repair Instructions

Fuel Injector Replacement

Repair Verification

NOTE: Repair Verification requires cold start.

1. Install any components or connectors that have been removed or replaced during diagnosis.

2. Perform any adjustment, programming or setup procedures that are required when a component or module is removed or replaced.

3. Clear the DTCs.

4. Turn OFF the ignition for 60 seconds.

5. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not reset. If the DTC resets or another DTC is present, refer to the Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.

DTC P057B-P057E

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P057B

Brake Pedal Position Sensor Performance

DTC P057C

Brake Pedal Position Sensor Circuit Low Voltage

DTC P057D

Brake Pedal Position Sensor Circuit High Voltage

DTC P057E

Brake Pedal Position Sensor Circuit Erratic

Diagnostic Fault Information

Typical Scan Tool Data

Brake Pedal Position Sensor

Circuit/System Description

The brake pedal position (BPP) sensor is part of the engine brake pedal override feature. The engine control module (ECM) continuously monitors the vehicle speed and the position of the brake pedal.

These two main inputs, along with other ECM inputs are used to determine if the vehicle is decelerating at the proper speed and rate with the brake pedal applied. When the engine brake pedal override system is active, the ECM reduces engine torque to assist in reducing vehicle speed.

The BPP sensor is a six wire sensor, and is part of a dual brake position sensor. One BPP Sensor is used for the stop lamps and the other BPP Sensor is used for the engine brake pedal override feature. The BPP Sensor for engine brake pedal override communicates with the ECM. The ECM supplies a 5 V reference circuit, low reference circuit, and signal circuit to the BPP sensor. The BPP sensor sends a voltage signal to the ECM on the signal circuit. The voltage on the signal circuit will vary from a voltage greater than 0.25 V when the brake pedal is released to a voltage less than 4.75 V when the brake pedal is fully applied.

For information on the Stop Lamps side of the BPP Sensor, refer to Exterior Lighting Systems Description and Operation.

Conditions for Running the DTC

P057B

• DTCs P057C, or P057D are not set.
• Ignition voltage is greater than 10 V.
• Shift lever has been in Park at least once during key ON.
• Shift lever is not in Park.
• Vehicle speed is greater than 8 Km/h (5 mph).
• Accelerator Pedal Position is less than 5 %.
• DTC runs once per key cycle when above conditions are met.

P057C, P057D, or P057E

• Ignition voltage is greater than 10 V.
• DTC runs continuously when above condition is met.

Conditions for Setting the DTC

P057B

ECM detects the BPP sensor signal is stuck in a range for greater than 1 s.

P057C

ECM detects the BPP sensor voltage is less than 0.25 V greater than 1 s.

P057D

ECM detects the BPP sensor voltage is greater than 4.75 V greater than 1 s.

P057E

ECM detects the BPP sensor value varies greater than a calibrated value.

Action Taken When the DTC Sets

• P057B, P057C, P057D, and P057E are Type A DTCs.
• Brake Pedal Position Sensor parameter defaults to 0 %.

Conditions for Clearing the DTC

P057B, P057C, P057D, and P057E are Type A DTCs

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LTG)
• Exterior Lights Wiring Schematics

Connector End View Reference

• Component Connector End View Index
• Inline Harness Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: The Brake Pedal Position sensor scan tool data is located in the ECM automatic transmission data list.

1. Ignition ON.

2. Verify DTC P0641, P0651, P0697, or P06A3 is not set.

• If any of the DTCs are set

Refer to DTC P0641, P0651, P0697, P06A3, or P06D2.

• Go to next step: If none of the DTCs are set

3. Transmission in Park, and service brake pedal released.

4. Verify the scan tool Brake Pedal Position Sensor parameter in the ECM displays greater than 0.25 V.

• If 0.25 V or less

Refer to Circuit/System Testing.

• Go to next step: If greater than 0.25 V

5. Verify the scan tool Brake Pedal Position Sensor parameter voltage changes as the brake pedal is applied and displays less than 4.75 V when the brake pedal is fully applied.

• If the voltage does not change, or is greater than 4.74 V

Refer to Circuit/System Testing.

• Go to next step: If the voltage changes and less than 4.75 V

6. Verify the scan tool Brake Pedal Position Sensor Learned Release Position parameter is within 0.1 V of the Brake Pedal Position Sensor parameter when the brake pedal is fully released.

• If difference is greater than 0.1 V

Perform the Brake Pedal Position Sensor Calibration.

• Go to next step: If difference is 0.1 V or less

7. Verify the Brake Pedal Position Sensor parameter transitions smoothly without any spikes or dropouts when slowly applying and releasing the brake pedal.

• If parameter does not transition smoothly or has spikes or dropouts

Refer to Circuit/System Testing.

• Go to next step: If parameter transitions smoothly and there are no spikes or dropouts

8. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

9. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

10. All OK.

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification first.

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B22 Brake Pedal Position Sensor. It may take up to 2 minutes for all vehicle systems to power down.

NOTE: All terminal references are for the vehicle harness brake pedal position sensor connector.

2. Test for less than 10 Ω between the low reference circuit terminal 5 and ground.

• If 10 Ω or greater

1. Disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 10 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 6 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance.
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool Brake Pedal Position Sensor parameter is less than 0.25 V.

• If 0.25 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 0.25 V between the signal circuit terminal 4 and ground.
   • If 0.25 V or greater, repair the short to voltage on the circuit.
   • If less than 0.25 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.25 V

6. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the 5 V reference circuit terminal 6.

7. Verify the scan tool Brake Pedal Position Sensor parameter is greater than 4.8 V.

• If 4.8 V or less

1. Ignition OFF, remove the jumper wire, and disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 4 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance.
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.
   • Go to next step: If greater than 4.8 V

8. Replace the B22 Brake Pedal Position Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Brake Pedal Position Sensor Replacement
• Perform the Brake Pedal Position Sensor Calibration following the replacement of the ECM or BPP sensor, or any repair that effects the BPP sensor alignment.
• Control Module References for Engine Control Module replacement, programming and setup.

DTC P05CC or P05CE

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P05CC

Cold Start Intake Camshaft Position System Performance

DTC P05CE

Cold Start Exhaust Camshaft Position System Performance

Circuit/System Description

The camshaft position actuator system enables the engine control module (ECM) to change the timing of the camshafts while the engine is operating. The camshaft position actuator solenoid valves are each supplied a dedicated pulse width modulated (PWM) control circuit and low reference circuit from the ECM. The ECM operates each camshaft position actuator solenoid valve by controlling the amount of solenoid valve signal duty cycle to control the oil flow that applies the pressure to advance or retard the camshafts.

Conditions for Running the DTC

• DTC P0010, P0016, P0017, P0018, P0019, P0335, P0336, P0340, P0341, P0345, P0346, P0365, P0366, P0390 or P0391, is not set.
• Ignition voltage is greater than 11 V.
• Engine is running.
• Desired camshaft position is greater than 0 degrees.
• Desired camshaft position is not changing greater than 4.5º for at least 1 s.
• Both of the desired and actual camshaft position actuator values cannot be greater than 20 degrees or less than 5 degrees.

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects the difference between the desired and actual camshaft position angle is greater than 4.5 degrees for greater 1 s.

Action Taken When the DTC Sets

DTCs P05CC and P05CE are type B DTCs.

Conditions for Clearing the DTC

DTCs P05CC and P05CE are type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Description and Operation

Camshaft Actuator System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 35616-200 Test Lamp Kit

Diagnostic Aids

• A low oil level or condition may set this DTC.
• Inspect the engine for any recent engine mechanical repairs. An incorrectly installed camshaft, camshaft actuator, or timing chain can cause this DTC to set.

Circuit/System Verification

NOTE:

• The engine oil level and the oil pressure are critical to the correct operation of the camshaft position actuator system. Verify that the engine has the correct oil level and the correct oil pressure before continuing with this diagnostic.
• The engine oil condition has a major impact on the camshaft actuator system. Debris in the oil can interfere with the camshaft position actuator solenoid and the mechanical camshaft actuator operation. Inspect for dirty or degraded crankcase oil. The engine may require an oil change. Inquire with the customer when the last oil change was performed. You may also monitor the scan tool Engine Oil Life Remaining parameter. Advise the customer an oil change may be required.

1. Verify the engine has the proper oil condition, level, and pressure. Refer to Oil Pressure Diagnosis and Testing.

• If the oil condition, level, and oil pressure are not correct

Repair as necessary

• Go to next step: If the oil condition, level, and oil pressure are correct

NOTE: If a crankshaft or camshaft position sensor DTC is set, the scan tool Camshaft Position Actuator output control will not function.

2. Verify DTC P0010, P0016, P0017, P0018, P0019, P0335, P0336, P0340, P0341, P0345, P0346, P0365, P0366, P0390 or P0391, is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Engine Running at normal operating temperature.

4. Verify the scan tool parameters below are less than 2º in each of the commanded states when commanding the Camshaft Position Actuator from 0 - 20º and back to 0º.

• Intake Camshaft Position Variance
• Exhaust Camshaft Position Variance
• If 2º or greater

Refer to Circuit/System Testing.

• Go to next step: If less than 2º

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

6. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTCs does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF and all vehicle systems Off, disconnect the appropriate harness connector at the Q6 Camshaft Position Actuator Solenoid Valve. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 2 or B and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

NOTE: A test lamp must be used for this test. The control circuit is pulledup to a low current voltage, 1.5 - 4.5 V on the control circuit is normal.

4. Verify that a test lamp does not illuminate between the control circuit terminal 1 or A and ground.

• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

5. Remove the test lamp.

6. Ignition ON.

7. Verify the scan tool Camshaft Position Actuator Solenoid Valve Control Circuit Low Voltage Test Status changes between OK and Not Run when commanding the Camshaft Position Actuator Solenoid Valve On and Off.

• If the parameter does not change

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance or short to ground in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If the parameter changes

NOTE: If debris is found on Q6 Camshaft Position Actuator Solenoid Valve screens, clean the screens and reinspect for damage. If the screens are not damaged, reinstall in the engine.

8. Ignition OFF, remove the Q6 Camshaft Position Actuator Solenoid Valve.

9. Verify the following conditions do not exist:

• Damaged, restricted, or missing screens on the Q6 Camshaft Position Actuator Solenoid Valve.
• Surface damage or an engine oil leak between the oil sealing lands of the Q6 Camshaft Position Actuator Solenoid Valve.
• Oil seepage at the Q6 Camshaft Position Actuator Solenoid Valve connector.
• If a condition is found.

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If a condition is not found

NOTE: After exchanging the solenoids, install jumper wires to the appropriate terminals of the harness connectors and the solenoids.

10. Ignition OFF, exchange the suspect Q6 Camshaft Position Actuator Solenoid Valve with the Q6 Camshaft Position Actuator Solenoid Valve that is operating correctly.

11. Engine Running.

12. Verify the scan tool Camshaft Position Variance parameter is less than 2º in each of the commanded states when commanding the Camshaft Position Actuator from 0 - 20º and back to 0º.

• If 2º or greater

Replace the mechanical camshaft position actuator.

• Go to next step: If less than 2º

13. Test or replace the Q6 Camshaft Position Actuator Solenoid Valve.

Component Testing

1. Ignition OFF, disconnect the harness connector at the appropriate Q6 Camshaft Position Actuator Solenoid Valve.

2. Test for 7-12 Ω between the control terminal 1 or A and the low reference circuit terminal 2 or B.

• If not between 7-12 Ω

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If between 7-12 Ω

3. Test for infinite resistance between each terminal and the Q6 Camshaft Position Actuator Solenoid Valve housing.

• If not infinite resistance

Replace the Q6 Camshaft Position Actuator Solenoid Valve.

• Go to next step: If infinite resistance

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Camshaft Position Actuator and Camshaft Replacement - Intake
• Camshaft Position Actuator and Camshaft Replacement - Exhaust
• Camshaft Position Actuator Exhaust Solenoid Valve Replacement
• Camshaft Position Actuator Intake Solenoid Valve Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P0601-P0604, P0606, P062B, P062F, P0630, P064D, P16F3, or P262B

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each of the diagnostic category.

DTC Descriptors

DTC P0601

Control Module Read Only Memory Performance

DTC P0602

Control Module Not Programmed

DTC P0603

Control Module Long Term Memory Reset

DTC P0604

Control Module Random Access Memory Performance

DTC P0606

Control Module Processor Performance

DTC P062B

Control Module Fuel Injector Control Performance

DTC P062F

Control Module Long Term Memory Performance

DTC P0630

VIN Not Programmed or Mismatched - Engine Control Module (ECM)

DTC P064D

Control Module H02S System Circuitry Performance

DTC P16F3

Control Module Redundant Memory Performance

DTC P262B

Control Module Power Off Timer Performance

Circuit/System Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses if the ECM is not programmed.

Conditions for Running the DTCs

P0601, P0602, P0630

These DTCs run continuously when the ignition is in ON.

P0603, P062F

These DTCs run once per ignition cycle.

P0604, P064D

DTC P0604 runs continuously when the ignition is ON for greater than 30 s.

P0606, P062B

These DTCs run continuously when Ignition 1 Signal voltage is greater than 11 V.

P16F3

• The engine speed is greater than 680 RPM.
• DTCs P0101, P0102, P0103, P0106, P0107, P0108, P2227, P2228, P2229, or P2230 are not set.
• DTC P16F3 runs continuously when the above conditions are met.

P262B

DTC P262B runs during ECM power down.

Conditions for Setting the DTCs

The ECM detects an internal failure or incomplete programming for more than 10 s.

Actions Taken When the DTC Sets

• DTCs P0601, P0602, P0603, P0604, P0606, P062B, P0630, and P16F3 are Type A DTCs.
• DTC P062F is a Type C DTC.
• DTCs P064D and P262B are Type B DTCs.

Conditions for Clearing the MIL/DTC

• DTCs P0601, P0602, P0603, P0604, P0606, P062B, P0630, and P16F3 are Type A DTCs.
• DTC P062F is a Type C DTC.
• DTCs P064D and P262B are Type B DTCs.

Diagnostic Aids

Low voltage or a momentary loss of power or ground to the ECM may cause a DTC to set. Verify the following:

• The battery cables are clean and tight, and the battery is fully charged. Refer to Battery Inspection/Test.
• The ECM ground circuits do not have an open or high resistance.
• The ECM power circuits do not have an open, short to ground, or high resistance.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, clear the DTC information with a scan tool.

2. Verify no other DTCs are set.

• If any other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If no other DTCs are set

3. Verify DTC P0602 or P0630 is not set.

• If any of the DTCs are set

1. Program the K20 Engine Control Module. Refer to Control Module References.
2. Verify DTC P0602 or P0630 is not set.
   • If any of the DTCs are set, replace the K20 Engine Control Module.
   • Go to next step: If none of the DTCs are set
3. All OK.

• Go to next step: If none of the DTCs are set

4. Verify DTC P0601, P0603, P0604, P0606, P062B, P062F, P064D, P16F3, or P262B is not set.

• If any of the DTCs are set

Replace the K20 Engine Control Module.

• Go to next step: If none of the DTCs are set

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for engine control module replacement, programming, and setup.

DTC P0627-P0629

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0627

Fuel Pump Enable Circuit

DTC P0628

Fuel Pump Enable Circuit Low Voltage

DTC P0629

Fuel Pump Enable Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) provides ignition voltage to the fuel pump driver control module whenever the engine is cranking or running. The ECM enables the fuel pump driver control module as long as the engine is cranking or running, and ignition system reference pulses are received. While this enable voltage is being received, the fuel pump driver control module supplies a varying voltage to the in-tank fuel pump module in order to maintain the desired fuel line pressure.

Conditions for Running the DTC

• The engine speed is greater than 0 RPM.
• The ignition voltage is greater than or equal to 11 V.
• The fuel pump enable circuit is commanded ON.
• The DTCs run continuously when the conditions above are met.

Conditions for Setting the DTC

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for 2.5 s.

Action Taken When the DTC Sets

DTCs P0627, P0628, and P0629 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0627, P0628, and P0629 are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P0627, P0628, or P0629 is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If a DTC is not set

3. Verify the parameters listed below do not display Malfunction when commanding the Fuel Pump Enable On and Off with a scan tool.

• Fuel Pump Enable Circuit Low Voltage Test Status
• Fuel Pump Enable Circuit Open Test Status
• Fuel Pump Enable Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the K111 Fuel Pump Driver Control Module harness connector.

2. Ignition ON for 10 s.

3. Verify that a test lamp does not illuminate between the control circuit terminal 2 and ground.

• If the test lamp illuminates

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool Fuel Pump Enable Circuit Low Voltage Test Status parameter is OK when commanding the Fuel Pump Enable On with a scan tool.

• If OK is not displayed

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal 2 and ground.

7. Verify the scan tool Fuel Pump Enable Circuit Low Voltage Test Status parameter is Malfunction when commanding the Fuel Pump Enable On with a scan tool.

• If Malfunction is not displayed

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If Malfunction is displayed

8. Test or replace the K111 Fuel Pump Driver Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD)
• Control Module References for control module replacement, programming and setup.

DTC P0641, P0651, P0697, P06A3, or P06D2

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0641

5V Reference 1 Circuit

DTC P0651

5V Reference 2 Circuit

DTC P0697

5V Reference 3 Circuit

DTC P06A3

5V Reference 4 Circuit

DTC P06D2

5V Reference 5 Circuit

Circuit/System Description

The engine control module (ECM) has 5 internal 5V reference circuits. Each internal reference circuit provides external 5V reference circuits for one or more sensors. A short to ground or short to voltage on one external 5V reference circuit can affect all the components connected to the same internal 5V reference circuit.

Conditions for Running the DTC

These DTCs run continuously when the ignition voltage is greater than 6.4 V.

Conditions for Setting the DTC

The ECM detects a short to ground or voltage on any of the 5V reference circuits for greater than 0.5 s.

Action Taken When the DTC Sets

DTCs P0641, P0651, P0697, P06A3, and P06D2 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P0641, P0651, P0697, P06A3, and P06D2 are Type A DTCs.

Diagnostic Aids

The 5V reference 1 circuit provides 5 V to the components listed below:

• Air conditioning (A/C) refrigerant pressure sensor
• Center console multifunction switch
• Exhaust and intake camshaft position sensors
• Fuel pressure sensor
• Manifold absolute pressure sensor

The 5V reference 2 circuit provides 5 V to the sensors listed below:

• Brake booster vacuum sensor
• Brake pedal position sensor
• Crankshaft position sensor
• Engine oil pressure sensor
• Turbocharger boost/intake air temperature sensor

The 5V reference 3 circuit provides 5 V to the accelerator pedal position sensor 2.

The 5V reference 4 circuit provides 5 V to the sensors listed below:

• Accelerator pedal position sensor 1
• Throttle position sensor

The 5V reference 5 circuit provides 5 V to the sensors listed below:

• Fuel rail pressure sensor
• Multifunction intake air sensor

Disconnecting one component at a time from the affected 5V reference circuit while observing the scan tool 5V Reference Circuit Status parameter may help locate the fault. The scan tool parameter will change from Malfunction to OK when the source of the fault is disconnected. If all 5V reference components have been disconnected and a fault is still indicated, the fault may exist in the wiring harness.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify scan tool 5V Reference 1-5 Circuit Status parameters do not display Malfunction.

• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

5. All OK.

Circuit/System Testing

NOTE: Additional DTCs will set when disconnecting the components.

1. Ignition OFF, disconnect the harness connector at all appropriate sensors for the applicable DTC.

Refer to Diagnostic Aids.

2. Ignition ON.

3. Test for 4.8 - 5.2 V between one of the 5V reference circuits and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module.
2. Test for infinite resistance between the 5V reference circuit for each applicable component and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connectors at the K20 Engine Control Module.
2. Test for less than 1 V between the 5V reference circuit for each applicable component and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

NOTE: A short to voltage or ground on the signal circuit of certain components may cause this DTC to set.

4. Verify the appropriate scan tool 5V Reference 1, 2, 3, 4, or 5 Circuit Status parameter displays OK while connecting each component associated with the 5V reference circuit one at a time.

• If OK is not displayed when a component is connected

Test the signal circuit of the component for a short to ground or voltage. If the circuit tests normal, replace the component.

• Go to next step: If OK is displayed after all components have been connected

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Accelerator Pedal with Position Sensor Assembly Replacement
• Air Conditioning (A/C) Refrigerant Pressure Sensor Replacement
• Brake Pedal Position Sensor Replacement
• Camshaft Position Sensor Replacement - Exhaust
• Camshaft Position Sensor Replacement - Intake
• Crankshaft Position Sensor Replacement
• Engine Oil Pressure Sensor Replacement
• Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement
• Fuel Pressure Sensor Replacement - Fuel Feed Pipe (AWD) or Fuel Pressure Sensor Replacement - Fuel Feed Pipe (FWD)
• Intake Air Pressure and Temperature Sensor Replacement for turbocharger boost/intake air temperature sensor replacement.
• Manifold Absolute Pressure Sensor Replacement
• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement.
• Throttle Body Assembly Replacement
• Control Module References for engine control module replacement, programming, and setup.

DTC P0650, P263A, or P263B

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P0650

Malfunction Indicator Lamp (MIL) Control Circuit Open

DTC P263A

Malfunction Indicator Lamp (MIL) Control Circuit Low Voltage

DTC P263B

Malfunction Indicator Lamp (MIL) Control Circuit High Voltage

Diagnostic Fault Information

Circuit/System Description

The malfunction indicator lamp (MIL) illuminates to inform the driver that an emission system fault has occurred and the powertrain control system requires service. Ignition voltage is supplied directly to the MIL. The engine control module (ECM) turns the MIL ON by grounding the MIL control circuit when the emission system fault occurs. Under normal operating conditions, the MIL should be ON only when the ignition is ON and the engine is OFF.

Conditions for Running the DTC

• The engine speed is greater than 80 RPM.
• The ignition voltage is between 11 - 32 V.
• The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

DTC P0650 or DTC P263A

The ECM detects low voltage during the MIL control circuit driver OFF state. This indicates either a shorted to ground or an open MIL control circuit.

DTC P263B

The ECM detects high voltage on the MIL control circuit during the driver ON state. This indicates a shorted to voltage MIL control circuit.

Action Taken When the DTC Sets

DTC P0650, P263A, and P263B are Type B DTCs

Conditions for Clearing the DTC

DTC P0650, P263A, and P263B are Type B DTCs

Diagnostic Aids

• If the condition is intermittent, move the related harnesses and connectors while monitoring the scan tool MIL control circuit status parameters. Perform this test with the ignition ON and the engine OFF, and with the engine running. The MIL control circuit status parameters change from OK or Not Run to Malfunction if there is a condition with a circuit or a connection.
• If the ECM detects low voltage on the MIL control circuit during the control circuit driver OFF state, DTCs P0650 and DTC P263A may set simultaneously.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LTG)
• Instrument Cluster Wiring Schematics

Connector End View Reference

• Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify the parameters listed below do not display Malfunction when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• The MIL Control Circuit Low Voltage Test Status
• The MIL Control Circuit Open Test Status
• The MIL Control Circuit High Voltage Test Status

If Malfunction is displayed

• Refer to Circuit/System Testing.

3. Engine running.

4. Verify the parameters listed below do not display Malfunction when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• The MIL Control Circuit Low Voltage Test Status
• The MIL Control Circuit Open Test Status
• The MIL Control Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

5. Verify the malfunction indicator lamp turns ON and OFF when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• If the malfunction indicator lamp does not turn ON and OFF

Refer to Circuit/System Testing.

• Go to next step: If the malfunction indicator lamp turns ON and OFF

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If the DTC does not set

7. All OK.

Circuit/System Testing

1. Ignition OFF.

2. Disconnect the X1 harness connector at the K20 Engine Control Module.

3. Ignition ON, verify the malfunction indicator lamp does not illuminate.

• If the malfunction indicator lamp illuminates

1. Test for infinite resistance between the control circuit terminal X1 71 and ground.
   • If less than infinite resistance, repair the short to ground in the circuit.
   • If infinite resistance, replace the P16 Instrument Cluster.

• Go to next step: If the malfunction indicator lamp does not illuminate

4. Connect a 3 A fused jumper wire between the control circuit terminal X1 71 and ground.

5. Verify the malfunction indicator lamp illuminates.

• If the malfunction indicator lamp illuminates

Replace the K20 Engine Control Module.

• If the malfunction indicator lamp does not illuminate

1. Test for less than 1 V between the control circuit terminal X1 71 and ground.
   • If 1 V or greater, repair the short to voltage in the circuit.
   • Go to next step: If less than 1 V
2. Ignition OFF.
3. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω.

6. Ignition OFF, disconnect the harness connector at the instrument cluster.

7. Ignition ON, verify a test lamp illuminates between the between the ignition voltage circuit terminal X1 8 and ground.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground in the circuit.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.

• Go to next step: If the test lamp illuminates

8. Replace the P16 Instrument Cluster.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Instrument Cluster Replacement
• Control Module References for control module replacement, programming, and setup

DTC P0685-P0687, P0689, P0690, or P1682

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0685

Engine Controls Ignition Relay Control Circuit

DTC P0686

Engine Controls Ignition Relay Control Circuit Low Voltage

DTC P0687

Engine Controls Ignition Relay Control Circuit High Voltage

DTC P0689

Engine Controls Ignition Relay Feedback Circuit Low Voltage

DTC P0690

Engine Controls Ignition Relay Feedback Circuit High Voltage

DTC P1682

Ignition 1 Switch Circuit 2

Diagnostic Fault Information

Engine Controls Ignition Relay

Typical Scan Tool Data

Engine Controls Ignition Relay Control Circuit Low Voltage, Open, and High Voltage Test Status - Component Commanded OFF

Engine Controls Ignition Relay Control Circuit Low Voltage, Open, and High Voltage Test Status - Component Commanded ON

Circuit/System Description

There are 2 ignition voltage circuits supplied to the engine control module (ECM). One is supplied by the engine controls ignition relay, and the other is supplied by the ignition main relay. The ECM monitors and compares the ignition voltage supplied by the 2 relays.

Conditions for Running the DTC

P0685, P0686, P0687

The DTC runs when Ignition 1 signal voltage is greater than 11 V.

P0689

• DTC P0685 is not set.
• The engine controls ignition relay is commanded ON.
• Ignition 1 signal voltage is greater than 11 V.
• The DTC runs continuously when the above conditions are met.

P0690

• DTC P0685 is not set.
• The engine controls ignition relay is commanded OFF.
• The DTC runs continuously when the above conditions are met.

P1682

• The engine controls ignition relay is commanded ON.
• Ignition voltage is greater than 5.5 V.
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

P0685

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 2 s.

P0686

The ECM detects a short to ground on the control circuit for greater than 2 s.

P0687

The ECM detects a short to voltage on the control circuit for greater than 2 s.

P0689

The ECM detects the engine controls ignition relay feedback circuit is less than 5 V.

P0690

The ECM detects the engine controls ignition relay feedback circuit is greater than 4 V for greater than 5 s.

P1682

The ECM detects that the voltage level difference is greater than 3 V between the 2 ignition voltage circuits for greater than 1 s.

Action Taken When the DTC Sets

North America

• DTCs P0685, P0686, P0687, and P0690 are Type B DTCs.
• DTC P0689 is a Type C DTC.
• DTC P1682 is a Type A DTC.

Europe

• DTCs P0685, P0686, P0687, P0689, and P0690 are Type C DTCs.
• DTC P1682 is a Type A DTC.

Conditions for Clearing the DTC

North America

• DTCs P0685, P0686, P0687, and P0690 are Type B DTCs.
• DTC P0689 is a Type C DTC.
• DTC P1682 is a Type A DTC.

Europe

• DTCs P0685, P0686, P0687, P0689, and P0690 are Type C DTCs.
• DTC P1682 is a Type A DTC.

Diagnostic Aids

The engine controls ignition relay may also be labeled the powertrain relay, the engine control module relay, or the main relay. The ignition main relay may also be labeled the run/crank relay, the ignition run relay, the ignition 1 relay, or the ignition relay.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LTG)
• Power Distribution Wiring Schematics

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Electrical Center Identification Views
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: A short to voltage on other components may cause DTC P0690 to set. If any other DTC is set, diagnose that DTC first.

If you were sent here from Engine Cranks But Does Not Run, proceed to Circuit/System Testing.

1. Ignition ON, observe the scan tool DTC information. Verify DTC P0685, P0686, P0687, P0689, P0690, or P1682 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

3. All OK.

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing unless sent here from Engine Cranks But Does Not Run.

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.

2. Verify a test lamp illuminates between ground and the relay circuit terminals listed below:

• Terminal 85
• Terminal 30
• If the test lamp does not illuminate

Replace the front compartment fuse block.

• Go to next step: If the test lamp illuminates

NOTE:

• Go to next step: High resistance in the circuit/underhood fuse block for either the KR75 Engine Controls Ignition Relay or the KR73 Ignition Main Relay can cause DTC P1682 to set.
• Go to next step: A short to voltage on any of the circuits supplied by the engine controls ignition relay can cause DTC P0690 to set.

3. Ignition ON.

4. Verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground.

• If the test lamp illuminates

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module.
2. Ignition ON.
3. Test for less than 1 V between ground and connector terminals 73.
   • If 1 V or greater, repair the short to voltage in the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

5. Ignition OFF, connect a 20 A fused jumper wire between the relay switch B+ circuit terminal 30 and the relay switch ignition voltage circuit terminal 87.

6. Ignition ON.

7. Verify the scan tool Engine Controls Ignition Relay Feedback Signal parameter displays B+.

• If B+ is not displayed

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module
2. Test for less than 2 Ω in the relay switch ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω
3. Test for infinite resistance between the relay switch ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If B+ is displayed

8. Ignition OFF, connect a DMM, set to the diode setting, between control circuit terminal 86 and ground.

9. Verify the DMM displays OL.

• If OL is not displayed

1. Disconnect the X1 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between ground and the relay control circuit.
   • If less than infinite resistance, repair the short to ground in the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If OL is displayed

10. Ignition ON.

11. Verify the DMM displays less than 1 V.

• If 1 V or greater

1. Ignition OFF, disconnect the X1 connector at the K20 Engine Control Module.
2. Ignition ON.
3. Test for less than 1 V on the relay control circuit.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
4. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • if less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 1 V

12. Test or replace the KR75 Engine Controls Ignition Relay.

Component Testing

Relay Test

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.

2. Test for 70 - 110 Ω between terminals 85 and 86:

• If less than 70 Ω or greater than 110 Ω

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If between 70 - 110 Ω

3. Test for infinite resistance between the terminals listed below:

• 30 and 86
• 30 and 87
• 30 and 85
• 85 and 87
• If less than infinite resistance

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If infinite resistance

4. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.

5. Test for less than 2 Ω between terminals 30 and 87.

• If 2 Ω or greater

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If less than 2 Ω

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Engine Wiring Harness Junction Block Replacement (LTG) or Engine Wiring Harness Junction Block Replacement (LGX) for front compartment fuse block replacement.
• Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center)
• Control Module References for engine control module replacement, programming, and setup.

DTC P0700

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each of the diagnostic category.

DTC Descriptor

DTC P0700

Transmission Control Module Requested MIL Illumination

Circuit/System Description

The Transmission Control Module (TCM) constantly monitors the transmission system for any condition which may adversely affect vehicle emissions. If a condition is detected, the TCM sets a DTC and sends a serial data message to the ECM. The ECM sets DTC P0700 to inform the technician that the TCM has set the emission related DTC. The serial data message sent by the TCM also contains a request for the ECM to illuminate the Malfunction Indicator Lamp (MIL) The technician can observe the DTC that was set by the TCM by reviewing the ECM Freeze Frame records on the scan tool. The ECM Freeze Frame records also contain the engine operating conditions present when the transmission DTC set.

Conditions for Running the DTC

• The ignition is ON or the engine is running.
• DTC P0700 runs continuously.

Conditions for Setting the DTC

The ECM receives a serial data message from the TCM indicating that an emission related DTC has set in the TCM.

Action Taken When the DTC Sets

DTC P0700 is a Type A DTC.

Conditions for Clearing the MIL/DTC

DTC P0700 is a Type A DTC.

Diagnostic Aids

Communication codes, U-codes, as well as powertrain codes, P-codes, set in the TCM can cause the TCM to request DTC P0700 to be set in the ECM.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE:

• Do not replace the engine control module for this DTC. DTC P0700 is an informational DTC.
• Correct any engine control and communication DTCs before diagnosing transmission control module DTCs.

1. Verify there are no engine control or communication DTCs set.

• If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If a DTC is not set

2. Verify there are no transmission control module DTCs set.

• If a DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If a DTC is not set

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If the DTC does not set

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

DTC C1201, P1000, P1001, P1003, P1008, P1009, P100A, P100E, P103D, P103E, P10B6-P10B9, P10BF, P10C6-P10C8, P10F5, P1100, P1103, P117A, P11FF, P1200, P128C-P128F, P129E, P12A8, P130F, P135C-P135F, P1436, P143A, P143B, P1472, P14A0, P14B6, P14BD, P14CD, P14CE, P14D4-P14D6, P150C, P151A, P151D, P153C, P153D, P155D, P1591, P15E2, P15F2, P15F9, P15FA, P15FB, P165C, P167F, P16E8, P16FF, P175F, P1761, P1762, P1775, P179B, P189C, P2544, P308D, P30B4, P30B5, P30BC, P30BD, P30D5, P30DE, P3168, P3169, or P316B

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis:Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC C1201

Transmission Range Redundant Command Message Counter Incorrect

DTC P1000

Fuel Pump Driver Control Module Reset Count Message Counter Incorrect

DTC P1001

Evaporative Emission (EVAP) System Signals Message Counter Incorrect

DTC P1003

Fuel Composition Signals Message Counter Incorrect

DTC P1008

Engine Coolant Bypass Valve Command Signal Message Counter Incorrect

DTC P1009

Fuel Pump Driver Control Module Temperature High Signal Message Counter Incorrect

DTC P100A

Turbocharger Boost Control Signal Message Counter Incorrect

DTC P100E

Accelerator Pedal Position Signal Message Counter Incorrect

DTC P103D

Engine Coolant Pump Control Signal Message Counter Incorrect

DTC P103E

Auxiliary Coolant Pump Control Signal Message Counter Incorrect

DTC P10B6

Mass Air Flow Sensor Intake Air Signals Message Counter Incorrect Bank 1

DTC P10B7

Mass Air Flow Sensor Intake Air Signals Message Counter Incorrect Bank 2

DTC P10B8

Mass Air Flow Sensor Barometric Pressure Sensor Signal Message Counter Incorrect Bank 2

DTC P10B9

Mass Air Flow Sensor Barometric Pressure Sensor Signal Message Counter Incorrect Bank 1

DTC P10BF

Engine Coolant Bypass Valve Secondary Command Signal Message Counter Incorrect

DTC P10C6

Engine Diagnostic Status Signal Message Counter Incorrect

DTC P10C7

Reductant Control System Signal Message Counter Incorrect

DTC P10C8

Reductant Temperature Signal Message Counter Incorrect

DTC P10F5

EVAP Purge Pump Status Message Counter Incorrect

DTC P1100

Fuel Level Sensor 2 Signal Message Counter Incorrect

DTC P1103

Water in Fuel Signal Message Counter Incorrect

DTC P117A

Engine Block Coolant Valve Signal Message Counter Incorrect

DTC P11FF

Fuel Pump Command Signal Message Counter Incorrect

DTC P1200

Fuel Level Sensor 1 Signal Message Counter Incorrect

DTC P128C

Fuel Rail Temperature Sensor 1 Signal Message Counter Incorrect

DTC P128D

Fuel Rail Temperature Sensor 2 Signal Message Counter Incorrect

DTC P128F

Fuel Rail Pressure Sensors 1 and 2 Signals Message Counter Incorrect

DTC P129E

Fuel Pump Driver Control Module Signal Message Counter Incorrect

DTC P12A8

Fuel Pump Control Status Signal Message Counter Incorrect

DTC P130F

Ignition On/Start Voltage Signal Message Counter Incorrect

DTC P135C

Cooling Fan 1 Status Signals Message Counter Incorrect

DTC P135D

Cooling Fan 2 Status Signals Message Counter Incorrect

DTC P135E

Cooling Fan 3 Status Signals Message Counter Incorrect

DTC P135F

Cooling Fan 4 Status Signals Message Counter Incorrect

DTC P1436

Particulate Matter Sensor Control Module Temperature Signal Message Counter Incorrect

DTC P143A

Reductant Control System Diagnostic Signal Message Counter Incorrect

DTC P143B

Reductant Control System Information Signal Message Counter Incorrect

DTC P1472

Particulate Matter Sensor Signal Message Counter Incorrect

DTC P14A0

Charge Air Cooler Coolant Pump Status Signal Message Counter Incorrect

DTC P14B6

Mass Air Flow Sensor Signal Message Counter Incorrect

DTC P14BD

Mass Air Flow Sensor Signal Message Counter Incorrect Bank 2

DTC P14CD

Fuel Pump Driver Control Module Configuration Command Signal 1 Message Counter Incorrect

DTC P14CE

Fuel Pump Driver Control Module Configuration Status Signal Message Counter Incorrect

DTC P14D4

Fuel Pump Driver Control Module Configuration Command Signal 2 Message Counter Incorrect

DTC P14D5

Fuel Pump Driver Control Module Configuration Command Signal 3 Message Counter Incorrect

DTC P14D6

Fuel Pump Driver Control Module Configuration Command Signal 5 Message Counter Incorrect

DTC P150C

Transmission Control Module Engine Speed Request Signal Message Counter Incorrect

DTC P151A

Throttle Actuator Control (TAC) Signal Message Counter Incorrect

DTC P151D

Transmission Control Module Engine Shutdown Request Signal Message Counter Incorrect

DTC P153C

Engine Speed Signal Message Counter Incorrect

DTC P153D

Driver Torque Request Signal Message Counter Incorrect

DTC P155D

Hill Descent Control Message Counter Incorrect

DTC P1591

Body Control Module Engine Speed Request Signal Message Counter Incorrect

DTC P15E2

Alternative Fuel System Request Signal Message Counter Incorrect

DTC P15F2

Engine Torque Command Signal Message Counter Incorrect

DTC P15F9

Hybrid/EV System Engine Speed Control Intervention Request Type Signal Message Counter Incorrect

DTC P15FA

Wheel Slip Status Signal Message Counter Incorrect

DTC P15FB

Brake Pedal Position Sensor Signal Message Counter Incorrect

DTC P165C

Sensor Reference Voltage Status Message Counter Incorrect

DTC P167F

Battery Voltage Signal Message Counter Incorrect

DTC P16E8

Engine Controls Ignition Relay Signal Message Counter Incorrect

DTC P16FF

Engine Controls Ignition Relay Request Signal Message Counter Incorrect

DTC P175F

Acceleration Sensor Signal Message Counter Incorrect

DTC P1761

Up and Down Shift Switch Signal Message Counter Incorrect

DTC P1762

Transmission Mode Switch Signal Message Counter Incorrect

DTC P1775

Transmission Range Request Signal Message Counter Incorrect

DTC P179B

Transmission Range State Command Signal Message Counter Incorrect

DTC P189C

Transmission Range Command Message Performance

DTC P2544

Transmission Torque Request Signal Message Counter Incorrect

DTC P30B4

NOx Sensor 1 Signal Message Counter Incorrect

DTC P30B5

NOx Sensor 2 Signal Message Counter Incorrect

DTC P30BC

Particulate Matter Sensor Control Module Status Signal Message Counter Incorrect

DTC P30BD

Engine Stall Prevention Active Signal Message Counter Incorrect

DTC P30D5

NOx Sensor 3 Signal Message Counter Incorrect

DTC P30DE

Fuel Rail Pressure Sensor 2 Signal Message Counter Incorrect

DTC P3168

Fuel Injector Set 2 Commands Signal Message Counter Incorrect

DTC P3169

Fuel Injector Control Module Commands Signal Message Counter Incorrect

DTC P316B

Secondary Fuel System Requests Signal Message Counter Incorrect

Circuit/System Description

Control modules connected to the serial data circuits monitor the communication during normal vehicle operation. Operating information and commands are exchanged among the control modules. Each module on the serial data circuit maintains a transmit error counter and a receive error counter. The counter values increase with detected errors and decrease with error-free messages.

Conditions for Running the DTC

• Ignition=On - For greater than 3 s
• Serial Data=Enabled

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

Serial Data=Message Counter Incorrect - Control module that has set the DTC

The above condition(s) must occur 5 times.

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type C DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type C DTC

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition - On / Vehicle - In Service Mode

2. Verify there are no DTCs set related to the following system/component: Serial Data

• If a related DTC is set

Refer to: Diagnostic Trouble Code (DTC) List - Vehicle

• Go to next step: If a related DTC is not set

3. Clear the DTCs.

4. Operate the vehicle within the Conditions for Running the DTC.

Verify the DTC does not set.

• If the DTC sets

1. Ignition/Vehicle - Off
2. Replace the component:The control module that is sending the error message.
3. Operate the vehicle within the Conditions for Running the DTC.

Verify the DTC does not set.

• If the DTC sets

Replace the component: Control module that has set the DTC

• Go to next step: If the DTC does not set

4. All OK.

• Go to next step: If the DTC does not set

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification.

For control module replacement, programming, and setup refer to: Control Module References.

DTC P1007 or P129D

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P1007

Fuel Pump Driver Control Module Ignition On/Start Switch Circuit High Voltage

DTC P129D

Fuel Pump Driver Control Module Ignition On/Start Switch Circuit Low Voltage

Diagnostic Fault Information

Circuit/System Description

The fuel pump driver control module monitors the ignition voltage circuit in order to determine if the voltage is within the normal operating range.

Conditions for Running the DTC

• Engine is cranking or running
• The powertrain sensor relay is commanded ON

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P1007

• The fuel pump driver control module ignition switch circuit voltage is greater than a calibrated value for 1 s.
• Requires 40 failures out of 50 samples at 0.05 s per sample.

P129D

The fuel pump driver control module ignition switch circuit voltage is less than a calibrated value for 1 s.

Action Taken When the DTC Sets

DTC P1007 and P129D are Type B DTCs.

Conditions for Clearing the DTC

DTC P1007 and P129D are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify the engine cranks.

• If the engine does not crank

Refer to Starter Solenoid Does Not Click.

• Go to next step: If the engine cranks

2. Ignition ON.

3. Verify DTC P0562 or P0563 is not set.

• If DTC P0562 or P0563 is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: DTC P0562 or P0563 is not set

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

NOTE: Circuit/System Verification must be performed first or misdiagnosis may result.

1. Ignition OFF, all vehicle systems OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module. It may take up to 2 min for all vehicle systems to power down.

2. Ignition ON.

3. Verify a test lamp illuminates between the ignition circuit terminal 17 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF, remove the test lamp.
2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If the test lamp illuminates

4. Ignition OFF, and all vehicle systems OFF, it may take up to 2 min for all vehicle systems to power down.

5. Verify a test lamp does not illuminate between the ignition circuit terminal 17 and ground.

• If the test lamp illuminates

Repair the short to voltage on the circuit.

• Go to next step: If the test lamp does not illuminate

6. Replace the K111 Fuel Pump Driver Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Refer to Control Module References for control module replacement, programming and setup.

DTC P111E

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P111E

Engine Coolant Temperature Sensor Not Plausible

Diagnostic Fault Information

Typical Scan Tool Data

ECT Sensor Temperature

Circuit/System Description

The engine coolant temperature (ECT) sensor is a variable resistor that measures the temperature of the engine coolant. The engine control module (ECM) supplies 5V to the ECT sensor signal circuit and a ground for the low reference circuit.

If the ECM detects that the temperature difference between the measured and modeled ECT is not within an acceptable operating range of each other, then the ECM will continue to run this diagnostic to determine if a block heater was active during the engine OFF time.

Conditions for Running the DTC

• DTCs P0111, P0112, P0113, P0114, P0117, P0118, P0128, P0502, P0503, P0601, P1621, or P2610 are not set.
• The vehicle has had a minimum ignition OFF time of 8 hours.
• The engine is running.
• The start-up modeled ECT is colder than 50ºC (+122ºF).
• The previous accumulated MAF is greater than 6, 000 grams.
• The previous engine run time is greater than 600 seconds.

OR

• The vehicle has had a minimum ignition OFF time of 8 hours.
• The engine is running.
• The previous ECT at engine shutdown is warmer than 75ºC (+167ºF).
• The previous accumulated MAF is greater than 6, 000 grams.
• The previous engine run time is greater than 600 seconds.

This DTC runs continuously within the enabling conditions.

Conditions for Setting the DTC

P111E

The ECM detects a temperature difference at initial power-up that indicates that the actual measured ECT is 10ºC (18ºF) greater than the modeled ECT, and an active block heater has not been detected.

Action Taken When the DTC Sets

DTC P111E is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P111E is a Type B DTC.

Diagnostic Aids

• Engine coolant that is leaking through the sensor will create a high resistance short to ground.

  This condition results in less voltage on the ECT sensor signal circuit, which is interpreted by the ECM as a warmer ECT.

• The ECM memory which includes the ignition OFF timer is maintained by battery power. If the ECM or the battery are disconnected for less than 15 seconds the proper operation of the ECM memory and the timer can be disrupted. Always disconnect these components for greater than 30 seconds.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Turn OFF the ignition.

2. Inspect the cooling system surge tank for the proper engine coolant level.

3. If the ignition has been OFF for 8 hours or greater, the intake air temperature (IAT) sensor, the IAT sensor 2, and the ECT sensor should be within 9ºC (16ºF) of each other and also the ambient temperature. Ignition ON, observe the scan tool IAT Sensor, IAT Sensor 2 and the ECT Sensor parameters. Compare those sensor parameters to each other and also to the ambient temperature to determine if the ECT sensor is skewed warmer.

4. Engine running, observe the ECT Sensor parameter. The reading should be between -39 to +120ºC (-38 to +248ºF) depending on the current ambient temperature and the vehicle operating conditions.

5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset.

You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the B34 Engine Coolant Temperature Sensor harness connector at the sensor. It may take up to 2 minutes for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Verify the scan tool ECT Sensor parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF)

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance.
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module

• Go to next step: If colder than -39ºC (-38ºF)

5. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2.

6. Verify the scan tool ECT sensor parameter is warmer than 149ºC (300ºF).

• If warmer than 149ºC (300ºF)

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, Ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V

7. Test or replace the B34 engine coolant temperature sensor.

Component Testing

1. Ignition OFF, disconnect the harness connector at the B34 Engine Coolant Temperature Sensor.

2. Test the ECT sensor by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Engine Coolant Temperature Sensor table. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B34 Engine Coolant Temperature Sensor.

• Go to next step: If within the specified range

3. Test for infinite resistance between each terminal and the sensor housing.

• If less than infinite resistance

Replace the B34 Engine Coolant Temperature Sensor.

• Go to next step: If infinite resistance

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Engine Coolant Temperature Sensor Replacement
• Control Module References for ECM replacement, programming, and setup

DTC P1176 or P1177

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P1176

Fuel Pump Driver Control Module 5V Reference 1 Circuit

DTC P1177

Fuel Pump Driver Control Module 5V Reference 2 Circuit

Circuit/System Description

The Fuel Pump Driver Control Module has 2 internal 5V reference circuits. Each internal reference circuit provides external 5V reference circuits to one sensor. A short to ground or short to voltage on one external 5V reference circuit can affect the component connected to the same internal 5V reference circuit.

Conditions for Running the DTC

These DTCs run continuously when the ignition voltage is greater than 6.4 V.

Conditions for Setting the DTC

The Fuel Pump Driver Control Module detects a short to ground or voltage on any of the 5V reference circuits for greater than 0.5 s.

Action Taken When the DTC Sets

DTCs P1176, P1177 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P1176, P1177 are Type A DTCs.

Diagnostic Aids

P1176

The 5V reference 1 circuit provides 5 V circuits to the sensors listed below:

P1177

The 5V reference 2 circuit provides 5 V circuits to the sensors listed below:

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify scan tool 5V Reference 1-2 Circuit Status parameters do not display Malfunction.

• If any of the parameters display Malfunction

Refer to Circuit/System Testing.

• Go to next step: If none of the parameters display Malfunction

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

5. All OK.

Circuit/System Testing

NOTE: Additional DTCs will set when disconnecting the components.

1. Ignition OFF, disconnect the harness connector at all appropriate sensors for the applicable DTC.

Refer to Diagnostic Aids.

2. Ignition ON.

3. Test for 4.8 - 5.2 V between one of the 5V reference circuits and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connectors at the K111 Fuel Pump Driver Control Module.
2. Test for infinite resistance between the 5V reference circuit for each applicable component and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K111 Fuel Pump Driver Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connectors at the K111 Fuel Pump Driver Control Module.
2. Test for less than 1 V between the 5V reference circuit for each applicable component and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If between 4.8 - 5.2 V

NOTE: A short to voltage or ground on the signal circuit of certain components may cause this DTC to set.

4. Verify the appropriate scan tool 5V Reference 1, 2 Circuit Status parameter displays OK while connecting each component associated with the 5V reference circuit one at a time.

• If the parameter does not display OK when a component is connected

Test the signal circuit of that component for a short to ground or voltage. If the circuit tests normal, replace the component.

• Go to next step: If the parameter displays OK when all components are connected

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD)
• Control Module References for engine control module replacement, programming, and setup.

DTC P1178 or P1179

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for a overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P1178

Fuel Pump Driver Control Module Sensor 1 Internal Supply Circuit

DTC P1179

Fuel Pump Driver Control Module Sensor 2 Internal Supply Circuit

Circuit/System Description

The fuel pump power control module is in constant communication with the engine control module (ECM) regarding the operating state of the fuel pump power control system. Serial data messages are sent in a continuously repeating series of rolling counts with associated password protect samples. Each count/sample is assigned a value. When the ECM determines there is an error in the fuel pump control module fuel level sensor internal supply circuit, the ECM sets DTC P1178 or P1179.

Conditions for Running the DTC

• The ignition voltage is greater than 11 V.
• The DTC runs continuously when the above condition is met.

Conditions for Setting the DTC

The ECM detects an error value for over 1 s.

Action Taken When the DTC Sets

DTC P1178 and P1179 are Type A DTCs.

Conditions for Clearing the DTC

DTC P1178 and P1179 are Type A DTCs.

Diagnostic Aids

An intermittent fault in the CAN circuits will cause the ECM to set DTC P1178 or P1179.

Reference Information

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE:

• DTC P1178 and P1179 are informational DTCs.
• Diagnose all other engine control module DTCs prior to DTC P1178 or P1179.

1. Verify that no other DTCs are set except for DTC P1178 or P1179.

• If any other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If only DTC P1178 or P1179 is set

2. Replace the K111 Fuel Pump Power Control Module.

3. Verify the DTC does not set while operating the vehicle within the Conditions for Running the DTC.

• If DTC sets

Replace the K20 Engine Control Module.

• Go to next step: If DTC does not set

4. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD) for K111 Fuel Pump Power Control Module Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P1255

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P1255

Fuel Pump Control Module Driver High Temperature

Circuit/System Description

The engine control module (ECM) supplies voltage to the fuel pump driver control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump driver control module remains active for 2 seconds, unless the engine is in crank or run. While this voltage is being received, the fuel pump driver control module supplies a varying voltage to the fuel tank fuel pump module in order to maintain the desired fuel pressure.

Conditions for Running the DTC

• The ignition voltage is between 7 - 32 V.
• The engine is cranking or running.
• The fuel pump enable circuit is commanded ON.
• The DTC runs continuously when the conditions above are met.

Conditions for Setting the DTC

The fuel pump driver control module detects a driver temperature greater than 302ºF (150ºC) for less than 0.5 s.

Action Taken When the DTC Sets

DTC P1255 is a Type A DTC.

Conditions for Clearing the DTC

DTC P1255 is a Type A DTC.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0231, P0232, or P023F is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

3. Verify that the area where the K111 Fuel Pump Driver Control Module is located is free of debris, clutter, or any insulating material that would cause the fuel pump driver control module to overheat.

• If any debris, clutter, or other material is found

1. Clear the area where the K111 Fuel Pump Driver Control Module is located.
2. Clear the DTC and test drive the vehicle.
3. Verify DTC P1255 is not set.
   • If DTC P1255 is set, replace the K111 Fuel Pump Driver Control Module.
   • Go to next step: If DTC P1255 is not set
4. All OK.

• Go to next step: If no debris, clutter, or other material is found

4. Clear the DTC and test drive the vehicle.

5. Verify DTC P1255 is not set.

• If DTC P1255 is set

Replace the K111 Fuel Pump Driver Control Module.

• Go to next step: If DTC P1255 is not set.

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD).

DTC P127C, P128A, P128B, P16E4, or P16E5

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P127C

Fuel Rail Pressure Sensor 2 Circuit Low Voltage

DTC P128A

Fuel Rail Pressure Sensor 1 Internal Performance

DTC P128B

Fuel Rail Pressure Sensor 2 Internal Performance

DTC P16E4

Sensor Communication Circuit 3 Low Voltage

DTC P16E5

Sensor Communication Circuit 3 High Voltage

Diagnostic Fault Information

Typical Scan Tool Data

Fuel Rail Pressure Sensor

Fuel Rail Pressure Sensor 2

Circuit/System Description

The fuel rail pressure sensor transmits fuel pressure and temperature information by serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The fuel rail pressure sensor internal microprocessor allows 4 separate sensor outputs from one 3 wire sensor. The engine control module (ECM) supplies the fuel rail pressure sensor with a 5 V reference circuit, a low reference circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the fuel rail pressure sensor to the ECM. The ECM decodes the serial data signal into separate voltages which are displayed on a scan tool as the voltage inputs from the Fuel Temperature Sensor, Fuel Rail Pressure Sensor and Fuel Rail Pressure Sensor 2.

Conditions for Running the DTC

P128A or P128B

• DTC P128F, P16E4 or P16E5 is not set.
• Ignition is ON.
• The DTCs run continuously when the above condition are met.

P127C, P16E4 or P16E5

• Ignition is ON.
• No DTC clear code
• The DTCs run continuously when the above condition are met.

Conditions for Setting the DTC

P127C

The engine control module detects the fuel pressure sensor 2 SENT digital read value is less than or equal to 94 for greater than 1 s.

P128A

The engine control module detects fuel pressure sensor 1 SENT digital read value is greater than 4, 089 for greater than 1 s

P128B

The engine control module detects fuel pressure sensor 2 SENT digital read value is greater than 4, 089 for greater than 1 s

P16E4

The engine control module detects fuel pressure sensor SENT signal shorted low for greater than 1 s

P16E5

The engine control module detects fuel pressure sensor SENT signal shorted high for greater than 1 s

Action Taken When the DTC Sets

DTCs P127C, P128A, P128B, P16E4 and P16E5 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P127C, P128A, P128B, P16E4 and P16E5 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the fuel rail pressure sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON/Vehicle in Service Mode.

2. Verify that DTC P0641, P0651, P0697, P06A3, or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Verify that DTC P0182, P0183, P0187, P0188, P111F, P126E, P126F, P128A, or P128B are not set.

• If DTC P128A or P128B are the only DTCs set

Test or replace the B310 Fuel Pressure/Temperature Sensor.

• If DTC P0183, P0184, P0187, P0188, P111F, P126E, P126F, P127C, P16E4, or P16E5 is set with any of the DTCs

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

NOTE: Disconnecting the fuel rail pressure sensor harness connector causes additional DTCs to set.

1. Ignition/Vehicle OFF, and all vehicle systems OFF, disconnect the harness connector at B310 Fuel Pressure/Temperature Sensor. It may take up to 2 min for all vehicle systems to power down.

2. Test for less than 5 Ω between the low reference circuit terminal 1 and ground.

• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 3 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Test for 4.8 - 5.2 V between the signal circuit terminal 2 and ground.

• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Replace the B310 Fuel Pressure/Temperature Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Injection Fuel Rail Fuel Pressure Sensor Replacement for B310 Fuel Pressure/Temperature Sensor.
• Control Module References for control module replacement, programming, and setup.

DTC P12A6

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P12A6

Fuel Pump Driver Control Module Enable Circuit Performance

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) provides ignition voltage to the fuel pump driver control module whenever the engine is cranking or running. The control module enables the fuel pump driver control module as long as the engine is cranking or running, and ignition system reference pulses are received.

While this enable voltage is being received, the fuel pump driver control module supplies a varying voltage to the in-tank fuel pump module in order to maintain the desired fuel line pressure.

Conditions for Running the DTC

• The ignition voltage is greater than 7 V.
• The DTC runs continuously when the condition above is met.

Conditions for Setting the DTC

The ECM state of the fuel pump enable circuit does not match the state of the fuel pump enable circuit sensed by the fuel pump driver control module for 0.5 s.

Action Taken When the DTC Sets

DTC P12A6 is a Type A DTC.

Conditions for Clearing the DTC

DTC P12A6 is a Type A DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify that DTC P12A6 is not set.

• If the DTC is set

Refer to Circuit/System Testing.

• Go to next step: If the DTC is not set

3. Verify the parameters listed below do not display Malfunction when commanding the Fuel Pump Enable On and Off with a scan tool.

• Fuel Pump Enable Circuit Low Voltage Test Status
• Fuel Pump Enable Circuit Open Test Status
• Fuel Pump Enable Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.

2. Ignition ON for 10 s.

3. Verify that a test lamp does not illuminate between the control circuit terminal 2 and ground.

• If the test lamp illuminates

1. Ignition OFF, remove the test lamp, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

4. Remove the test lamp.

5. Verify the scan tool Fuel Pump Enable Circuit Low Voltage Test Status parameter is OK when commanding the Fuel Pump Enable On with a scan tool.

• If OK is not displayed

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If OK is displayed

6. Install a 3 A fused jumper wire between the control circuit terminal 2 and ground.

7. Verify the scan tool Fuel Pump Enable Circuit Low Voltage Test Status parameter is Malfunction when commanding the Fuel Pump Enable On with a scan tool.

If Malfunction is not displayed

1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

Go to next step: If Malfunction is displayed

8. Replace the K111 Fuel Pump Driver Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Pump Power Control Module Replacement (AWD) or Fuel Pump Power Control Module Replacement (FWD)
• Control Module References for ECM replacement, setup, and programming

DTC P135A

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P135A

Ignition Coil Supply Voltage Circuit Bank 1

Diagnostic Fault Information

Circuit/System Description

The ignition system uses an individual ignition coil for each cylinder. The engine control module (ECM) monitors the ignition voltage from the fuse to the individual coils.

Conditions for Running the DTC

• Delay starting at ignition On for 5 engine revolutions.
• Ignition Run/Crank relay voltage is greater than 5 V
• PT relay voltage is greater than 11 V

The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects less than 2.5 V on the ignition coil supply voltage circuit.

Action Taken When the DTC Sets

DTC P135A is a Type B DTC.

Conditions for Clearing the DTC

DTC P135A is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Electronic Ignition System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References

Circuit/System Verification

1. Ignition ON.

2. Verify the scan tool Ignition Coil Supply Voltage parameter displays ON.

• If ON is not displayed

Refer to Circuit/System Testing.

• Go to next step: If ON is displayed

3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

5. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module.

2. Connect a 3 A fused jumper wire between the control circuit terminal 67 and ground, ignition ON.

3. Verify a test lamp illuminates between the ignition circuit terminal 51 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF, remove the test lamp.
2. Test for less than 2 Ω in the ignition circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

NOTE: The ignition circuit may supply voltage to other components.

Make sure to test all circuits and components for a short to ground that share the ignition circuit.

1. Ignition OFF, remove the test lamp, and disconnect all components on the circuit.
2. Test for infinite resistance between the ignition circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Replace the fuse, ignition ON.
4. Verify the fuse is good after connecting each of the components one at a time.
   • If the fuse opens, replace the component that opens the fuse when connected.
   • If the fuse is good, all OK.

• Go to next step: If the test lamp illuminates

4. Replace the K20 Engine Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Ignition Coil Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P1400

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptor

DTC P1400

Cold Start Emission Reduction Control System

Circuit/System Description

The catalyst must be warmed to efficiently reduce the emissions. The cold start strategy is to reduce the amount of time it takes to warm the catalyst. During a cold start, the engine spark timing is altered to allow the catalyst to warm quickly. This diagnostic monitors the following to build an exhaust energy model:

• Spark advance
• Engine airflow
• Engine coolant temperature
• Engine run time

The actual model is then compared to the expected exhaust energy model.

Conditions for Running the DTC

• DTCs P0101, P0102, P0103, P0106, P0107, P0108, P0112, P0113, P0114, P0116, P0117, P0118, P0121, P0122, P0123, P0201, P0202, P0203, P0204, P0222, P0223, P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0351, P0352, P0353, P0354, P0641, P0651, P0697, P06A3, P2122, P2123, P2127, P2128, P2135, and P2138 are not set.
• The engine coolant temperature (ECT) is between -12 to +56ºC (10 - 132ºF).
• The calculated 3-way catalyst temperature is colder than 500ºC (932ºF).
• The barometric (BARO) pressure is greater than 75 kPa.
• The engine control module (ECM) will exit the diagnostic if the calculated 3-way catalyst temperature is greater than 1, 000ºC (1832ºF) when the engine run time is greater than 17 s.
• Vehicle speed is less than 1.6 km/h (1 mph).
• The accelerator pedal is not depressed.
• The ECM will exit the diagnostic if the engine run time is greater than a calibrated value.
• This DTC runs within the first 15 s of start-up. This diagnostic runs once per trip when a cold start has been determined.

Conditions for Setting the DTC

The actual exhaust energy model does not match the expected exhaust energy model.

Action Taken When the DTC Sets

DTC P1400 is a Type A DTC.

Conditions for Clearing the DTC

DTC P1400 is a Type A DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Vehicle OFF, allow the engine to cool to be within the temperatures listed in the Conditions for Running the DTC.

2. Engine running.

3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset.

You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

4. Verify the DTC does not set.

• If the DTC sets

1. Verify that none of the conditions listed below exists with the air intake system:
   • Damage, restriction, or modification
   • Dirty or deteriorating air filter element
   • Crankcase ventilation system for correct operation
   • Water intrusion
   • Vacuum leak and other unmetered air downstream of the mass air flow (MAF) sensor
   • Intake manifold leak
   • If any of the conditions exist

     Repair as necessary.

   • Go to next step: If none of the conditions exist
2. Verify that none of the conditions listed below exists with the exhaust system:
   • Exhaust leak
   • Damaged, restricted, or modified exhaust system - Refer to Symptoms - Engine Exhaust.
   • If any of the above conditions exist

     Repair as necessary.

   • Go to next step: If none of the conditions exist
3. If all of the above conditions test normal, inspect for an engine mechanical condition that could alter the air flow into the combustion chamber. Refer to Symptoms - Engine Mechanical.

• Go to next step: If the DTC does not set

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

DTC P1516, P2101, P2119, or P2176

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P1516

Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance

DTC P2101

Throttle Actuator Position Performance

DTC P2119

Throttle Closed Position Performance

DTC P2176

Minimum Throttle Position Not Learned

Diagnostic Fault Information

Circuit/System Description

The Throttle Body Assembly contains a contact-less inductive throttle position sensing element that is managed by a customized integrated circuit. The throttle position sensor is mounted within the Throttle Body Assembly and is not serviceable. The Engine Control Module (ECM) supplies the throttle body with a 5 V reference circuit, a low reference circuit, an H-bridge motor directional control circuit, and an asynchronous signal/serial data circuit. The asynchronous signal means communication is only going from the throttle body to the ECM. The throttle body cannot receive data from the ECM over the signal/serial data circuit. The throttle position sensor provides a signal voltage that changes relative to throttle blade angle. The customized integrated circuit translates the voltage based position information into serial data using the Society of Automotive Engineers (SAE) J2716 Single Edge Nibble Transmission (SENT) protocol. The throttle position sensor information is transmitted between the throttle body and the ECM on the signal/serial data circuit. The ECM decodes the serial data into a representation of voltage signals that are occurring in the throttle body. The information is then displayed on a scan tool as the voltage inputs from TP sensors 1 and 2.

The ECM controls the throttle valve by applying a varying voltage to the control circuits of the throttle actuator control (TAC) motor. The ECM monitors the duty cycle that is required to actuate the throttle valve. The ECM monitors the throttle position sensor signal/serial data circuit to determine the actual throttle valve position.

Conditions for Running the DTC

P1516

• DTC P0606, P1682 is not set.
• The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
• DTC P1516 runs continuously when the above conditions are met.

P2101

• DTC P0606, P1682 is not set.
• The run/crank or powertrain relay voltage is greater than 6.41 V and reduced power is not active.
• The engine is running or the following conditions are met:
  • The engine is not running.
  • The ignition voltage is greater than 11 V.
  • The TAC system is not in the Battery Saver mode.
  • The ECM is commanding the throttle.
  • The ECM has learned the minimum throttle position.
• DTC P2101 runs continuously when the above conditions are met.

P2119

• DTCs P0122, P0123, P0222, P0223, or P06A3 is not set.
• The run/crank or powertrain relay voltage is greater than 5.5 V and reduced power is not active.
• The system is not in the Battery Save mode.
• The ECM is not commanding the throttle.
• DTC P2119 runs continuously when the above conditions are met.

P2176

• The run/crank or powertrain relay voltage is greater than 6.4 V and reduced power is not active.
• DTC P2176 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P1516

The ECM detects an unstable throttle position for greater than 1 s.

P2101

• The ECM detects the actual throttle position does not match the predicted throttle position for greater than 1 s.

  OR

• The ECM detects the throttle control is driving the throttle in the incorrect direction or exceed the reduced power limit.

P2119

The ECM determines that the throttle blade did not return to the rest position within 1 s.

P2176

The ECM detects that both throttle position sensors were greater than a predetermined voltage during the minimum throttle learn procedure for greater than 2 s.

Action Taken When the DTC Sets

• DTC P1516 is a Type B DTC.
• DTCs P2101 and P2176 are Type A DTCs.
• DTC P2119 is a Type C DTC.
• The ECM commands the TAC system to operate in the Reduced Engine Power mode.
• A message center or an indicator displays Reduced Engine Power.
• Under certain conditions, the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

• DTC P1516 is a Type B DTC.
• DTCs P2101 and P2176 are Type A DTCs.
• DTC P2119 is a Type C DTC.

Diagnostic Aids

• Depending on the Start Up ECT, the Desired Throttle Position percentage maybe greater or less than the Throttle Position with the TAC motor at rest. When the ignition is initially turned ON, or when the engine is cranking or running the Desired and Actual Throttle positions should closely match.
• Inspect for a condition in which the throttle valve may have been held open. For example, ice may have formed in the throttle bore causing the throttle valve not to close.
• A high resistance condition on the throttle position and throttle actuator control circuits could cause a DTC to set.
• A low battery condition may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

NOTE: A low battery voltage or charging system condition may cause a DTC to set.

2. Verify DTC P0121, P0122, P0123, P0222, P0223, P0562, P0621, P0622, or P2135 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Verify the scan tool Throttle Body Idle Air flow Compensation parameter is less than 90 %.

• If 90 % or greater

Refer to Throttle Body Cleaning.

• Go to next step: If less than 90 %

4. Clear the DTCs with a scan tool.

5. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.

6. Ignition ON.

7. Verify the scan tool TAC Motor parameter displays Enabled while slowly depressing the accelerator pedal.

• If Enabled is not displayed

Refer to Circuit/System Testing.

• Go to next step: If Enabled is displayed

8. Verify DTC P1516, P2101, P2119, or P2176 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

NOTE: If there is a condition with the throttle body, the TAC Motor Command parameter will go to 99 % for a predetermined amount of time and then a DTC sets. Once a DTC is set, the TAC Motor Command parameter will go to 0 % and the TAC Motor parameter will display Disabled.

9. Verify the scan tool TAC Motor parameter displays Enabled while performing the Throttle Sweep Test with a scan tool.

• If Enabled is not displayed

Test or replace the Q38 Throttle Body Assembly.

• Go to next step: If Enabled is displayed

10. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

11. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

12. All OK.

Circuit/System Testing

1. Ignition OFF.

WARNING: Turn OFF the ignition before inserting fingers into the throttle bore.

Unexpected movement of the throttle blade could cause personal injury.

2. Verify the conditions listed below do not exist with the Q38 Throttle Body:

NOTE:

• The rest position is defined as the actual Throttle Position percentage when the ignition is OFF or with the ignition ON for greater than 30 seconds.
• When the ignition is OFF, spring tension should hold the throttle plate in the rest position. You should be able to open the throttle plate to wide open throttle (WOT) or push the throttle plate to the fully closed position. In each case, the throttle plate should return to the rest position without assistance.

• A throttle blade that is not in the rest position
• A throttle blade that is binding open or closed
• A throttle blade that is free to move open or closed without spring pressure
• If a condition is found

Replace the Q38 Throttle Body.

• Go to next step: If a condition is not found

NOTE: Disconnecting the throttle body harness connector may cause additional DTCs to set.

3. Disconnect the harness connector at the Q38 Throttle Body Assembly, ignition ON.

NOTE: The test lamp may illuminate briefly when the ignition switch is turned on, but should not remain illuminated.

4. Verify that a test lamp does Not illuminate continuously between each motor control circuit listed below and ground.

• TAC Motor Control Closed circuit terminal 1
• TAC Motor Control Open circuit terminal 2
• If the test lamp is always ON

1. Ignition OFF, disconnect the harness connector X2 at the K20 Engine Control Module, ignition ON
2. Test for less than 1 V between the motor control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp is always OFF

5. Verify that a test lamp does not illuminate between each motor control circuit listed below and B+.

• TAC Motor Control Closed circuit terminal 1
• TAC Motor Control Open circuit terminal 2
• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector X2 at the K20 Engine Control Module.
2. Test for infinite resistance between the control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

6. Ignition OFF, set the DMM to the 40 V scale, select the Min/Max Recording Mode, and set the Peak Min/Max response time to 1 ms.

NOTE:

• The test lamp must be connected to circuit before turning ignition on or incorrect diagnosis may occur.
• The ignition must be OFF and the ECM completely powered down before testing each circuit or a lower voltage will be recorded. It may take up to 2 min for all vehicle systems to power down.
• The DMM Min/Max Recording Mode and the response time of 1 ms must be reset after testing each circuit or a lower voltage will be recorded.

7. Verify the Max voltage is within 3 V of B+ while using DMM Min/Max Recording Mode function on each control circuit listed below as the ignition is turned ON.

• TAC Motor Control Closed circuit terminal 1
• TAC Motor Control Open circuit terminal 2
• If not within 3 V of B+

1. Ignition OFF, disconnect the harness connector X2 at the K20 Engine Control Module.
2. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If within 3 V of B+

8. Replace the Q38 Throttle Body.

Repair Instructions

• Throttle Body Assembly Replacement
• Control Module References for ECM replacement, programming, and setup

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.

5. Ignition ON.

6. Verify the scan tool TAC Motor parameter displays Enabled while performing the Throttle Sweep Test with a scan tool.

• If Enabled is not displayed

Test or replace the Q38 Throttle Body Assembly.

• Go to next step: If Enabled is displayed

7. If the repair was related to a DTC, duplicate the Conditions for Running the DTC and use the Freeze Frame/Failure Records, if applicable, in order to verify the DTC does not set.

• If DTC sets

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If DTC does not set

8. All OK.

DTC P157A

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P157A

Sensor Supply Voltage Relay Feedback Circuit High Voltage

Circuit/System Description

There is 1 Sensor Supply Voltage Relay Feedback circuit supplied to the K111 Fuel Pump Driver Control Module from the K20 Engine Control Module.

Conditions for Running the DTC

P157A

The DTC runs continuously when Ignition OFF.

Conditions for Setting the DTC

P157A

The ECM detects that the voltage level difference is greater than 11 V between the Wake Up/Enable Voltage and battery supply voltage circuits for greater than 1 s.

Action Taken When the DTC Sets

DTC P157A is a Type B DTC.

Conditions for Clearing the DTC

DTC P157A is a Type B DTC.

Diagnostic Aids

The sensor bus relay may also be labeled the sensor supply voltage relay, sensor bus relay control circuit, or sensor supply voltage feedback circuit.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LGX)
• Power Distribution Wiring Schematics

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Electrical Center Identification Views
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: An open on this circuit may cause DTC U18A2 to set. If any other DTC is set, diagnose that DTC first.

1. Ignition ON, observe the scan tool DTC information. Verify DTC P157A is not set.

• If DTC P157A is set

Refer to Circuit/System Testing.

• Go to next step: If DTC P157A is set

2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

3. All OK.

Circuit/System Testing

1. Ignition Off, disconnect the harness connector at the K111 Fuel Pump Driver Control Module.

2. Ignition On.

3. Test for greater than 11 V between control circuit terminal 2 at the K111 Fuel Pump Driver Control Module harness connector and ground.

• If 11 V or greater

Replace the K111 Fuel Pump Driver Control Module

• Go to next step: If less than 11 V

4. Ignition Off, disconnect the harness connector: X3 at the K20 Engine Control Module.

5. Test for less than 1 V between control circuit terminal 2 at the K111 Fuel Pump Driver Control Module harness connector and ground.

• If 1 V or greater, repair the short to voltage on the circuit
• Go to next step: If less than 1 V

6. Test for infinite resistance between control circuit terminal 2 at the K111 Fuel Pump Driver Control Module harness connector and ground.

• If less than infinite resistance, repair the short to ground on the circuit
• Go to next step: If infinite resistance

7. Test for less than 2 Ω between test points: terminal X3-3 at the Engine Control Module harness and terminal 2 at the K111 Fuel Pump Driver Control Module harness.

• If 2 Ω or greater, repair the open/high resistance in the circuit
• Go to next step: If less than 2 Ω

Go to next step: Replace the K20 Engine Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Engine Wiring Harness Junction Block Replacement (LTG) or Engine Wiring Harness Junction Block Replacement (LGX).
• Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center)
• Control Module References for engine control module replacement, programming, and setup.

DTC P163A

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P163A

Control Module Fuel Pressure Regulator 1 Control System Circuitry Performance

Circuit/System Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM) or an out of range high pressure fuel pump actuator current.

Conditions for Running the DTC

• DTC P0016, P0017, P0090, P0091, P0092, P00C8, P00C9, P00CA, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0128, P0191, P0192, P0193, P0335, P0336, P0340, P0341, P0365, P0366, P0628, or P1682 is not set.
• The engine is running.
• The ignition voltage is greater than 11 V.
• The low side fuel pressure is greater than 250 kPa (36 psi).
• The barometric (BARO) pressure is greater than 70 kPa.
• The intake air temperature (IAT) is warmer than -20ºC (-4ºF).
• DTC P163A runs continuously when the conditions are met for greater than 500 mS.

Conditions for Setting the DTC

The ECM detects a condition with the integrated circuits of the high pressure fuel pump actuator driver module or the ECM detects that the current used to drive the high pressure fuel pump actuator is greater than 11 A or less than 0.1 A for greater than 4 s.

Action Taken When the DTC Sets

DTC P163A is a Type B DTC.

Conditions for Clearing the DTC

DTC P163A is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the G18 High Pressure Fuel Pump.

NOTE: The DMM and test leads must be calibrated to 0 Ω in order to prevent misdiagnosis.

2. Test for 0.3 - 0.7 Ω at 20ºC (68ºF) between the high control circuit terminal 1 and the low control circuit terminal 2 on the G18 High Pressure Fuel Pump.

• If not between 0.3 - 0.7 Ω

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If between 0.3 - 0.7 Ω

3. Test for infinite resistance between each terminal on the G18 High Pressure Fuel Pump and the G18 High Pressure Fuel Pump housing.

• If less than infinite resistance

Replace the G18 High Pressure Fuel Pump.

• Go to next step: If infinite resistance

4. Ignition ON, verify that a test lamp does not illuminate between the high control circuit terminal 1 and ground and the low control circuit terminal 2 and ground at the ECM side of the harness connector.

• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector at the ECM, ignition ON.
2. Test for less than 1 V between the appropriate control circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

5. Verify that a test lamp does not illuminate between the high control circuit terminal 1 and B+ and the low control circuit terminal 2 and B+.

• If the test lamp illuminates

1. Ignition OFF, disconnect the harness connector at the ECM.
2. Test for infinite resistance between the appropriate control circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

6. Connect a 3 A fused jumper wire between the high control circuit terminal 1 and ground.

7. Verify the Fuel Pressure Regulator High Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator High Control Circuit Low Voltage Test Status transitions from OK to Malfunction.

• The parameters do not change

1. Ignition OFF, disconnect the harness connector at the ECM.
2. Test for less than 2 Ω in the high control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: The parameters change

8. Connect a 3 A fused jumper wire between the low control circuit terminal 2 and B+.

9. Verify the Fuel Pressure Regulator Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator Control Circuit High Voltage Test Status transitions from OK to Malfunction.

• The parameters do not change

1. Ignition OFF, disconnect the harness connector at the ECM.
2. Test for less than 2 Ω in the low control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: The parameters change

Go to next step: Replace the K20 Engine Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Pump Replacement
• Control Module References for engine control module replacement, setup, and programming
• Perform the Fuel Rail Pressure Relief Valve Reset procedure, if supported on the scan tool.

DTC P16A7, P16AF, or P16B3

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P16A7

Engine Controls Ignition Relay Feedback Circuit 2

DTC P16AF

Engine Controls Ignition Relay Feedback Circuit 2 Low Voltage

DTC P16B3

Engine Controls Ignition Relay Feedback Circuit 2 High Voltage

Diagnostic Fault Information

Engine Controls Ignition Relay

Typical Scan Tool Data

Engine Controls Ignition Relay Control Circuit Low Voltage, Open, and High Voltage Test Status - Component Commanded OFF

Engine Controls Ignition Relay Control Circuit Low Voltage, Open, and High Voltage Test Status - Component Commanded ON

Circuit/System Description

There are 3 ignition voltage circuits supplied to the engine control module (ECM). Two are supplied by the engine controls ignition relay, and the other is supplied by the ignition main relay. The ECM monitors and compares the ignition voltage supplied by the 2 relays.

Conditions for Running the DTC

P16A7

• The engine controls ignition relay is commanded ON.
• Ignition voltage is greater than 5.5 V.
• The DTC runs continuously when the above conditions are met.

P16AF

• The engine controls ignition relay is commanded ON.
• Ignition 1 signal voltage is greater than 11 V.
• The DTC runs continuously when the above conditions are met.

P16B3

The DTC runs when the engine controls ignition relay is commanded OFF.

Conditions for Setting the DTC

P16A7

The ECM detects that the voltage level difference is greater than 3 V between the engine controls ignition relay feedback circuit 2 and the ignition 1 signal circuit for greater than 1 s.

P16AF

The ECM detects the engine controls ignition relay feedback circuit 2 is less than 5 V.

P16B3

The ECM detects the engine controls ignition relay feedback circuit 2 is greater than 4 V for greater than 5 s.

Action Taken When the DTC Sets

• DTC P16A7 is a Type A DTC.
• DTC P16AF is a Type C DTC.
• DTC P16B3 is a Type B DTC.

Conditions for Clearing the DTC

• DTC P16A7 is a Type A DTC.
• DTC P16AF is a Type C DTC.
• DTC P16B3 is a Type B DTC.

Diagnostic Aids

The engine controls ignition relay may also be labeled the powertrain relay, the engine control module relay, or the main relay. The ignition main relay may also be labeled the run/crank relay, the ignition run relay, the ignition 1 relay, or the ignition relay.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LTG)
• Power Distribution Wiring Schematics

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Electrical Center Identification Views
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: A short to voltage on other components may cause DTC P16B3 to set. If any other DTC is set, diagnose that DTC first.

If you were sent here from Engine Cranks But Does Not Run, proceed to Circuit/System Testing.

1. Ignition ON, observe the scan tool DTC information. Verify DTC P16A7, P16AF, or P16B3 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

3. All OK.

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing unless sent here from Engine Cranks But Does Not Run.

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.

2. Verify a test lamp illuminates between ground and the B+ terminals listed below:

• Terminal 85
• Terminal 30
• If the test lamp does not illuminate

Replace the front compartment fuse block.

• Go to next step: If the test lamp illuminates

NOTE:

• Go to next step: High resistance in the circuit/underhood fuse block for either the KR75 Engine Controls Ignition Relay or the KR73 Ignition Main Relay can cause DTC P16A7 to set.
• Go to next step: A short to voltage on any of the circuits supplied by the engine controls ignition relay can cause DTC P16B3 to set.

3. Ignition ON.

4. Verify that a test lamp does not illuminate between the ignition voltage circuit terminal 87 and ground.

• If the test lamp illuminates

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module.
2. Ignition ON.
3. Test for less than 1 V between ground and connector terminal 73.
   • If 1 V or greater, repair the short to voltage in the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If the test lamp does not illuminate

5. Ignition OFF, connect a 20 A fused jumper wire between the B+ circuit terminal 30 and the ignition voltage circuit terminal 87.

6. Ignition ON.

7. Verify the scan tool Engine Controls Ignition Relay Feedback Signal parameter displays B+.

• If B+ is not displayed

1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module
2. Test for less than 2 Ω in the relay switch ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω
3. Test for infinite resistance between the relay switch ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If B+ is displayed

8. Ignition OFF, connect a DMM, set to the diode setting, between control circuit terminal 86 and ground.

9. Verify the DMM displays OL.

• If OL is not displayed

1. Disconnect the X1 harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between ground and the relay control circuit.
   • If less than infinite resistance, repair the short to ground in the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If OL is displayed

10. Ignition ON.

11. Verify the DMM displays less than 1 V.

• If 1 V or greater

1. Ignition OFF, disconnect the X1 connector at the K20 Engine Control Module.
2. Ignition ON.
3. Test for less than 1 V on the relay control circuit.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
4. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • if less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 1 V

12. Test or replace the KR75 Engine Controls Ignition Relay.

Component Testing

Relay Test

1. Ignition OFF, disconnect the KR75 Engine Controls Ignition Relay.

2. Test for 70 - 110 Ω between terminals 85 and 86:

• If less than 70 Ω or greater than 110 Ω

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If between 70 - 110 Ω

3. Test for infinite resistance between the terminals listed below:

• 30 and 86
• 30 and 87
• 30 and 85
• 85 and 87
• If less than infinite resistance

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If infinite resistance

4. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground.

5. Test for less than 2 Ω between terminals 30 and 87.

• If 2 Ω or greater

Replace the KR75 Engine Controls Ignition Relay.

• Go to next step: If less than 2 Ω

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center)
• Control Module References for engine control module replacement, programming, and setup.

DTC P16D7-P16D9

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P16D7

Sensor Bus Relay Control Circuit

DTC P16D8

Sensor Bus Relay Control Circuit Low

DTC P16D9

Sensor Bus Relay Control Circuit High

Diagnostic Fault Information

Engine Controls Ignition Relay

Circuit/System Description

There is 1 Sensor Supply Voltage Relay Feedback circuit supplied to the K111 Fuel Pump Driver Control Module from the K20 Engine Control Module.

Conditions for Running the DTC

P16D7

• The sensor bus relay is commanded ON.
• Battery supply signal voltage is less than 11 V.
• The DTC runs continuously when the above conditions are met.

P16D8

• The sensor bus relay is commanded ON.
• Battery supply signal voltage is less than 11 V.
• The DTC runs continuously when the above conditions are met.

P16D9

• The sensor bus relay is commanded OFF.
• Battery supply signal voltage is greater than 11 V.
• The DTC runs continuously when the above conditions are met.

Conditions for Setting the DTC

Control Circuit=Commanded state does not match the actual state for greater than 1 s

Action Taken When the DTC Sets

DTCs P16D7, P16D8 and P16D9 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P16D7, P16D8 and P16D9 are Type B DTCs.

Diagnostic Aids

The sensor bus relay may also be labeled the sensor supply voltage relay, sensor bus relay control circuit, or sensor supply voltage feedback circuit.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LGX)
• Power Distribution Wiring Schematics

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Electrical Center Identification Views
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool DTC information. Verify DTC P16D7, P16D8, or P16D9 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing.

• Go to next step: If none of the DTCs are set

2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

3. All OK.

Circuit/System Testing

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the electrical connector:K111 Fuel Pump Driver Control Module.

3. Verify a test lamp does not turn On between the test points:Control circuit terminal 2 & B+ terminal 7.

• If the test lamp turns On

1. Remove - Test Lamp
2. Disconnect the electrical connector:X3@ Verify a test lamp does not turn On between the test points: Control circuit terminal 2 & B+ terminal 7
   • If the test lamp turns On - Repair the short to ground on the circuit.
   • Replace the component: - K20 Engine Control Module

• Go to next step: If the test lamp does not turn On

4. Ignition - On / Vehicle - In Service Mode.

5. Verify a test lamp does not turn On between the test points: Control circuit terminal 2 & Ground terminal 22.

• If the test lamp turns On

1. Remove - Test Lamp
2. Disconnect the electrical connector:X3@K20 Engine Control Module
3. Verify a test lamp does not turn On between the test points:Control circuit terminal 2 & Ground terminal 22
   • If the test lamp turns On - Repair the short to voltage on the circuit.
   • If the test lamp does not turn On - Replace the component:K20 Engine Control Module

• Go to next step: If the test lamp does not turn On

6. Verify a test lamp turns On between the test points: Control circuit terminal 2 & B+ terminal 7

• If the test lamp does not turn On

1. Disconnect the electrical connector:X3@K20 Engine Control Module
2. Test for less than 2 ohms between the test points:Control circuit terminal 2@K111 Fuel Pump Driver Control Module & Control circuit terminal 3 X3@K20 Engine Control Module
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component:K20 Engine Control Module

• Go to next step: If the test lamp turns On

7. Replace the component: - K111 Fuel Pump Driver Control Module

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Engine Wiring Harness Junction Block Replacement (LTG) or Engine Wiring Harness Junction Block Replacement (LGX).
• Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center)
• Control Module References for engine control module replacement, programming, and setup.

DTC P2096 or P2097

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2096

Post Catalyst Fuel Trim System Low Limit

DTC P2097

Post Catalyst Fuel Trim System High Limit

Circuit Description

Fuel trim bias is used to keep the post catalyst air/fuel ratio within a predetermined range. This allows optimal catalyst efficiency under various operating conditions. The engine control module (ECM) constantly monitors how lean or rich the fuel trim bias is commanded, to determine if the fuel trim bias is greater than a calibrated amount.

Conditions for Running the DTC

• DTC P0016, P0017, P0030, P0036, P0053, P0054, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0116, P0117, P0118, P0119, P0128, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P015A, P015B, P0178, P0179, P0201, P0202, P0203, P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P0340, P0341, P0365, P0366, P0411, P0442, P0443, P0446, P0449, P0452, P0453, P0455, P0458, P0459, P0496, P0498, P0499, P111E, P1133, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157, P219A, P2227, P2228, P2229, P2230, P2269, P2270, P2271, P2440, P2444, or P2A00 is not set.
• The barometric pressure (BARO) is greater than 70 kPa (10.2 PSI).
• The manifold absolute pressure (MAP) is between 0 - 200 kPa (0 - 29 PSI).
• The intake air temperature (IAT) is between - 20ºC and +200ºC (-4 and +392ºF).
• The start up engine coolant temperature is warmer than - 20ºC (- 4ºF).
• The fuel control intrusive diagnostics are not active.
• The engine is operating under light acceleration, heavy acceleration, or cruise conditions.
• DTCs P2096 and P2097 run continuously when the conditions above have been met.

Conditions for Setting the DTC

The correction limit for a condition causing a lean or rich air/fuel ratio has been exceeded.

Action Taken when the DTC Sets

DTCs P2096 and P2097 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2096 and P2097 are Type B DTCs.

Diagnostic Aids

• The post catalyst fuel trim diagnostic is very sensitive to heated oxygen sensor (HO2S) design. A non-OE sensor or an incorrect part number may cause a DTC to set.
• Certain aftermarket air filters may cause a DTC to set.
• Certain aftermarket air induction systems or modifications to the air induction system may cause a DTC to set.
• Certain aftermarket exhaust system components may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0420 is not set.

• If the DTC is set

Refer to: DTC P0420

• Go to next step: If the DTC is not set

3. Verify no other HO2S or fuel trim DTC is set.

• If any other HO2S or fuel trim DTC is set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If no other HO2S or fuel trim DTC is set

4. Verify DTC P2096 or P2097 is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If no DTC is set

5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

6. Verify DTC P2096 or P2097 is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If no DTC is set

7. All OK.

Circuit/System Testing

Inspect for the conditions listed below:

P2096

• Air intake duct collapsed or restricted.
• Air filter dirty or restricted.
• Objects blocking the throttle body.
• Excessive fuel in the crankcase. Change engine oil as necessary.
• Rich fuel injectors. Refer to Fuel Injector Diagnosis.
• Excessive fuel system pressure. Refer to Fuel System Diagnosis.
• Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Fuel saturation of the evaporative emissions (EVAP) canister
• Stuck open or leaking EVAP purge valve
• Restricted exhaust. Refer to Symptoms - Engine Exhaust.
• Improperly operating crankcase ventilation system. Refer to Crankcase Ventilation System Inspection/Diagnosis.

P2097

• Exhaust system leaks. Refer to Symptoms - Engine Exhaust.
• Split, kinked, or improperly connected vacuum hoses
• Insufficient fuel in the tank
• Leaks in the air induction system and air intake ducts
• Missing air filter element
• Cracked evaporative canister
• Evaporative pipes plugged, obstructed, or leaking
• Crankcase ventilation system leaking. Refer to Crankcase Ventilation System Inspection/Diagnosis.
• Engine vacuum leaks
• Low fuel system pressure. Refer to Fuel System Diagnosis.
• Contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Lean fuel injectors. Refer to Fuel Injector Diagnosis.
• If a condition is found

Repair as necessary.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Perform the scan tool Fuel Trim Reset after completing the repair.

DTC P2122, P2123, P2127, P2128, or P2138

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptors

DTC P2122

Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2127

Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

Accelerator Pedal Position (APP) Sensors 1-2 Not Plausible

Diagnostic Fault Information

Typical Scan Tool Data

APP Sensor 1

APP Sensor 2

Circuit/System Description

The accelerator pedal assembly contains 2 accelerator pedal position (APP) sensors. The APP sensors are mounted to the accelerator pedal assembly and are not serviceable. The APP sensors provide a signal voltage that changes relative to pedal position. The engine control module (ECM) supplies each APP sensor with a 5 V reference circuit, a low reference circuit, and a signal circuit.

Conditions for Running the DTC

P2122, P2123, P2127, P2128

• DTC P0697 and P06A3 are not set.
• The ignition is ON or the engine is running.
• The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.
• DTC P2122, P2123, P2127, P2128 run continuously when the above conditions are met.

P2138

• DTC P0697, P06A3, P2122, P2123, P2127, and P2128 are not set.
• The ignition is ON or the engine is running.
• The run/crank or powertrain relay voltage is greater than 6.0 V and reduced power is not active.
• DTC P2138 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2122

The ECM detects the APP sensor 1 voltage is less than 0.46 V for greater than 1 s.

P2123

The ECM detects the APP sensor 1 voltage is greater than 4.75 V for greater than 1 s.

P2127

The ECM detects the APP sensor 2 voltage is less than 0.32 V for greater than 1 s.

P2128

The ECM detects the APP sensor 2 voltage is greater than 2.6 V for greater than 1 s.

P2138

The ECM detects the voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

• DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.
• The control module commands the TAC system to operate in the Reduced Engine Power mode.
• A message center or an indicator displays Reduced Engine Power.
• Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Ensure that the in-line harness connector seals are installed correctly. Improper installation could result in water intrusion into the connector and cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Throttle Actuator Control (TAC) System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC P0697 or P06A3 is not set.

• If any of the DTCs are set

Refer to DTC P0641, P0651, P0697, P06A3, or P06D2 for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Verify the scan tool APP Sensor 1 Circuit Status and APP Sensor 2 Circuit Status parameters display OK.

• If OK is not displayed

Refer to Circuit/System Testing.

• Go to next step: If OK is displayed

4. Verify the scan tool APP Sensor 1 and 2 parameter displays Agree while performing the tests listed below:

• Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure several times.
• Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.
• If Disagree

Refer to Circuit/System Testing

• Go to next step: If Agree

5. Verify that DTC P2122, P2123, 2127, P2128, or P2138 is not set.

• If any of the DTCs are set

Refer to Circuit/System Testing

• Go to next step: If none of the DTCs set

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B107 Accelerator Pedal Position Sensor. It may take up to 2 min for all vehicle systems to power down.

2. Test for less than 5 Ω between the appropriate low reference circuit terminal listed below and ground.

• APP sensor 1 low reference circuit terminal 4
• APP sensor 2 low reference circuit terminal 5
• If 5 Ω or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

3. Ignition ON.

4. Test for 4.8 - 5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.

• APP sensor 1 5 V reference circuit terminal 2
• APP sensor 2 5 V reference circuit terminal 1
• If less than 4.8 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

5. Verify the scan tool APP sensor 1 and APP sensor 2 voltage parameters are less than 0.3 V.

• If 0.3 V or greater

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit terminal listed below and ground.

• APP sensor 1 signal circuit terminal 3
• APP sensor 2 signal circuit terminal 6
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K20 Engine Control Module.
• Go to next step: If less than 0.3 V

6. Install a 3 A fused jumper wire between the appropriate signal circuit terminal listed below and the 5 V reference circuit terminal 1.

• APP sensor 1 signal circuit terminal 3
• APP sensor 2 signal circuit terminal 6

7. Verify the scan tool APP sensor 1 or APP sensor 2 voltage parameter is greater than 4.8 V.

• If 4.8 V or less

1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.8 V

8. Test or replace the B107 Accelerator Pedal Position Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Accelerator Pedal with Position Sensor Assembly Replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P2199

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2199

Intake Air Temperature (IAT) Sensor 1-2 Not Plausible

Diagnostic Fault Information

IAT Sensor 1

IAT Sensor 2 and Intake Air Humidity

Typical Scan Tool Data

IAT Sensor 1

IAT Sensor 2 and Intake Air Humidity

Circuit/System Description

The intake air temperature (IAT) sensor 1 is a variable resistor that measures the temperature of the air in the sensor bore. The engine control module (ECM) supplies 5 V to the IAT sensor 1 signal circuit and a ground for the IAT sensor 1 low reference circuit. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF).

The IAT sensor 2 produces a frequency signal, based on the inlet air temperature, which is equal to the humidity present within the sensor bore. The signal varies with inlet air temperature and is displayed by the scan tool as ºC (ºF) and Hertz (Hz) and the relative humidity is displayed in percent (%).

The ECM supplies a regulated voltage to the signal circuit. The signal circuit is shared by the IAT sensor 2 and the humidity sensor. Ignition voltage and ground circuits are also supplied to the multifunction intake air sensor's internal circuits for these sensors:

• IAT sensor 2
• Humidity sensor
• MAF sensor

The multifunction intake air sensor houses the following:

• IAT sensor 1
• IAT sensor 2
• Humidity sensor
• MAF sensor
• BARO pressure sensor

IAT Sensor 1 - Temperature, Resistance, Voltage Table

IAT Sensor 2 - Temperature, Frequency Table

Conditions for Running the DTC

• The ignition is ON.
• Ignition 1 voltage is at least 11 V.
• This DTC runs continuously within the enabling conditions.

Conditions for Setting the DTC

The ECM detects that the absolute difference between the IAT sensor 1 and the IAT sensor 2 temperatures is greater than 55ºC (99ºF) for longer than 5 s.

Action Taken When the DTC Sets

DTC P2199 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2199 is a Type B DTC.

Diagnostic Aids

• With the ignition ON, the engine OFF, if the engine is cold, a properly functioning IAT sensor 2 will gradually increase the scan tool IAT Sensor 2 parameter. This is due to the heat that is generated by the multifunction intake air sensor heating elements.
• The humidity sensor and the IAT sensor 2 signals are sent to the ECM on the same circuit. If the IAT Sensor 2 parameter displays the values: 10 Hz; -40ºC (-40ºF), and there are Humidity Sensor DTCs, check for a circuit problem.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Powertrain Component Views

Powertrain Component Views

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38522-A Variable Signal Generator

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

1. Ignition On.

2. Verify that DTC P0097, P0098, P0099, P00F4, P00F5, P00F6, P0102, P0103, P0112, P0113, P0114, P0641, P0651, P0697, P06A3 or P06D2 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If none of the DTCs are set

3. Ignition ON.

4. Verify the following scan tool parameters are within 30ºC (54ºF) of each other.

• Start-Up IAT Sensor 1
• IAT Sensor 2
• If not within 30ºC (54ºF)

Refer to Circuit/System Testing.

• Go to next step: If within 30ºC (54ºF)

5. Engine running, verify the following scan tool parameters are between: -38 and +149ºC (-36 and +300ºF).

• IAT Sensor 1
• IAT Sensor 2
• If not between: -38 and +149ºC (-36 and +300ºF)

Refer to Circuit/System Testing.

• Go to next step: If between: -38 and +149ºC (-36 and +300ºF)

6. Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

7. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

8. All OK

Circuit/System Testing

NOTE: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Check the integrity of the entire air induction system and verify that none of the following conditions exist:

• A restricted or collapsed air intake duct
• An intake manifold leak
• A misaligned or damaged air intake duct
• Any water intrusion in the induction system
• If a condition exists

Repair or replace component as appropriate.

• Go to next step: If no condition exists

2. Ignition Off, and all vehicle systems Off, it may take up to 2 min. for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air sensor.

3. Test for less than 5 Ω between the low reference circuit terminal 3 and ground.

• If 5 Ω or greater

1. Disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

Test for less than 5 Ω between the ground circuit terminal 7 and ground.

• If 5 Ω or greater

1. Ignition Off.
2. Test for less than 2 Ω in the ground circuit end to end.
   • If 2 Ω or greater, repair the open or high resistance in the circuit.
   • If less than 2 Ω, repair the open/high resistance in the ground connection.

• Go to next step: If less than 5 Ω

5. Ignition On.

6. Verify that a test lamp illuminates between the ignition circuit terminal 5 and ground.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition Off, remove the test lamp, the fuse for the ignition voltage circuit, and disconnect all components on the circuit.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition Off, remove the test lamp and remove the fuse for the ignition voltage circuit.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, test all components connected to the ignition circuit, replace as necessary.

• Go to next step: If a test lamp illuminates

7. Verify the scan tool Intake Air Temperature Sensor 1 parameter is colder than -39ºC (-38ºF).

• If warmer than -39ºC (-38ºF).

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 1 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If colder than -39ºC (-38ºF).

8. Ignition Off, install a 3 A fused jumper wire between the IAT 1 signal circuit terminal 1 and the low reference circuit terminal 3.

9. Ignition On.

10. Verify the scan tool Intake Air Temperature Sensor 1 parameter is warmer than 148ºC (298ºF).

• If colder than 148ºC (298ºF).

1. Ignition Off, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Ignition On.
3. Test for less than 1 V between the signal circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
4. Ignition Off.
5. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If warmer than 148ºC (298ºF).

11. Ignition On.

NOTE: The intake air temperature sensor 2 signal circuit is pulled up with low current voltage within the controller. Normally, a voltage near B+ can be measured on the circuit with a DMM, but the current will not be high enough to illuminate a test lamp.

12. Verify the scan tool Intake Air Humidity Sensor parameter is less than 1%.

• If 1% or greater

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the IAT 2 signal circuit terminal 8 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • If infinite resistance, replace the K20 Engine Control Module.

• Go to next step: If less than 1%

13. Ignition Off, install a 3 A fused jumper wire between the IAT 2 signal circuit terminal 8 and the low reference circuit terminal 3.

14. Ignition On.

15. Verify the scan tool Intake Air Humidity Sensor parameter is greater than 99%.

• If 99% or less

NOTE: If the signal circuit is shorted to a voltage the engine control module or the sensor may be damaged.

1. Ignition Off, remove the jumper wire and disconnect the harness connector at the K20 Engine Control Module.
2. Ignition On.
3. Test for less than 1 V between the IAT 2 signal circuit terminal 8 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V.
4. Ignition Off.
5. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 99%

16. Test or replace the B75C Multifunction Intake Air sensor.

Component Testing

Multifunction Intake Air Sensor

1. Ignition Off, disconnect the harness connector at the B75C Multifunction Intake Air Sensor.

2. Connect a DMM between the IAT sensor 1 signal terminal 1 and the low reference terminal 3

NOTE: A thermometer can be used to test the sensor off the vehicle.

3. Test the IAT sensor 1 by varying the sensor temperature while monitoring the sensor resistance.

Compare the readings with the Temperature Versus Resistance - Intake Air Temperature Sensor table for Hitachi Sensors. The resistance values should be in range of the table values.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

4. All OK.

Multifunction Intake Air Sensor

1. Test the IAT Sensor 2 by varying the sensor temperature while monitoring the air temperature with a thermometer. Compare the readings with the scan tool IAT Sensor 2 parameter. The values should be within 5%.

• If not within the specified range

Replace the B75C Multifunction Intake Air Sensor.

• Go to next step: If within the specified range

2. All OK.

Testing with EL-38522-A

NOTE: In-correct diagnosis will result if Circuit/System Testing is not completed before performing the following test.

1. Perform the following test using a EL-38522-A Variable Signal Generator or equivalent, if available.

2. Ignition Off, connect the leads of the EL-38522-A Variable Signal Generator as follows:

1. Red lead to the signal circuit terminal 8 at the harness connector
2. Black leads to ground
3. Battery voltage supply lead to B+

3. Set the EL-38522-A Variable Signal Generator to the following specifications.

• Signal switch to 5 V
• Duty Cycle switch to 50 % (Normal)
• Frequency switch to 250 Hz

4. Ignition On.

5. Verify the scan tool IAT Sensor 2 parameters listed below are within the ranges listed below:

• IAT Sensor 2 is between 248 - 252 Hz

NOTE: Changing the frequency should cause a warmer or colder IAT 2 temperature.

• IAT Sensor 2 is between 70 - 76ºC (160 - 166ºF)

NOTE: Increasing or decreasing the duty cycle should have an inverse affect on humidity.

• Intake Air Humidity Sensor is between 48 - 52%
• If a parameter is not within the specified range

Replace the K20 Engine Control Module.

• Go to next step: If all the parameters are within the specified range

6. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup.

DTC P219A

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P219A

Fuel Trim Cylinder Balance

Circuit/System Description

The Fuel Trim Cylinder Balance diagnostic detects a rich or lean cylinder to cylinder air/fuel ratio imbalance. The diagnostic monitors the pre-catalyst heated oxygen sensor (HO2S) signal's frequency and amplitude characteristics by calculating an accumulated voltage over a predetermined sample period. An imbalance is indicated when multiple samples of the accumulated voltage are consistently higher than the desired value.

Conditions for Running the DTC

• DTCs P0016, P0017, P0030, P0036, P0053, P0054, P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0116, P0117, P0118, P0019, P0122, P0123, P0128, P0131 - P0135, P0137, P0138, P013A, P013B, P013E, P013F, P0140, P0141, P0171, P0172, P0201 - P0204, P0222, P0223, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301 - P0304, P0340, P0341, P0365, P0366, P0411, P0442, P0455, P0458, P0496, P111E, P1133, P1248, P1249, P124A, P124B, P16A0, P16A1, P16A2, P16F3, P2101, P2135, P2147, P2148, P2150. P2151, P2153, P2154, P2156, P2157, P2270, P2271, P2440, P2444 or P2A00 are not set.
• The evaporative emission system device control and intrusive diagnostics are not active.
• The engine overspeed protection is not active.
• The engine is in closed loop status.
• The system voltage is greater than 11 V.
• The engine coolant temperature (ECT) is warmer than -20ºC (-4ºF).
• The engine speed is between 1, 200 - 4, 000 RPM.
• The mass air flow is between 0 - 100 g/s.
• The secondary air injection pump (if equipped) is not ON.
• The Exhaust Camshaft Position and Intake Camshaft Position are between 0 - 35 degrees.

  Engine run time is greater than 30 s.

• Fuel level is greater than 10% and no fuel level sensor fault is present.
• The DTC runs continuously when the above conditions have been met.

Conditions for Setting the DTC

Multiple samples of the pre-catalyst HO2S accumulated voltage are consistently greater than the desired value.

Action Taken When the DTC Sets

DTC P219A is a Type A DTC.

Conditions for Clearing the MIL/DTC

DTC P219A is a Type A DTC.

Diagnostic Aids

• The fuel trim cylinder balance diagnostic is very sensitive to heated oxygen sensor (HO2S) design. A non-OE sensor or an incorrect part number may cause a DTC to set.
• Monitoring the misfire current counters, or misfire graph, may help to isolate the cylinder that is causing the condition.
• Certain aftermarket air filters may cause a DTC to set.
• Certain aftermarket air induction systems or modifications to the air induction system may cause a DTC to set.
• Certain aftermarket exhaust system components may cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Component View Reference

Powertrain Component Views

Electrical Information Reference

• Circuit Testing
• Troubleshooting with a Test Lamp
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Connector Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify no other DTCs are set.

• If any other DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• Go to next step: If no other DTCs are set

3. Verify DTC P219A is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If no DTC is set

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

5. Verify DTC P219A is not set.

• If a DTC is set

Refer to Circuit/System Testing.

• Go to next step: If no DTC is set

6. All OK.

Circuit/System Testing

1. Engine idling, transmission in Park or Neutral, verify the manifold absolute pressure (MAP) sensor parameter is between 20 - 48 kPa.

• If not within the specified range.

Refer to DTC P0106.

• Go to next step: If within the specified range, inspect for the conditions listed below:
• Modified, damaged, leaking, or restricted air induction system components.
• Improperly operating crankcase ventilation system. Refer to Crankcase Ventilation System Inspection/Diagnosis.
• Split, kinked, or improperly connected vacuum hoses.
• Restricted, damaged, leaking, or modified exhaust system from the catalytic converter forward. Refer to Symptoms - Engine Exhaust.
• Improperly operating fuel injectors. Refer to Fuel Injector Diagnosis.
• Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Excessive fuel in the crankcase due to leaking injectors. Change engine oil as necessary.
• Improperly operating ignition system. Refer to Electronic Ignition System Diagnosis.
• If a condition is found

Repair as necessary.

• Go to next step: If no condition is found

2. Test the engine for any mechanical conditions such as sticking valves, lifters, etc., which could alter the flow into the combustion chamber. Refer to Symptoms - Engine Mechanical.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Perform the scan tool Fuel Trim Reset after completing the repair.

DTC P2227-P2230

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P2227

Barometric Pressure (BARO) Sensor Performance

DTC P2228

Barometric Pressure (BARO) Sensor Circuit Low Voltage

DTC P2229

Barometric Pressure (BARO) Sensor Circuit High Voltage

DTC P2230

Barometric Pressure (BARO) Sensor Circuit Erratic

Diagnostic Fault Information

Typical Scan Tool Data

BARO

Circuit/System Description

The barometric pressure (BARO) sensor is integral to the multifunction intake air sensor and responds to changes in altitude and atmospheric conditions. This gives the ECM an indication of barometric pressure. The ECM uses this information to calculate fuel delivery. The BARO sensor provides a voltage signal to the ECM relative to the atmospheric pressure changes. The ECM monitors the BARO sensor signal for a voltage outside of the normal range.

Conditions for Running the DTC

P2227

• Engine is running.
  • DTC P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0117, P0118, P0119, P0121, P0122, P0123, P0222, P0223, P1516, P2101, P2135, P2228, or P2229 is not active.
  • DTC P2227 runs continuously when the above conditions are met.

    OR

• Ignition is On, engine is Off for at least 10 s.
  • DTC P0106, P0107, P0108, P2228, P2229, P2230, or P2610 is not active.
  • DTC P0107, P0108, P2228, or P2229 is not pending.
  • DTC P2227 runs continuously when the above conditions are met.

P2228 or P2229

• Engine is running.
• The DTCs run continuously when the above condition is met.

P2230

• DTC P0068, P0101, P0102, P0103, P0106, P0107, P0108, P0111, P0112, P0113, P0114, P0117, P0118, P0119, P0121, P0122, P0123, P0222, P0223, P1516, P2101, P2135, P2228, or P2229 is not set.
• Ignition is On
• DTC P2230 runs continuously when the above conditions are met.

Conditions for Setting the DTC

P2227

• The engine is running.
  • The ECM detects that the difference between the actual BARO and the calculated BARO is greater than 15 kPa when the distance traveled since the last calculated BARO update is less than or equal to 0.1 km (0.06 mi).

    OR

  • The ECM detects that the difference between the actual BARO and the calculated BARO is greater than 20 kPa when the distance traveled since the last calculated BARO update is greater than 0.1 km (0.06 mi).

    OR

• Ignition On, engine Off
  • The ECM detects that the BARO pressure is less than 50 kPa (7.3 psi) or greater than 115 kPa (16.7 psi).

    OR

  • The ECM detects that the absolute value of the difference between MAP and actual BARO is greater than 10 kPa and the absolute value of the difference between Boost Pressure and MAP is less than or equal to 10 kPa and the absolute value of the difference between Boost Pressure and BARO is greater than 10 kPa.

P2228

The ECM detects that the BARO sensor voltage is less than 1.7 V for greater than 5 s.

P2229

The ECM detects that the BARO sensor voltage is greater than 4.5 V for greater than 5 s.

P2230

The ECM detects that the cumulative difference between BARO sensor readings, over a specific length of time, is greater than a calibrated threshold.

Action Taken When the DTC Sets

DTCs P2227, P2228, P2229, and P2230 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2227, P2228, P2229, and P2230 are Type B DTCs.

Diagnostic Aids

A skewed boost pressure sensor (Turbocharger Boost/Intake Air Temperature Sensor) may cause this DTC to set.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition On.

2. Verify the scan tool BARO parameter is within the range specified in the Altitude Versus Barometric Pressure table.

• If the BARO is not within the specified range

Refer to Circuit/System Testing.

• Go to next step: If the BARO is within the specified range

3. Verify the scan tool Boost Pressure parameter and the BARO parameter are within 3 kPa (0.43 PSI).

• If not within 3 kPa (0.43 PSI)

Refer to DTC P0236.

• Go to next step: If within 3 kPa (0.43 PSI)

4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed in the Freeze Frame/Failure Records data.

5. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

6. All OK.

Circuit/System Testing

1. Verify the conditions listed below do not exist with the B75C Multifunction Intake Air Sensor:

• Damage
• Restrictions in the inlet port
• If a condition exists

Repair or replace the B75C Multifunction Intake Air Sensor as necessary.

• Go to next step: If none of the conditions exist

2. Ignition Off, and all vehicle systems Off, it may take up to 2 min for all vehicle systems to power down. Disconnect the harness connector at the B75C Multifunction Intake Air Sensor.

3. Test for less than 5 Ω between the low reference circuit terminal 3 and ground.

• If 5 Ω or greater

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 Ω in the low reference circuit end to end.
   • If greater than the specified value, repair the open or high resistance in the circuit.
   • If 2 Ω or less replace the K20 Engine Control Module.

• Go to next step: If less than 5 Ω

4. Ignition On.

5. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 2 and ground.

• If less than 4.8 V

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the 5 V reference circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the 5 V reference circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• If greater than 5.2 V

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the 5 V reference circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If between 4.8 - 5.2 V

6. Verify the scan tool BARO Sensor parameter is less than 0.2 V.

• If 0.2 V or greater

1. Ignition Off, disconnect the harness connector at the K20 Engine Control Module, ignition On.
2. Test for less than 1 V between the signal circuit terminal 4 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, replace the K20 Engine Control Module.

• Go to next step: If less than 0.2 V

7. Install a 3 A fused jumper wire between the signal circuit terminal 4 and the 5 V reference circuit terminal 2.

8. Verify the scan tool BARO Sensor parameter is greater than 4.5 V.

• If 4.5 V or less

1. Ignition Off, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal 4 and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.
   • Go to next step: If infinite resistance
3. Test for less than 2 Ω in the signal circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the K20 Engine Control Module.

• Go to next step: If greater than 4.5 V

9. Test or replace the B75C Multifunction Intake Air Sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Mass Airflow Sensor with Intake Air Temperature Sensor Replacement for multifunction intake air sensor replacement
• Control Module References for engine control module replacement, programming, and setup

DTC P2261

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2261

Turbocharger Bypass Valve Stuck

Circuit/System Description

The dual-scroll turbocharger incorporates a wastegate that is controlled by the engine control module (ECM) by means of a pulse width modulation (PWM) solenoid, to regulate the pressure ratio of the compressor. An ECM controlled compressor bypass valve is integrated into the unit to prevent compressor surging and damage from vibrations by opening during abrupt closed throttle conditions.

The bypass valve is open during closed throttle deceleration conditions to allow air to recirculate in the turbocharger and maintain compressor speed.

Conditions for Running the DTC

• DTC P0033, P0034, P0035, P0101, P0102, P0103, P0236, P0237, or P0238 is not set.

  Engine speed is at least 1, 500 rpm

• The boost pressure versus the BARO pressure ratio is between 1.1 - 3.3.
• The turbocharger bypass valve has been commanded Open greater than 6% for greater than 1 s immediately after an abrupt closed throttle has occurred and the resulting pressure ratio across the compressor exceeds the calibrated pressure ratio limit.
• The DTC runs continuously when the above conditions have been met.

Conditions for Setting the DTC

The ECM has detected a series of pulsations in the induction system that exceed a calibrated threshold.

Action Taken When the DTC Sets

DTC P2261 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2261 is a Type B DTC.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Description and Operation

Turbocharger System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information.

Circuit/System Verification

1. Ignition On.

2. Verify that DTC P0033, P0034, or P0035 is not set

• If any of the DTCs are set

Refer to DTC P0033-P0035.

• Go to next step: If none of the DTCs are set

3. Verify the scan tool BARO Sensor parameter is within the range specified in the Altitude Versus Barometric Pressure table for the current testing altitude.

• If the parameter is not within the range specified in the table.

Refer to DTC P2227-P2230.

• Go to next step: If the parameter is within the range specified in the table.

4. Verify the scan tool Boost Pressure Sensor and BARO Sensor parameters are within 3 kPa (0.4 psi).

• If the parameters are not within 3 kPa (0.4 psi).

Refer to DTC P0236.

• Go to next step: If the parameters are within 3 kPa (0.4 psi).

5. Verify a click is heard or felt from the Q40 Turbocharger Bypass Solenoid Valve when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• If a click is not heard or felt

Refer to Circuit/System Testing

• Go to next step: If a click is heard or felt

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

7. Verify a DTC does not set.

• If a DTC sets

Refer to Circuit/System Testing

• Go to next step: If a DTC does not set

8. All OK

Circuit/System Testing

NOTE: Leave harness connector connected or re-connect it after removing valve.

1. Ignition Off, remove the Q40 Turbocharger Bypass Solenoid Valve from the turbocharger, ignition On.

2. Verify the turbocharger bypass valve plunger retracts and extends when commanding the Turbocharger Bypass Solenoid Valve between Active and Inactive with a scan tool.

• The valve plunger does not retract and extend

Replace the Q40 Turbocharger Bypass Solenoid Valve

• Go to next step: The valve plunger retracts and extends

3. Verify the conditions listed below do not exist with the turbocharger assembly. Refer to Camshaft Cover and Compressor Air Intake Turbocharger Cleaning and Inspection

• Cracked, damaged or worn turbine blades
• Restricted wastegate, turbine, ports or passages
• Foreign material
• If a condition exists

Repair or replace the turbocharger as necessary

• Go to next step: If none of the conditions exist

4. Replace the Q40 Turbocharger Bypass Solenoid Valve

Component Testing

Static Test

1. Ignition Off, disconnect the harness connector at the Q40 Turbocharger Bypass Solenoid Valve.

2. Test for 10 - 14 Ω between the control terminal 2 and the Ignition terminal 1 of the Q40 Turbocharger Bypass Solenoid Valve.

• If not between 10 - 14 Ω

Replace the Q40 Turbocharger Bypass Solenoid Valve.

• Go to next step: If between 10 - 14 Ω

3. All OK

Dynamic Test

1. Install a 10 A fused jumper wire between the ignition terminal 2 of the Q40 Turbocharger Bypass Solenoid Valve and 12 V. Install a jumper wire between the control terminal 1 and ground.

2. Verify the Q40 Turbocharger Bypass Solenoid Valve plunger retracts.

• If the plunger does not retract.

Replace the Q40 Turbocharger Bypass Solenoid Valve.

• Go to next step: If the plunger retracts.

3. All OK

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Turbocharger Bypass Valve Solenoid Replacement

DTC P2618 OR P2619

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

DTC Descriptor

DTC P2618

Crankshaft Position Signal Output Circuit Low Voltage

DTC P2619

Crankshaft Position Signal Output Circuit High Voltage

Conditions for Running the DTC

• Ignition Voltage=Greater than 11 V
• Ignition=On
• Crankshaft Position Sensor Circuit=Active

Frequency the DTC runs=Continuously - After the running conditions are met

Conditions for Setting the DTC

P2618

Crankshaft Position Signal Output Circuit=Short to Groundor Open - For greater than 5 s

P2619

Crankshaft Position Signal Output Circuit=Short to Voltage - For greater than 5 s

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type C DTC

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type C DTC

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Circuit/System Verification

1. Engine - Running.

2. Verify there are no DTCs/symptoms related to the following system/component, if equipped:

• K71 Transmission Control Module
• K103 Fuel Injector Control Module
• T3 Audio Amplifier
• T6 Power Inverter Module
• If a DTC or symptom exists

Refer to:

• Diagnostic Trouble Code (DTC) List - Vehicle
• Symptoms - Vehicle
• Go to next step: If no DTC or symptom exists

3. All OK.

DTC P2635 or P2BB3

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC P2635

Fuel Pump Flow Performance

DTC P2BB3

Fuel Pump Feedback Performance

Circuit/System Description

The engine control module (ECM) supplies voltage to the fuel pump power control module when the ECM detects that the ignition is on. The voltage from the ECM to the fuel pump power control module remains active for 2 s, unless the engine is in crank or run. While this voltage is being received, the fuel pump power control module closes the ground switch of the fuel pump. The fuel pump power control module maintains correct fuel pressure based on the information from the fuel pressure sensor and varying the Pulse Width Modulation (PWM) controlled current to the fuel pump.

Conditions for Running the DTC's

DTC P2635

• DTC P018B, P018C, P018D, P0231, P0232, P023F, P0641 or P1255 are not active.

  Fuel pump control is enabled, the fuel pump control state and pressure control state are normal.

• The ignition voltage is between 11 - 32 V.
• The engine has been running for greater than 30 s.
• The engine fuel flow is not 0.
• Low fuel level warning not present.
• The DTC runs continuously when the conditions above are met.

DTC P2BB3

• The ignition voltage is greater than 11 V
• The fuel pump duty cycle command measured and received is in error for greater than 0.1 s
• The DTC runs continuously when the conditions above are met.

Conditions for Setting the DTC's

The fuel pump power control module detects a difference of ÂÂ+- 60 kPa at 400 kPa request or ÂÂ+-45 kPa at 300 kPa request between the desired fuel pressure and the actual fuel pressure for approximately 10 s.

Action Taken When the DTC Sets

DTC P2635 is a Type B DTC.

DTC P2BB3 is a Type A DTC.

Conditions for Clearing the DTC

DTC P2635 is a Type B DTC.

DTC P2BB3 is a Type A DTC.

Diagnostic Aids

Using the Failure Records data may help locate an intermittent condition. If you cannot duplicate the DTC, the information in the Failure Records can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can help determine how many ignition cycles that the diagnostic test reported a pass and/or a fail.

On vehicles equipped with a high pressure mechanical pump on Direct Fuel Injection engines, the vehicle may continue to run even though the pump in the fuel tank is not operating.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Verify DTC U0074 or U18A2 is not set or stored in history.

• If DTC U0074 or U18A2 is set or stored in history

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If DTC U0074 or U18A2 is not set or stored in history

3. Verify that DTC P018B, P018C, P018D, P0231, P0232, or P023F is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

4. Verify the scan tool Short Term Fuel Pump Trim and the Long Term Fuel Pump Trim when multiplied together are less than 1.5.

• If greater than 1.5

Refer to Circuit/System Testing.

• Go to next step: If less than 1.5

5. Command the Fuel Pressure to 300 kPa (43.5 PSI) using the scan tool Control Function: Fuel Pressure Increase/Decrease.

6. Verify the scan tool parameter: Fuel Pressure Sensor & Desired Fuel Pressure are within 45 kPa (6.5 PSI) of each other at 300 kPa (43.5 PSI) request.

• If greater than 45 kPa (6.5 PSI)

Refer to Circuit/System Testing.

• Go to next step: If less than 45 kPa (6.5 PSI)

7. Command the Fuel Pressure to 400 kPa (58 PSI) using the scan tool Control Function: Fuel Pressure Increase/Decrease.

8. Verify the scan tool parameter: Fuel Pressure Sensor & Desired Fuel Pressure are within 60 kPa (8.7 PSI) of each other at 400 kPa (58 PSI) request.

• If greater than 60 kPa (8.7 PSI)

Refer to Circuit/System Testing.

• Go to next step: If less than 60 kPa (8.7 PSI)

9. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset.

You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

10. Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing.

• Go to next step: If the DTC does not set

11. All OK.

Circuit/System Testing

NOTE: Do not replace the fuel pump power control module based on a history DTC P2635. DTC P2635 may be stored but that does not indicate a failure of the fuel pump power control module. Refer to Strategy Based Diagnosis for further history DTC diagnostics.

1. Verify the proper fuel system pressure. Refer to Fuel System Diagnosis.

• If the fuel pressure is not normal

Repair the fuel system as necessary.

• Go to next step: If the fuel pressure is normal

2. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Fuel Feed Front Pipe Replacement
• Fuel Feed Pipe Replacement - Underbody
• Fuel Injector Replacement
• Fuel Tank Fuel Pump Module Replacement (FWD) or Fuel Tank Fuel Pump Module Replacement (AWD)
• Perform the Fuel Pump Trim Reset procedure with a scan tool after the repair.

Repair Verification

1. Install any components that have been removed or replaced during diagnosis.

2. Perform any adjustments, programming or setup procedures that are required when a component is removed or replaced.

3. Clear the DTCs with a scan tool.

4. Turn OFF the ignition for 60 s.

5. Operate the vehicle within the Conditions for Running the DTC.

6. Verify the scan tool Short Term Fuel Pump Trim and the Long Term Fuel Pump Trim when multiplied together are less than 1.5.

• If greater than 1.5

Refer to Circuit/System Testing.

• Go to next step: If less than 1.5

7. Command the Fuel Pressure to 300 kPa (43.5 PSI) using the scan tool Control Function: Fuel Pressure Increase/Decrease.

8. Verify the scan tool parameter: Fuel Pressure Sensor & Desired Fuel Pressure are within 45 kPa (6.5 PSI) of each other at 300 kPa (43.5 PSI) request.

• If greater than 45 kPa (6.5 PSI)

Refer to Circuit/System Testing.

• Go to next step: If less than 45 kPa (6.5 PSI)

9. Command the Fuel Pressure to 400 kPa (58 PSI) using the scan tool Control Function: Fuel Pressure Increase/Decrease.

10. Verify the scan tool parameter: Fuel Pressure Sensor & Desired Fuel Pressure are within 60 kPa (8.7 PSI) of each other at 400 kPa (58 PSI) request.

• If greater than 60 kPa (8.7 PSI)

Refer to Circuit/System Testing.

• Go to next step: If less than 60 kPa (8.7 PSI)

11. All OK.

Symptoms - Engine Controls

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provide an overview of each diagnostic category.

Symptoms Description

Symptoms covers conditions that are not covered by DTCs. Certain conditions can cause multiple symptoms. These conditions are listed together under Symptoms Testing. Conditions that may only cause specific symptoms are listed separately under Additional Symptoms Tests. Perform the Symptoms Testing before using the Additional Symptoms Tests.

Symptoms Definition

Backfire

The Fuel ignites in the intake manifold or in the exhaust system, making a loud popping noise.

Cuts Out, Misses

A steady pulsation or jerking that follows engine speed, which is usually more pronounced as the engine load increases. This condition is not normally felt above 1, 500 RPM or 48 km/h (30 mph).

The exhaust has a steady spitting sound at idle or at low speed.

Detonation/Spark Knock

A mild to severe ping which usually occurs worse while under acceleration. The engine makes sharp metallic knocks that change with throttle opening.

Dieseling, Run-On

The engine continues to run after the key is turned OFF, but runs very rough.

Engine Control Module (ECM) Commanded Reduced Engine Power

The ECM illuminates the Reduced Engine Power lamp and will limit engine power under potential engine/vehicle damaging or emissions related conditions. A DTC may not be set.

Fuel Odor A noticeable smell of unburned fuel.

Hard Start

The engine cranks OK, but does not start for a long time. The vehicle does eventually run, or may start but immediately stall.

Hesitation, Sag, Stumble

A momentary lack of response as the accelerator is pushed down. This condition can occur at any vehicle speed. This condition is usually more pronounced when first trying to make the vehicle move, as from a stop. This condition may cause the engine to stall in severe conditions.

Lack of Power, Sluggishness, or Sponginess

The engine delivers less than expected power. Little or no increase in vehicle speed when the accelerator pedal is pushed down part way.

Poor Fuel Economy

Fuel economy, as measured by an actual road test, is noticeably lower than expected. Also, the fuel economy is noticeably lower than it was on this vehicle at one time, as previously shown by an actual road test.

Rough, Unstable, or Incorrect Idle and Stalling

The engine runs unevenly at idle. If severe, the engine or the vehicle may shake. Engine idle speed may vary. Either condition may be severe enough to stall the engine.

Surges/Chuggles

An engine power variation under steady throttle or cruise. Feels like the vehicle speeds up and slows down with no change in the accelerator pedal position.

Symptoms Verification

Before using the Symptom tables, perform the following inspections:

• Verify the malfunction indicator lamp (MIL) is operating correctly. Use the scan tool to command the lamp ON and OFF.
• Verify there are no DTCs that are stored.
• Verify the scan tool data is within a normal operating range. Refer to Control Module References for scan tool information.
• Verify the customer concern.
• Perform the "Visual/Physical Check" described below. The visual/physical inspection is extremely important, and can lead to correcting a condition without additional testing. It may also help reveal the cause of an intermittent condition.

Identifying Intermittent Conditions

Many intermittent conditions occur with harness or connector movement due to engine torque, rough pavement, vibration or physical movements of a component. Refer to the following for a list of issues that may cause an intermittent condition:

• Moisture and water intrusion in connectors, terminals, and components Incomplete connector mating
• Poor terminal contact
• High circuit or component resistance - High resistance can include any resistance, regardless of the amount, which can interrupt the operation of the component.
• Harness that is too short or tight
• Wire insulation that is chaffed or cut
• High or low ambient temperature
• High or low engine coolant temperatures
• High underhood temperatures
• Heat build up in component or circuit due to circuit resistance, poor terminal contact, or high electrical load
• High or low system voltage
• High vehicle load conditions
• Rough road surfaces
• Electro-magnetic interference (EMI)/circuit interference from relays, solenoids or other electrical surge
• Incorrect installation of aftermarket, add on accessories

Visual/Physical Check

• Verify the control module grounds are clean, tight, and correctly located.
• Verify the vacuum hoses are not split or kinked, and are properly connected.
• Verify the air filter is clean and free from restrictions.
• Verify there is no water intrusion in connectors terminals and components.
• Inspect the air intake ducts for the conditions listed below:
  • Collapsed
  • Damaged areas
  • Looseness
  • Incorrect installation
  • Leaking

    If any condition listed above has allowed non-metered air to enter the air induction system, the Throttle Body Idle Air Flow Compensation Reset procedure must be performed after the repair is complete.

• Inspect for air leaks at the throttle body mounting area, the mass air flow (MAF) sensor and intake manifold sealing surfaces.
• Inspect the wiring harness for the following conditions:
  • Poor connections
  • Pinches
  • Cuts
• Inspect for loose, damaged, unseated, or missing sensors/components.
• Inspect the terminals for corrosion and correct contact.

Symptoms Testing

Backfire, Cuts Out/Misses, Detonation/Spark Knock, Dieseling/Run-On, Engine Control Module (ECM) Commanded Reduced Engine Power, Fuel Odor, Hard Start, Hesitation/Sag/Stumble, Lack of Power/Sluggishness/Sponginess, Poor Fuel Economy, Rough, Unstable, or Incorrect Idle and Stalling, or Surges/Chuggles

• Test/inspect the fuel system for the conditions listed below:
  • Incorrect system operation or fuel pressure - Refer to Fuel System Diagnosis.
  • leaking or incorrectly operating fuel injectors - Refer to Fuel Injector Diagnosis and Fuel Injector Circuit Diagnosis.
  • Contaminated or poor quality fuel - Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• Test/inspect the ignition system for the conditions listed below:
  • Spark plugs with incorrect heat range or an abnormal condition - Refer to Spark Plug Inspection and Ignition System Specifications.
  • Coolant or oil fouled spark plugs - For diagnosis, refer to Coolant in Combustion Chamber or Oil Consumption Diagnosis.
  • Secondary ignition system susceptible to moisture. Engine running, wet down the secondary ignition system with water from a spray bottle to help locate damaged or deteriorated components. Look/listen for arcing or misfiring as the water is applied.
  • Weak spark using the J-26792 Spark Tester - Refer to Electronic Ignition System Diagnosis.
• Test/inspect for the conditions listed below:
  • Non-metered air flow into the air induction system. If a leak is found, repair as necessary.

    The Throttle Body Idle Air Flow Compensation Reset procedure must be performed when the repair is complete.

  • Incorrectly operating transmission torque converter clutch (TCC) - The scan tool should indicate an engine speed drop when the TCC is commanded ON. For M3D or M3T, refer to Torque Converter Diagnosis (LTG) or Torque Converter Diagnosis (LGX). For MRC, refer to Torque Converter Diagnosis.
  • Incorrectly operating A/C compressor.
  • An engine that runs lean or rich. Observe the Fuel Trim parameters with a scan tool - Refer to DTC P0171 or P0172 for more information.
  • Slow responding heated oxygen sensors (HO2S) - The HO2S should respond quickly to different throttle positions - Refer to DTC P0137, P0138, P013A, P013B, P013E, P013F, P2270, or P2271 for more information.

CAUTION: Refer to Heated Oxygen and Oxygen Sensor Caution.

• Water intrusion in the HO2S connector

NOTE: The embossed arrows on the mass air flow (MAF) sensor indicate the direction of the intake air flow. The arrows must point toward the engine.

• Incorrect mass air flow sensor installation. A mass air flow sensor that is incorrectly installed may cause a hard start. Install the mass air flow in the correct direction. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Incorrect mass air flow sensor connections.
• A MAF sensor contaminated by an excessively oiled aftermarket air filter. Some aftermarket air filters require oil to be added to the air filter element. If the MAF sensor becomes contaminated as the result of an excessively oiled aftermarket air filter, a variety of driveability concerns and/or erratic transmission shifting may occur.
• Engine oil contaminated by fuel
• Split or kinked vacuum hoses - Verify that the routing and connections are correct.
• Excessive knock sensor system spark retard activity - Observe the Knock Retard parameter on the scan tool for activity more than 0º.
• Electromagnetic interference (EMI) on the reference circuit, which can cause a misfire condition. You can usually detect electromagnetic interference with a scan tool by monitoring the engine speed parameter. A sudden increase in the engine speed parameter with little change in actual engine speed indicates that electromagnetic interference is present. Inspect the high voltage components near the ignition control circuit if a condition exists.
• A crankshaft position sensor with an intermittent condition - Observe the scan tool Crankshaft Position Resync Counter parameter. The Resync Counter parameter should remain at 0 during all operating conditions, and when moving the related harnesses and connectors between the crankshaft position sensor and the ECM.
• A stuck open evaporative emission (EVAP) canister purge solenoid.
• Incorrectly operating crankcase ventilation valve - Refer to Crankcase Ventilation System Inspection/Diagnosis.

• Test/inspect the engine cooling system for the conditions listed below:
  • A thermostat with incorrect heat range. Refer to Thermostat Diagnosis.
  • Incorrect engine coolant level - If the level is low, refer to Loss of Coolant.

    For additional information, refer to Symptoms - Engine Cooling.

• Test/inspect the exhaust system components for the conditions listed below:
  • Physical damage or possible internal failure.
  • Restricted three-way catalytic converters.

    For additional information, refer to Symptoms - Engine Exhaust.

• Test/inspect the engine for the mechanical conditions listed below:
  • Excessive oil in the combustion chamber or leaking valve seals
  • Oil consumption
  • Incorrect cylinder compression
  • Sticking or leaking valves
  • Worn camshaft lobes
  • Incorrect valve timing
  • Worn rocker arms
  • Broken valve springs
  • Excessive carbon buildup in the combustion chambers - Clean the chambers with Top Engine Cleaner, if necessary. Follow the instructions on the can.

    Incorrect engine parts

  • For additional information, refer to Symptoms - Engine Mechanical.
• If the above conditions do not address the symptom, refer to the Additional Symptoms Tests.

Additional Symptoms Tests

Detonation/Spark Knock

• Verify that the engine coolant temperature (ECT) has not shifted in value. Allow the engine to run and reach operating temperature. Observe the ECT Sensor parameter with a scan tool and compare the reading to that parameter listed on the K20 Engine Control Module: Scan Tool Information , list. If the reading is not in the range specified in the list, test the resistance of the ECT sensor. Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor , for resistance specifications. Replace the ECT sensor if the resistance is not within specification.

  Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the ECT sensor circuits for high resistance.

• Test for an engine overheating condition. Refer to Engine Overheating.
• Inspect for excessive carbon buildup in the combustion chambers. Clean the chambers with Top Engine Cleaner, if necessary. Follow the instructions on the can.
• If there are no engine mechanical faults, fill the fuel tank with a known high quality fuel that meets the vehicle minimum octane requirements.

ECM Commanded Reduced Engine Power

Under certain conditions the engine control module may limit engine power by reducing engine torque and, for some vehicles, fuel pressure as well. For most, but not all of the conditions, the engine control module will illuminate the reduced engine power lamp on the instrument panel cluster, however a DTC may not be set.

A repair may not be necessary. Observe the scan tool Reduced Engine Power History parameter, if applicable, or refer to K20 Engine Control Module: Scan Tool Information to determine the reason for the reduced engine power event.

Verify or inspect for the following:

• Vehicle being operated at sustained high engine speeds, or, towing heavy loads up an incline for an extended period of time, which may cause the engine oil or coolant to overheat. Inspect the airflow passageways in front of the engine for obstructions and clear away any debris or foreign material that is found. If no obstructions are found, review approved driving habits with the customer. The customer may need to operate the vehicle at a higher engine speed to improve cooling system performance, or, at a slower engine speed to reduce engine load.
• A cooling fan condition which may cause the engine control module to reduce engine power.

  Refer to Description and Operation to verify correct operation of the cooling fan.

• Temporarily reduced engine power. Under extremely cold ambient temperatures some SIDI equipped vehicles may experience ECM commanded reduced engine power for a few minutes during engine warm-up. This would be a normal condition, noticeable only at wide open throttle, and the reduced engine power lamp would not be illuminated.
• Reduced engine power due to OnStar remote command. Verify the vehicle is not in the OnStar initiated Stolen Vehicle Slowdown mode.
• Turbocharger boost pressure out of range, if equipped. Refer to DTC P0234 or P0299.
• High pressure fuel system condition. Refer to Fuel System Diagnosis and Fuel System Description to verify high pressure fuel system operation.
• Intake air temperature out of range too high. Observe the scan tool IAT Sensor 1 and IAT Sensor 2 parameters. The readings should be within 9ºC (16ºF) of a each other.
• Fuel temperature out of range too high. Observe the scan tool Fuel Temperature Sensor parameter.
• If equipped with automatic transmission, an incorrect learned brake pedal position (BPP) sensor.

  Verify the following actions have not occurred:

  • An engine control module has been replaced
  • A BPP sensor that has been replaced
  • An incorrect BPP sensor alignment or installation

    If any of the above actions occurred, the Brake Pedal Position Sensor Calibration must be performed:

Fuel Odor

• Inspect for leaking, damaged, or deteriorated fuel lines.
• Inspect for a saturated EVAP canister - Refer to Evaporative Emission Control System Description.
• Inspect for a condition with the internal components of the fuel tank assembly - Refer to Fuel System Description.

Hard Start

• Observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. A value greater than 90 % may indicate an excessive accumulation of deposits in the throttle bore. Inspect the throttle body and clean, if necessary. Refer to Throttle Body Cleaning.
• Test the engine coolant temperature (ECT) sensor. Compare the ECT sensor value to the intake air temperature (IAT) sensor value on a cold engine. The ECT and IAT sensor values should be within ÂÂ+- 3ºC (5ºF). If the engine coolant temperature sensor is out of range with the intake air temperature sensor, test the resistance of the engine coolant temperature sensor. Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor , for resistance specifications. Replace the engine coolant temperature sensor if the resistance is not within specification. Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the engine coolant temperature sensor circuits for high resistance.
• Verify that the fuel system has adequate pressure for engine start-up. The fuel pump should turn ON for 2 s when the ignition is turned ON. Refer to Fuel System Description and Fuel System Diagnosis.
• Inspect for excessive crankshaft endplay that will cause the crankshaft position sensor reluctor wheel to move out of alignment with the crankshaft position sensor. Refer to Crankshaft and Bearing Cleaning and Inspection and Engine Mechanical Specifications.

Hesitation, Sag, Stumble

• Test the fuel pressure. Refer to Fuel System Diagnosis.
• Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Test the generator. Refer to Symptoms - Engine Electrical. Repair the charging system if the generator output voltage is less than 9 V or more than 16 V.
• Test the manifold absolute pressure (MAP) sensor. Refer to DTC P0106.
• Inspect for excessive crankshaft endplay that will cause the crankshaft position sensor reluctor wheel to move out of alignment with the crankshaft position sensor. Refer to Crankshaft and Bearing Cleaning and Inspection and Engine Mechanical Specifications.

NOTE: The following actions may need to be repeated in order to verify an intermittent intake or exhaust camshaft actuator condition.

• Engine warm and idling, verify the correct operation of the camshaft actuator system. Command the intake and exhaust camshaft actuators from 0 degrees to 20 degrees and back to zero while observing the scan tool Intake Camshaft Position Variance and Exhaust Camshaft Position Variance parameters. Each parameter should be less than 2 degrees in each of the commanded states.
  • If any of the parameters is greater than 2 degrees, inspect the suspect camshaft actuator and camshaft actuator solenoid valve and valve bore for contamination, obstruction, and damage. Refer to Camshaft Position Actuator Exhaust Solenoid Valve Replacement , Camshaft Position Actuator Intake Solenoid Valve Replacement , and Camshaft Actuator System Description.

Lack of Power, Sluggishness, or Sponginess

• Inspect the engine electrical system for incorrect operation. Refer to Symptoms - Engine Electrical.
• Verify that each injector harness is connected to the correct injector.
• Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Verify the correct operation of the turbocharger system. Perform the following:
  • Inspect the turbocharger moving components for looseness, binding, wear and damage.
  • Verify that the turbocharger air inlet ducts and outlet ducts are tightly sealed and that the air passages are not obstructed. Engine running, use a solution of dish soap and water in a spray bottle to pinpoint any air leaks.
  • Inspect the turbocharger system for external fluid leaks. Inspect the gaskets and sealing surfaces and look for cracks in the turbocharger components. Refer to Turbocharger Leaking Fluids Externally and Turbocharger Smoke or Smell.
  • Inspect for excessive turbocharger system noise. Refer to Turbocharger Noise.
  • Inspect for a loss of turbocharger pressure. Refer to Turbocharger Loss of Boost Pressure.
  • For additional information, refer to Turbocharger System Description and Camshaft Cover and Compressor Air Intake Turbocharger Cleaning and Inspection.

NOTE: The following actions may need to be repeated in order to verify an intermittent intake or exhaust camshaft actuator condition.

• Engine warm and idling, verify the correct operation of the camshaft actuator system. Command the intake and exhaust camshaft actuators from 0 degrees to 20 degrees and back to zero while observing the scan tool Intake Camshaft Position Variance and Exhaust Camshaft Position Variance parameters. Each parameter should be less than 2 degrees in each of the commanded states.
  • If any of the parameters is greater than 2 degrees, inspect the suspect camshaft actuator and camshaft actuator solenoid valve and valve bore for contamination, obstruction, and damage. Refer to Camshaft Position Actuator Exhaust Solenoid Valve Replacement , Camshaft Position Actuator Intake Solenoid Valve Replacement , and Camshaft Actuator System Description.

Poor Fuel Economy

• Observe the Throttle Body Idle Airflow Compensation parameter with a scan tool. A value greater than 90 % may indicate an excessive accumulation of deposits in the throttle bore. Inspect the throttle body and clean, if necessary. Refer to Throttle Body Cleaning.
• Inspect for heavy loads being carried or towed
• Inspect for acceleration rate too much or too often
• Inspect for incorrect operation of the speedometer.
• Verify that the engine coolant temperature (ECT) has not shifted in value. Allow the engine to run and reach operating temperature. Observe the ECT Sensor parameter with a scan tool and compare the reading to that parameter listed on the K20 Engine Control Module: Scan Tool Information , list. If the reading is not in the range specified in the list, test the resistance of the engine coolant temperature sensor. Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor , for resistance specifications. Replace the engine coolant temperature sensor if the resistance is not within specification. Refer to Engine Coolant Temperature Sensor Replacement. If the sensor is within the specification, test the engine coolant temperature sensor circuits for high resistance.
• Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Inspect the brake system for brake drag.

Rough, Unstable, or Incorrect Idle and Stalling

• An excessively high idle may be due to the floor mat interfering with the accelerator pedal. With this condition present, it may not be possible to shift the transmission into gear. Inspect the accelerator pedal for binding and verify that the floor mat is not interfering with the accelerator pedal movement.
• Engine idle speed may be unstable or the engine may stall if the ECM has learned an incorrect idle/airflow compensation value. A DTC may also set. Observe the scan tool Throttle Body Idle Airflow Compensation parameter. A value greater than 90% may indicate an excessive accumulation of deposits in the throttle bore. If the throttle body needs cleaning, refer to Throttle Body Cleaning.

The actions listed below may also cause the ECM to learn an incorrect idle value.

• The engine control module has been replaced
• The throttle body has been replaced
• The throttle body has been cleaned but the idle learn procedure was not performed after completing the cleaning
• The air induction system was leaking, allowing non-metered air to enter the combustion chamber. The leak was repaired but the idle learn procedure was not performed after repairing the leak

If any of the actions listed above have occurred, the Throttle Body Idle Air Flow Compensation Reset procedure must be performed.

• Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Inspect the engine mounts. Refer to Engine Mount Inspection.
• Inspect the intake and exhaust manifolds for casting flash.

Surges/Chuggles

• Verify that each injector harness is connected to the correct injector.
• Inspect the mass air flow (MAF) sensor for obstruction, contamination, and damage. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement.
• Inspect for slow responding heated oxygen sensors (HO2S). The HO2S should respond quickly to a change in throttle position. If the HO2S do not respond to different throttle positions, inspect for contamination from fuel, silicon, or the incorrect use of RTV sealant. The sensors may have a white powdery coating and result in a high, but false, signal voltage, which gives a rich exhaust indication. The PCM reduces the amount of fuel delivered to the engine, causing a driveability condition. Refer to DTC P0137, P0138, P013A, P013B, P013E, P013F, P2270, or P2271 for more information.

Malfunction Indicator Lamp (MIL) Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Aids

If the condition is intermittent, move the related harnesses and connectors while monitoring the scan tool MIL control circuit status parameters. Perform this test with the ignition ON and the engine OFF, and with the engine running. The MIL control circuit status parameters change from OK or Not Run to Malfunction if there is a condition with a circuit or a connection.

Reference Information

Schematic Reference

• Engine Controls Wiring Schematics (LTG)
• Instrument Cluster Wiring Schematics

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: Any MIL requesting DTCs that may be set should be diagnosed first.

1. Ignition ON.

2. Verify the parameters listed below do not display Malfunction when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• The MIL Control Circuit Low Voltage Test Status
• The MIL Control Circuit Open Test Status
• The MIL Control Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

3. Engine running.

4. Verify the parameters listed below do not display Malfunction when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• The MIL Control Circuit Low Voltage Test Status
• The MIL Control Circuit Open Test Status
• The MIL Control Circuit High Voltage Test Status
• If Malfunction is displayed

Refer to Circuit/System Testing.

• Go to next step: If Malfunction is not displayed

5. Verify the malfunction indicator lamp turns ON and OFF when commanding the Malfunction Indicator Lamp On and Off with a scan tool.

• If the malfunction indicator lamp does not turn ON and OFF

Refer to Circuit/System Testing.

• Go to next step: If the malfunction indicator lamp turns ON and OFF

6. All OK.

Circuit/System Testing

1. Ignition OFF.

2. Disconnect the X1 harness connector at the K20 Engine Control Module.

3. Ignition ON, verify the malfunction indicator lamp does not illuminate.

• If the malfunction indicator lamp illuminates

1. Test for infinite resistance between the control circuit terminal X1 71 and ground.
   • If less than infinite resistance, repair the short to ground in the circuit.
   • If infinite resistance, replace the P16 Instrument Cluster.

• Go to next step: If the malfunction indicator lamp does not illuminate

4. Connect a 3 A fused jumper wire between the control circuit terminal X1 71 and ground.

5. Verify the malfunction indicator lamp illuminates.

• If the malfunction indicator lamp illuminates

Replace the K20 Engine Control Module.

• If the malfunction indicator lamp does not illuminate

1. Test for less than 1 V between the control circuit terminal X1 71 and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • Go to next step: If less than 1 V
2. Ignition OFF.
3. Test for less than 2 Ω in the control circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω.

6. Ignition OFF, disconnect the X1 harness connector at the instrument cluster.

7. Ignition ON, verify a test lamp illuminates between the ignition voltage circuit terminal 8 and ground.

• If the test lamp does not illuminate and the circuit fuse is open

1. Ignition OFF.
2. Test for infinite resistance between the ignition voltage circuit and ground.
   • If less than infinite resistance, repair the short to ground on the circuit.

• If the test lamp does not illuminate and the circuit fuse is good

1. Ignition OFF.
2. Test for less than 2 Ω in the ignition voltage circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.

• Go to next step: If the test lamp illuminates

8. Replace the P16 Instrument Cluster.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• Instrument Cluster Replacement
• Control Module References for control module replacement. programming, and setup

Engine Cranks But Does Not Run

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

This Engine Cranks but Does Not Run is an organized approach to identify a condition which causes the engine to crank but not start. This diagnostic directs the technician to the appropriate system diagnosis.

Diagnostic Aids

Inspect for any of the conditions listed below:

• If equipped with a key type ignition system, a partially retracted or folded over ignition key. When attempting to start the engine, the mechanical portion of the vehicle key must be locked in the fully extended position with the fob parallel to the key. Leaving the key partially retracted or folded over when starting may interrupt transponder authentication and result in an intermittent no-start condition. In such instances, DTC B3055 may also be set. If an intermittent no-start complaint is received, it may be necessary to discuss with the customer their starting habits and verify they are locking the key in the fully extended position, fob parallel to the key, before starting.
• A crankshaft position sensor condition. When this condition is present, the engine control module (ECM) uses the camshaft position sensors to determine engine speed and position. If the condition exists in the signal circuit of the sensor, the engine will go into a limp home mode after a hard restart. The ECM then calculates engine speed from one of the camshaft position sensors.

  However, the engine will operate with a crankshaft position sensor condition only if the ECM has stored the learned reference position of the camshafts in memory.

• An in-tank fuel pump condition. The fuel pump control module controls and monitors the operation of the in-tank fuel pump. If the fuel pump control module detects a fault, a DTC sets in the fuel pump control module. The fuel pump control module will then send a serial data message to the engine control module (ECM) requesting the illumination of the malfunction indicator lamp (MIL).
• Insufficient fuel. Thoroughly inspect the fuel delivery system for sufficient fuel volume to the fuel injectors. Inspect the fuel supply components for partial blockage or restrictions.
• Fuel injectors with partially blocked and restricted nozzles, or a malfunctioning solenoid. Refer to Fuel Injector Diagnosis and Fuel Injector Circuit Diagnosis for diagnosis.
• Fuel injector ON time inadequate. When this condition is present, there may be fuel spray at the fuel injectors and the indicated fuel pressure may be correct, yet there may not be enough fuel to start the engine. If the engine control module (ECM) receives incorrect inputs from the various information sensors, the fuel delivered by the fuel injectors may be inadequate to start the engine.

  Check all the engine data parameters with a scan tool and compare the values indicated with the expected values or the values from a known good vehicle.

• Loose unsecured engine electrical grounds. Inspect the engine for good secure electrical grounds.
• Water or foreign material in the fuel, which can cause either a no start or a engine will not stay running condition. During freezing weather water can freeze inside the fuel system. The engine may start after 30 min in a heated repair shop. The malfunction may not recur until parked overnight in freezing temperatures. Extreme weather conditions can cause contaminated fuel to prevent the vehicle from starting.
• An ignition system that is susceptible to moisture. An engine that starts and runs after being brought into a warm, dry repair shop, may be susceptible to moisture. Spray water on the ignition system components and wiring while cranking the engine in order to check for an engine starting or will not stay running concern.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Starting System Description and Operation

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 26792 HEI Spark Tester

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

NOTE:

This diagnostic assumes the following:

• The battery is completely charged.
• The engine cranking speed is acceptable.
• There is adequate fuel in the fuel tank.

1. Crank the engine for up to 15 s.

2. Verify that P0201 - P0204, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P1248, P1249, P124A, P124B, P2147, P2148, P2150, P2151, P2153, P2154, P2156, P2157, P0335, P0336, P0351 - P0354, P0601, P0602, P0603, P0604, P0606, P0607, P060E, P062F, P0685, P0689, P0690, P069E, P1516, P1682, P2610, or P2635 is not set.

• If any of the DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If none of the DTCs are set

3. Ignition ON.

4. Verify the security indicator on the instrument panel cluster illuminates momentarily.

• If the indicator stays ON or is flashing

Refer to Diagnostic Trouble Code (DTC) List - Vehicle and Immobilizer Description and Operation.

• Go to next step: If the indicator does not stay ON and is not flashing

5. Verify the scan tool Engine Speed parameter is greater than 0 RPM while cranking the engine.

• If 0 RPM

Refer to DTC P0335 or P0336 for further diagnosis.

• Go to next step: If greater than 0 RPM

6. Ignition OFF.

7. Disconnect a T8 ignition coil from a cylinder and spark plug.

8. Connect a J 26792 HEI Spark Tester between the boot of the ignition coil and ground.

NOTE: An erratic or weak spark is considered a no spark condition.

9. Verify that the spark tester sparks while cranking the engine.

• If the spark tester does not spark

Refer to Electronic Ignition System Diagnosis for further diagnosis.

• Go to next step: If the spark tester sparks

10. Ignition ON.

NOTE:

• If the engine is too hot, high fuel pressure readings may result due to hot soak fuel boiling. Allow the engine coolant temperature to cool to less than 60º C (150º F) before attempting to verify fuel pressure.
• The Fuel Pump Enable may need to be commanded On a few times in order to obtain the highest possible fuel pressure.
• Additional DTCs may set when using the fuel pump output control.

11. Command the Fuel Pump Enable On several times with a scan tool.

12. Verify that the scan tool Fuel Pressure Sensor parameter is between 345 - 650 kPa (50 - 94 psi) while the fuel pump is running.

• If not within the specified range

Refer to Fuel System Diagnosis.

• Go to next step: If within the specified range

13. Verify that the scan tool Fuel Pressure Sensor parameter, after the pump has turned OFF, decreases to less than 600 kPa (87 psi), and does not decrease greater than 34 kPa (5 psi) in 1 minute.

• If not within the specified range

Refer to Fuel System Diagnosis.

• Go to next step: If within the specified range

14. Verify that the conditions listed below do not exist:

• Collapsed or restricted air intake duct to the throttle body
• Restricted air filter
• Gas or coolant fouled spark plugs
• A skewed manifold absolute pressure (MAP) sensor. Refer to DTC P0106
• A skewed engine coolant temperature (ECT) sensor. Refer to DTC P0117, P0118, or P0119
• A restricted exhaust system. Refer to Restricted Exhaust.
• Contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis.
• An engine mechanical condition, for example, worn timing chain and gears or low compression. Refer to Symptoms - Engine Mechanical or Engine Compression Test
  • If a condition exists

    Repair as necessary.

  • Go to next step: If no conditions exist

15. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Fuel System Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The engine control module (ECM) supplies voltage to the fuel pump power control module when the ECM detects that the ignition is ON. The voltage from the ECM to the fuel pump power control module remains active for 2 s, unless the engine is in Crank or Run. While this voltage is being received, the fuel pump power control module closes the ground switch of the fuel tank fuel pump module and also supplies a varying voltage to the fuel tank fuel pump module in order to maintain the desired fuel line pressure.

The fuel system is an electronic returnless on-demand design. A returnless fuel system reduces the internal temperature of the fuel tank by not returning hot fuel from the engine to the fuel tank. Reducing the internal temperature of the fuel tank results in lower evaporative emissions.

An electric turbine style fuel pump attaches to the fuel tank pump module inside the fuel tank. The fuel pump supplies fuel through the fuel feed pipe to the high pressure fuel pump. The high pressure fuel pump supplies fuel to a variable-pressure fuel rail. Fuel enters the combustion chamber through precision multi-hole fuel injectors. The high pressure fuel pump, fuel rail pressure, fuel injection timing, and injection duration are controlled by the engine control module (ECM).

Diagnostic Aids

Observe the Misfire Counters or perform the Fuel Injector Balance Test to help identify a leaking fuel injector.

Reference Information

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EN 37287 Fuel Line Shut-Off Adapter

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

Circuit/System Verification

NOTE:

• Repair all fuel system related DTCs, except P2635, before performing this diagnostic.
• Inspect the fuel system for damage or external leaks before proceeding.
• Verify that adequate fuel is in the fuel tank before proceeding.
• The Fuel Pump Enable may need to be commanded ON a few times in order to obtain the highest possible fuel pressure.
• DO NOT perform the Fuel System Diagnosis if the engine coolant temperature is above 60ºC (150ºF). High fuel pressure readings may result due to hot soak fuel boiling. With the engine OFF, the fuel pressure may increase beyond the pressure relief regulator valve's setting point of 690 kPa (100 psi) ÂÂ+- 5 percent.

1. Ignition ON, engine OFF, command the Fuel Pump Enable On several times with a scan tool.

2. Verify the Fuel Pressure Sensor parameter is between 345 - 650 kPa (50 - 94 psi) with the fuel pump running.

• If less than 345 kPa (50 psi)

Refer to Fuel Pressure Low in Circuit/System Testing.

• If greater than 650 kPa (94 psi)

Replace the G12 Fuel Pump.

• Go to next step: If between 345 - 650 kPa (50 - 94 psi)

3. Verify that the Fuel Pressure Sensor parameter, after the fuel pump is turned off, decreases to less than 600 kPa (87 psi).

• If greater than 600 kPa (87 psi)

Replace the G12 Fuel Pump.

• Go to next step: If less than 600 kPa (87 psi)

4. Verify that the Fuel Pressure Sensor parameter does not decrease greater than 34 kPa (5 psi) in 1 minute.

• If greater than 34 kPa (5 psi)

Refer to Fuel Pressure Leaks Down in Circuit/System Testing.

• Go to next step: If less than 34 kPa (5 psi)

5. Engine idling.

6. Verify the Fuel Pressure Sensor parameter is between 300 - 400 kPa (43 - 58 psi).

• If less than 300 kPa (43 psi)

Refer to Fuel Pressure Low in Circuit/System Testing.

• If greater than 400 kPa (58 psi)

Replace the G12 Fuel Pump.

• Go to next step: If between 300 - 400 kPa (43 - 58 psi)

7. Verify the scan tool Short Term Fuel Pump Trim and the Long Term Fuel Pump Trim when multiplied together are less than 1.5.

• If greater than 1.5

Refer to Fuel Pressure Low in Circuit/System Testing.

• Go to next step: If less than 1.5

8. Verify the scan tool Pressure Sensor and the Desired Fuel Pressure are within 45 kPa (6.5 psi) at 300 kPa (43.5 psi) request or 60 kPa (8.7 psi) at 400 kPa (58 psi) request of each other while operating the vehicle through varying loads.

• If greater than 45 kPa (6.5 psi)/60 kPa (8.7 psi)

Refer to Fuel Pressure Drops Off in Circuit/System Testing.

• Go to next step: If less than 45 kPa (6.5 psi)/60 kPa (8.7 psi)

9. If the fuel system components test normal, refer to Symptoms - Engine Controls and Fuel Injector Diagnosis for further diagnosis.

Circuit/System Testing

Fuel Pressure Low

1. Verify none of the conditions listed below exist:

• Restricted fuel feed pipe
• Inspect the harness connectors and the ground circuits of the fuel pump for poor connections.
• If a condition exists

Repair as necessary.

• Go to next step: If no conditions exist

Go to next step: Replace the G12 Fuel Pump.

Fuel Pressure Leaks Down

1. Ignition OFF, relieve the fuel pressure. Refer to Fuel Pressure Relief.

2. Install the EN 37287 Adapter between the chassis fuel feed hose and the high pressure fuel pump.

3. Open the valve on the EN 37287 Adapter.

4. Ignition ON, command the Fuel Pump Enable On and then Off with a scan tool.

5. Close the valve on the EN 37287 Adapter.

6. Verify that the Fuel Pressure Sensor parameter does not decrease greater than 34 kPa (5 psi) in 1 minute.

• If greater than 34 kPa (5 psi)

Replace the G12 Fuel Pump.

• Go to next step: If less than 34 kPa (5 psi)

Fuel Pressure Drops Off

1. Verify none of the conditions listed below exist:

• Restricted fuel feed pipe
• Inspect the harness connectors and the ground circuits of the fuel pump for poor connections.
• If a condition exists

Repair as necessary.

• Go to next step: If no conditions exist

Go to next step: Replace the G12 Fuel Pump.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel Feed Front Pipe Replacement
• Fuel Injector Replacement
• Fuel Tank Fuel Pump Module Replacement (FWD) or Fuel Tank Fuel Pump Module
• Replacement (AWD)

Fuel Leak Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

Diagnostic Aids

Fluorescent dye assists in locating leaks in the system. A high-intensity black light will make the dye glow. - Green or Yellow Illuminate the area(s) of concern For example:

• G18 High Pressure Fuel Pump
• Q17 Fuel Injector
• Fuel Line
• Fuel Rail
• { If equipped } Fuel Return Pipe

Reference Information

Special Tools

• J-28428-E High-Intensity Black Light Kit
• J-42220 Universal 12 V Leak Detection Lamp

Circuit/System Verification

1. Perform the following action: Clean all of the components in the suspected area using a cleaning solution and allow the components to dry: Fuel System

2. Perform the following action: Add 237 mL (8 US fl oz) of GM Approved Oil Dye to the component: Fuel Tank - Primary

3. Engine - Idling - For 3 to 5 min

4. Perform the scan tool control function: Fuel Pressure Control - Regulator 1 - Increase - Maximum Pressure - If applicable

CAUTION: When performing a Fuel Leak Diagnosis, it is VERY IMPORTANT to use only GM approved Oil Dye, Part Number 88861206. If any other oil dye is used, it will cause damage to the fuel injection system components, as well as the emission control components. This will result in necessary replacement of the damaged components.

5. Use the special tool: J-28428-E High-Intensity Black Light Kit or J-42220 Universal 12 V Leak Detection Lamp - Illuminate the area(s) of concern

Verify there are no leaks in the component/system: High Pressure Side of the Fuel System or Return Side of the Fuel System

• { High Pressure Side of the Fuel System } If a leak is present

Repair or replace as necessary.

• { Return Side of the Fuel System } If a leak is present

Refer to: Diagnostic Procedure Instructions

• Go to next step: If no leak is present

6. All OK.

Fuel Injector Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

Two methods of testing fuel injector balance are available, the Active Fuel Injector Tester or a scan tool.

The Active Fuel Injector Tester and SIDI adaptor connects to the engine control module harness connectors to test the high pressure fuel pump performance, fuel injector wiring, and fuel injector operation. The Active Fuel Injector Tester displays step by step instructions to precisely determine pressure drop of each fuel injector. The scan tool fuel injector balance test is performed while the engine is running at idle. The scan tool pressurizes the fuel rail to a predetermined pressure before each fuel injector is pulsed for a precise amount of time allowing a measured amount of the fuel to be injected.

This causes a drop in the system fuel pressure that is recorded and used to compare each fuel injector.

Diagnostic Aids

• Monitoring the scan tool Cylinder 1-4 Current Misfire Counters may help to isolate the fuel injector that is causing the condition.
• Operating the vehicle over a wide temperature range may help isolate the fuel injector that is causing the condition.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Special Tools

• CH-47976 Active Fuel Injector Tester
• CH-47976-500 Active Fuel Injection Tester SIDI Adapter Kit
• CH-47976 - 503 Active Fuel Injection Tester cable G3
• CH-47976 - 512 Active Fuel Injection Tester cable G3b Adapter

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools)

Fuel Injector Coil Test

NOTE:

• The resistance test must be performed at the fuel injector or misdiagnosis will occur.
• The DMM and test leads must be calibrated to 0 Ω in order to prevent mis-diagnosis.

1. Disconnect the appropriate Q17 Fuel Injector.

2. Test for 1.3 - 1.44 Ω at 20ºC (68ºF) between the control + circuit terminal 2 and the control - circuit terminal 1 at the Q17 Fuel Injector.

• If not between 1.3 - 1.44 Ω

Replace the Q17 Fuel Injector.

• Go to next step: If between 1.3 - 1.44 Ω

3. Test for infinite resistance between each terminal at the Q17 Fuel Injector and the Q17 Fuel Injector housing/case.

• If less than infinite resistance

Replace the Q17 Fuel Injector.

• Go to next step: If infinite resistance

4. All OK. Perform the Fuel Injector Balance Test.

Fuel Injector Balance Test

NOTE:

• DO NOT perform this test if the engine coolant temperature (ECT) is above 60ºC (140ºF). Irregular fuel pressure readings may result due to hot soak fuel boiling.
• Verify that adequate fuel is in the fuel tank before proceeding with this diagnostic.

Fuel Injector Balance Test with Active Fuel Injector Tester - Preferred Method

1. Verify the battery is fully charged and all accessories are OFF.

2. Ignition OFF, all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down. Install CH-47976 and CH-47976-500. Connect CH-47976 - 503 and CH-47976 - 512 to CH-47976-500.

NOTE:

• Important that voltage is jumped to the correct fuse terminal.
• Not all (KL9) vehicle are affected. Only vehicles listed below require this jumper step.

3. For applications with Start/Stop (KL9), battery voltage must be jumped to the low/negative side of the fuse for the KR27 Starter Relay using a 3 amp fused jumper wire. Reference below to determine the appropriate fuse to remove for your application.

• Cruze (LE2) - Fuse F16UA, Fuse 16, "Fuel Injection"
• Envision (LCV / LTG) - Fuse F3UA, Fuse F03, "NON/WALK"
• Equinox/Terrain (LYX / LTG) - Fuse F3UA, Fuse 3, "Lambda 1"
• Malibu (LFV / LKN / LTG) - Fuse F76UA, Fuse 76, "PWR/TRN OFF Engine"
• Insignia (LGX / LTG) - Fuse F46UA, Fuse 46, "ECM IGN"

4. Turn ON the Active Fuel Injector Tester and select the vehicle.

5. Ignition ON, perform the Injector Test with the Active Fuel Injector Tester.

• If the Active Fuel Injector Tester aborts testing due to incorrect fuel pressure or fuel leak down

Refer to Fuel System Diagnosis.

• Go to next step: If the Active Fuel Injector Tester does not abort testing

6. Compare the test results with the appropriate recommended tolerance.

• If any fuel injector exceeds the recommended tolerance

Replace the appropriate Q17 Fuel Injector(s).

• Go to next step: If all fuel injectors are within the recommended tolerance

7. All OK.

Fuel Injector Balance Test with Scan Tool

1. Verify the correct low side fuel pressure. Refer to Fuel System Diagnosis.

2. Engine idling, verify the scan tool Fuel Rail Pressure Sensor parameter is approximately 3 MPa (435 PSI).

NOTE: The engine speed must be between 600 - 1000 RPM to perform this test.

3. Select the Fuel Injector Balance function within the Control Functions menu of a scan tool.

4. Select and test an injector. Repeat for each injector.

5. Obtain and record a pressure drop value for each injector.

6. Add all of the individual pressure drop values except for the injector suspected of being faulty.

This is the total pressure drop.

NOTE: For engines with 2 banks of cylinders, only measure average pressure drop on cylinders that are on the same bank.

7.

8. Divide the total pressure drop by the number of fuel injectors that were added together. This is the average pressure drop.

9. Multiply the average pressure drop by 0.20. This is the acceptable variance from the average pressure drop, 20 percent.

10. Verify the difference between any individual pressure drop and the average pressure drop is not greater than the acceptable variance.

• If greater than the acceptable variance

Replace the Q17 Fuel Injector.

• Go to next step: If within the acceptable variance

11. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

Fuel Injector Circuit Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit/System Description

The engine control module (ECM) supplies voltage to each fuel injector on the injector high voltage supply circuits. The ECM energizes each fuel injector by grounding the high voltage control circuit of the fuel injector. The ECM monitors the status of the injector high voltage supply circuits and the injector high voltage control circuits. When a fuel injector circuit condition is detected by the ECM, the affected fuel injector(s) is disabled.

Diagnostic Aids

• Performing the fuel injector coil test may help isolate an intermittent condition. Refer to Fuel Injector Diagnosis.
• If the condition is intermittent, move the related harnesses and connectors, with the engine operating, while monitoring the scan tool Injector Control Circuit Status parameters. An Injector Control Circuit Status parameter will change from OK or Not Run to Malfunction if there is a condition with the circuit or a connection.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index

Powertrain Component View

Powertrain Component Views

Description and Operation

Fuel System Description

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

NOTE: Do Not perform this procedure unless directed here from the Fuel Injector Balance Test.

1. Engine idling.

2. Verify the scan tool Cylinder 1 - 4 Current Misfire Counter parameters do not increment.

• If the Cylinder 1 - 4 Current Misfire Counters increment

Refer to Circuit/System Testing.

• Go to next step: If the Cylinder 1 - 4 Current Misfire Counters do not increment

3. Verify the scan tool Cylinder 1 - 4 Injector Control Circuit Status parameters display OK.

• If the Cylinder 1 - 4 Injector Control Circuit Status parameters do not display OK

Refer to Circuit/System Testing.

• Go to next step: If the Cylinder 1 - 4 Injector Control Circuit Status parameters display OK

4. All OK.

Circuit/System Testing

1. Ignition OFF, all vehicle systems OFF, disconnect the harness connector at the K20 Engine Control Module. It may take up to 2 min for all vehicle systems to power down.

2. Test for infinite resistance between the appropriate Q17 Fuel Injector control + circuit and ground.

• If less than infinite resistance

1. Disconnect the harness connector of the Q17 Fuel Injector.
2. Test for infinite resistance between the Q17 Fuel Injector control + circuit and ground.
   • If less than infinite, repair the short to ground in the circuit.
   • Go to next step: If infinite resistance
3. Test for infinite resistance between the Q17 Fuel Injector control - circuit and ground.
   • If less than infinite, repair the short to ground in the circuit.
   • If infinite, replace the Q17 Fuel Injector.

• Go to next step: If infinite resistance

3. Ignition ON.

4. Test for less than 1 V between the Q17 Fuel Injector control + circuit and ground.

• If 1 V or greater

1. Disconnect the harness connector of the Q17 Fuel Injector, ignition ON.
2. Test for less than 1 V between the Q17 Fuel Injector control + circuit and ground.
   • If 1 V or greater, repair the short to voltage on the circuit.
   • If less than 1 V, repair the short to voltage on the control - circuit.

• Go to next step: If less than 1 V

5. Ignition OFF.

6. Test for less than 3 Ω between the Q17 Fuel Injector control + circuit and control - circuit.

• If 3 Ω or greater

1. Disconnect the harness connector of the Q17 Fuel Injector.
2. Test for less than 2 Ω on the control + circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • Go to next step: If less than 2 Ω
3. Test for less than 2 Ω on the control - circuit end to end.
   • If 2 Ω or greater, repair the open/high resistance in the circuit.
   • If less than 2 Ω, replace the Q17 Fuel Injector.

• Go to next step: If less than 3 Ω

7. Replace the K20 Engine Control Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic repair.

• Control Module References for ECM replacement, programming and setup,
• Fuel Injector Replacement

Alcohol/Contaminants-In-Fuel Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Test Description

Water contamination in the fuel system may cause driveability conditions such as hesitation, stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector at the lowest point in the fuel injection system and cause a misfire in that cylinder. If the fuel system is contaminated with water, inspect the fuel system components for rust or deterioration.

Ethanol concentrations of greater than 10 percent can cause driveability conditions and fuel system deterioration. Fuel with more than 10 percent ethanol could result in driveability conditions such as hesitation, lack of power, stalling, or no start. Excessive concentrations of ethanol used in vehicles not designed for it may cause fuel system corrosion, deterioration of rubber components, and fuel filter restriction.

Reference Information

Special Tool

CH 44175-A Fuel Composition Tester, if available

For equivalent regional tools, refer to Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools).

System Verification

The fuel sample should be drawn from the bottom of the tank so that any water present in the tank will be detected. The sample should be bright and clear.

• If the sample appears cloudy, or contaminated with water, as indicated by a water layer at the bottom of the sample, perform the Particulate Contaminants in Fuel Testing Procedure.
• If alcohol contamination is suspected, perform the Alcohol in Fuel Testing procedure.

Alcohol in Fuel Testing with Special Tool, If Available

1. Test the fuel composition using the CH 44175-A Fuel Composition Tester. Refer to the User's Manual as necessary.

2. If water appears in the fuel sample, clean the fuel system.

3. Subtract 50 from the reading on the DMM in order to obtain the percentage of alcohol in the fuel sample.

4. If the fuel sample contains more than 15 percent ethanol, add fresh, regular gasoline to the vehicle's fuel tank.

5. Test the fuel composition.

6. If testing shows the ethanol percentage is still more than 15 percent, replace the fuel in the vehicle.

Alcohol in Fuel Testing without Special Tool

1. Using a 100 ml (3.38 oz) specified cylinder with 1 ml (0.034 oz) graduation marks, fill the cylinder with fuel to the 90 ml (3.04 oz) mark.

2. Add 10 ml (0.34 oz) of water in order to bring the total fluid volume to 100 ml (3.38 oz) and install a stopper.

3. Shake the cylinder vigorously for 10 - 15 seconds.

4. Carefully loosen the stopper in order to release the pressure.

5. Re-install the stopper and shake the cylinder vigorously again for 10 - 15 seconds.

6. Put the cylinder on a level surface for approximately 5 min in order to allow adequate liquid separation. If alcohol is present in the fuel, the volume of the lower layer, which would now contain both alcohol and water, will be more than 10 ml (0.34 oz). For example, if the volume of the lower layer is increased to 15 ml (0.51 oz), this indicates at least 5 percent alcohol in the fuel.

The actual amount of alcohol may be somewhat more because this procedure does not extract all of the alcohol from the fuel.

Particulate Contaminants in Fuel Testing Procedure

1. Using an approved fuel container, draw approximately 0.5 liter (0.53 qt) of fuel.

2. Place the container on a level surface for approximately 5 min in order to allow settling of the particulate contamination. Particulate contamination will show up in various shapes and colors.

Sand will typically be identified by a white or light brown crystals. Rubber will appear as black and irregular particles.

3. Observe the fuel sample. If any physical contaminants or water are present, clean the fuel system.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• Fuel System Cleaning
• Fuel Tank Draining

Evaporative Emission System Diagnosis

Special Tools

• CH-44284-2 Fuel Flapper Door Holder
• EN-41413-VLV EVAP Service Port Vent Fitting
• GE-41415-60 Engine Induction System Leak Test Adapter/Capless Fuel Fill Adapter

Operating Instructions for the Evaporative Emission System Tester

Vehicle Setup

WARNING: Refer to Fuel and Evaporative Emission Pipe Warning.

CAUTION: Use the Evaporative Emission (EVAP) System Tester GE 41413-A in order to provide a clean, dry, low pressure nitrogen gas source. Do not substitute any other pressurized source, gas or otherwise.

Damage may result to the EVAP system, test equipment or cause a safety risk.

NOTE: When servicing the evaporative emission (EVAP) system, test pressure must not exceed 13 in H20 (0.5 PSI) as pressure in excess of this could cause system components to perform inaccurately.

NOTE: A large difference between the vehicle temperature and shop temperature will seriously affect the accuracy of the tests. Always allow at least 15 min for the vehicle temperature to adjust to the shop temperature. Refer to Temperature Variation Instructions for more information about vehicle versus shop temperatures.

1. Engine OFF, open the hood. Position a large fan to blow air under the vehicle onto the fuel tank area.

2. Connect the red battery clip from the tester to the positive battery terminal.

NOTE: The vehicle battery must be fully charged for optimum tester performance.

3. Connect the black battery clip from the tester to chassis ground.

Flow Meter Test - Leak Detection

CAUTION: Refer to Fuel and Evaporative Emission Hose/Pipe Connection Cleaning Caution.

1. Open the Nitrogen tank valve and turn the NITROGEN / SMOKE valve on the front control panel to NITROGEN.

2. Connect the hose to the correct test orifice on the bottom front of the tester. For orifice size, refer to the vehicle specific information found in service procedures for DTCs that relate to EVAP system leaks.

3. Press and release the remote switch to activate the tester.

NOTE: The tester will time out after about 15 min. You may press the remote switch to reactivate the tester as desired.

4. Position the sliding red flag on the flow meter to align with the floating indicator. When the red flag is set, press and release the remote switch to deactivate the tester.

5. Remove the hose from the test orifice and install the hose onto the vehicle. For proper connection location, and the special tool numbers for any adapters that may be required, refer to the service procedures for DTCs that relate to EVAP system leaks.

6. Ignition ON, seal the EVAP system per instructions in the service procedures for DTCs that relate to EVAP system leaks. Most systems can be sealed using a scan tool output control for the EVAP Vent Solenoid Valve, other systems require that the vent system be plugged.

NOTE:

• Larger volume fuel tanks, and/or those with lower fuel levels, may require several minutes to fill with nitrogen.
• Static buildup may cause the float indicator to stick. It may be necessary to tap on the flow meter to free up the float.
• If fuel level is 90% or greater it will take longer to fill the system with smoke because the fuel fill tube check valve will be closed and force any smoke to pass through the on-board refueling vapor recovery pipe and orifice.

7. Press and release the remote switch to activate the nitrogen flow and fill the system.

8. Verify the stable floating indicator position to the red flag.

• Above the red flag, result is unacceptable - fail

Go to the Smoke Procedure

• Go to next step: Below the red flag - pass. Test complete

9. Press and release the remote switch to deactivate the tester.

Smoke Procedure - Locate the Leak

NOTE: It is not recommended to use the tester in an outside repair bay area because wind and sunlight may affect temperature and your ability to see the smoke.

1. Turn OFF any fans that may cause air movement around or near the vehicle.

NOTE: Completely unwind the nitrogen/smoke hose from the bracket to optimize the tester's performance.

2. Connect the nitrogen/smoke hose to the vehicle as directed in the service procedures. Some vehicles require that the nitrogen/smoke hose be connected at the front of the EVAP system at the EVAP service port. An adapter may be necessary. Other vehicles require the connection be made at the rear of the system using an adapter at the fuel fill cap or capless fuel fill. Consult the service procedures for DTCs that relate to EVAP system leaks for vehicle specific instructions regarding connection location and adapters.

3. Open the Nitrogen tank valve and turn the nitrogen/smoke valve on the control panel to smoke.

NOTE: The remote switch operates on a push ON, push OFF fashion.

4. Press and release the remote switch to activate the tester and inject smoke into the EVAP system.

5. Verify smoke has filled the EVAP system by opening the system opposite the end where smoke is injected.

NOTE:

• When injecting smoke at the service port:
  • Vehicles with gas cap - remove fill cap
  • Vehicles with capless fuel fill - open flappers with CH- 44284-2 or GE-41415-60

    Until smoke is observed, then close the system and continue testing.

• If using a special tool fuel fill cap / capless fuel fill adapter at the filler neck, vent the system at the service port, with special tool EN-41413-VLV until smoke is observed then remove the vent fitting tool and close the system to continue with the test.

  Inject smoke in less than 2 min cycles for optimum tester performance.

6. Press and release the remote switch to deactivate the tester.

NOTE: For optimum visual smoke performance, deactivate the smoke flow and allow the system pressure to drop. Allowing the smoke to exit small holes at a low flow rate greatly enhances visibility.

7. Introduce smoke into the system for an additional 60 s. Continue introducing smoke at 15 s intervals, as necessary until leak source is identified.

8. Using a high-intensity white light, inspect the entire EVAP system path, and look for the source of the leak indicated by the exiting smoke.

• Smoke seen leaking

Repair or replace the affected component.

• Go to next step: No smoke seen leaking

9. All OK

Temperature Variation Instructions

The Concern

Ideal circumstances for conducting the EVAP flow meter test require equal temperatures between the Nitrogen gas and the vehicle EVAP system. Significant differences in temperature between them can result in a flow or pressure change during testing, causing misleading results. Typically, the evaporative emission system tester is stored indoors, approximately 21ºC (70ºF). Vehicles brought in for diagnosis may have an EVAP system at significantly different temperatures.

For Example

NOTE: With no temperature difference between the Nitrogen gas and EVAP system, the resulting vehicle EVAP system pressure will remain stable at 13 in. H2O (0.5 PSI) once pressurized, providing no leaks are present.

When the EVAP flow meter tests are performed with significant differences in temperature between the Nitrogen gas and the vehicle EVAP system, the following results can occur:

• An increase in flow during the flow meter test can be caused by a vehicle's warm EVAP system cooling down.
• A decrease in flow during the flow meter test can be caused by a vehicle's cool EVAP system warming up.

The Solution

When working on a vehicle with significant temperature differences between the vehicle EVAP system and the Nitrogen gas, allow the vehicle EVAP system temperature to stabilize as close as possible to the temperature of the Nitrogen gas before conducting the flow meter test.

Electronic Ignition System Diagnosis

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions

Circuit/System Description

For an overview of the component/system, refer to:Electronic Ignition System Description

The ECM controls the spark event for each cylinder through individual ignition coil control circuits.

When the ECM commands the ignition control circuit On, electrical current flows through the primary winding of the ignition coil, creating a magnetic field. When a spark event is requested, the ECM commands the ignition control circuit Off, interrupting current flow through the primary winding. The collapsing magnetic field created by the primary winding induces a high voltage in the secondary winding, which is connected to the spark plugs. The ignition system on this engine uses ignition coils with integrated power transistors.

Reference Information

Schematic Reference

Engine Controls Wiring Schematics (LTG)

Connector End View Reference

Component Connector End View Index and Inline Harness Connector End View Index

Electrical Information Reference

• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs

Scan Tool Reference

Control Module References

Special Tools

J-26792 Ignition Spark Tester

Equivalent regional tools: Special Tools (Diagnostic Tools) and Special Tools (Mechanical Tools)

Circuit/System Testing

NOTE: Do NOT perform this procedure unless directed here from the following diagnostic:

• DTC P0300-P0304
• Engine Cranks But Does Not Run

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off.

2. Disconnect the appropriate electrical connector:T8 Ignition Coil.

3. Test for less than 10 ohms between the test points: Ground circuit terminal 1/A & Ground

• If 10 ohms or greater.

1. Disconnect the ground connection: Ground terminal
2. Test for less than 2 ohms between the test points: Ground circuit terminal 1/A@Component harness & The other end of the circuit
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Repair the open/high resistance in the ground connection.

• Go to next step: If less than 10 ohms

4. Test for less than 10 ohms between the test points: Low Reference circuit terminal 2/B & Ground

• If 10 ohms or greater

1. Disconnect the electrical connector:K20 Engine Control Module
2. Test for less than 2 ohms between the test points: Low Reference circuit terminal 2/B@Component harness & The other end of the circuit
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Replace the component:K20 Engine Control Module

• Go to next step: If less than 10 ohms

5. Ignition - On / Vehicle - In Service Mode

6. Verify a test lamp turns On between the test points: Ignition circuit terminal 4/D & Ground

• If the test lamp does not turn On

1. Ignition/Vehicle - Off & Remove - Test lamp
2. Test for less than 2 ohms between the test points: Ignition circuit terminal 4/D@Component harness & Output terminal@Fuse
   • If 2 ohms or greater - Repair the open/high resistance in the circuit.
   • If less than 2 ohms - Verify the fuse is OK and there is voltage at the fuse.

• Go to next step: If the test lamp turns On

7. Test or replace the component:T8 Ignition Coil

Component Testing

With Special Tool

NOTE: Circuit/System Testing must be performed before proceeding with Component Testing.

1. Ignition/Vehicle - Off.

2. Remove the appropriate component:T8 Ignition Coil - Leave the electrical connector connected.

3. Install the special tool: J-26792 Ignition Spark Tester.

4. Engine - Running.

NOTE: An erratic or weak spark is considered a no spark condition.

5. Verify there is spark at the tool.

• If there is no spark

Test or replace the component: T8 Ignition Coil

• Go to next step: If there is spark

6. All OK.

Without Special Tool

1. Ignition/Vehicle - Off.

2. Swap the two components:T8 Ignition Coil - The original component that set the DTC & Another known good component from the vehicle.

3. Engine - Running.

4. Verify the scan tool parameter: Cylinder 1 - 4 Current Misfire Counter=Increments - At the original component location the DTC set.

• If the parameter value does not increment

Replace the component:T8 Ignition Coil - The original component that set the DTC

• Go to next step: If the parameter value increments

5. Refer to: Circuit/System Testing

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification

• Ignition Coil Replacement
• For control module replacement, programming, and setup refer to: Control Module References

Inspection/Maintenance System Check

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Description

Several states require that a vehicle pass on-board diagnostic (OBD) system tests and inspection/maintenance (I/M) emission inspections in order to renew license plates. This is accomplished by viewing the Inspection/Maintenance System Status or Data display on a scan tool.

Using a scan tool, the technician can observe the I/M status in order to verify that the vehicle meets the criteria that complies with the local area requirements.

While testing in the I/M System Status mode, some DTCs may occur that are called I/M Test DTCs. An I/M Test DTC is defined as a fault code that is currently commanding the malfunction indicator lamp (MIL) ON, and is stored in non-volatile memory. The intended use of this data is to prevent vehicles from passing I/M inspection without proper repair to the vehicle. These fault codes are not erasable from any scan tool command or by disconnecting power to the controller. I/M Test DTCs are supported by all emissions related electronic control units (ECUs), such as engine control modules (ECMs), transmission control modules (TCMs), fuel pump control modules (FPCMs), etc. An I/M Test DTC will not be stored or erased from the ECU except at the end of trip processing which occurs 5 s after ignition OFF.

Conditions for Updating the I/M System Status

NOTE: New vehicles may not report an Inspection/Maintenance System Check pass or fail status for certain post catalyst oxygen sensor or heated oxygen sensor 2 diagnostics prior to 700 miles. After replacing a catalytic converter on a vehicle with greater than 700 miles, it may require up to an additional 700 miles to prevent a false failure status.

Each system requires at least one, and sometimes several, diagnostic tests. The results of these tests are reported by a DTC. A system monitor is complete when either all of the DTCs comprising the monitor have Run and Passed, or any one of the DTCs comprising the monitor have illuminated the MIL. Once all of the tests are completed, the Inspection/Maintenance System Status or Data will indicate YES in the Completed or Value column.

For example, when the HO2S Heater Monitor indicates YES, either all of the oxygen sensor heater tests have passed or one of the tests has illuminated the MIL. If the vehicle has four heated oxygen sensors, either all four heater circuit tests have passed or one of the heater circuit tests has illuminated the MIL.

The Inspection/Maintenance System Status or Data will indicate NO under the Completed or Value column when any of the required tests for that system have not run. The following is a list of conditions that would set the Inspection/Maintenance System Status or Data indicator to NO:

• The vehicle is new from the factory and has not yet been driven through the necessary drive conditions to complete the tests.
• The battery has been disconnected or discharged below operating voltage.
• The control module power or ground has been interrupted.
• The control module has been reprogrammed.
• The control module DTCs have been cleared as part of a service procedure.

Conditions for Clearing I/M Test DTCs

1. Only the OBD II System can erase I/M Test DTCs. The OBD II system must determine that the malfunction that caused the I/M Test DTC to be stored is no longer present and is not commanding the MIL. Each of the following represents ways to clear an I/M Test DTC:

• If the MIL goes off due to 3 passing drive cycles, and the scan tool code clear is not used, the I/M Test DTC is erased at power down of the last drive cycle.
• If a scan tool code clear is used to turn OFF the MIL, the I/M Test DTC is not erased, therefore the DTC must PASS and not FAIL during the drive cycle. The I/M Test DTC is erased at power down of the drive cycle.
• If the controller is reflashed/reprogrammed, all I/M Test DTCs are erased.

2. For the OBD II System to run a single drive cycle for clearing an I/M Test DTC, all of the following conditions must occur:

• Cumulative time of engine run time greater than 600 s.
• Cumulative vehicle operation above 40 km/h (25 mph) over 300 s.
• Continuous vehicle idle greater than 30 s.
• Ignition OFF for 5 s to allow the code to clear.

Monitored Emission Control Systems

The OBD II system monitors all emission control systems that are on-board, but not all vehicles need every possible emission control system. For example, a vehicle may not be equipped with secondary air injection (AIR) or exhaust gas recirculation (EGR). The OBD II regulations require monitoring of the following; if equipped:

• The air conditioning system
• The catalytic converter efficiency
• Comprehensive component monitoring - Emission related inputs and outputs
• The evaporative emission (EVAP) system
• The fuel delivery system
• Heated catalyst monitoring
• Misfire monitoring
• The oxygen sensor system (O2S or HO2S)
• The oxygen sensor heater system (HO2S heater)

For the specific DTCs required for each system, refer to Inspection/Maintenance (I/M) System DTC Table. Systems such as misfire and comprehensive components may not be listed in a system status list.

These tests run continuously and do not require an I/M System Status indicator.

Diagnostic Aids

The Inspection/Maintenance System Status or Data display provides an indication of when the control module has completed the required tests. This does not necessarily mean that the test has passed, only that a decision was made. If the diagnostic fails, a DTC will indicate the failure. If a failure indication is present for a DTC associated with one of the I/M regulated systems, it may prevent other required tests from running. For example, a DTC for the control circuit of the EVAP purge solenoid may not be listed in the Inspection/Maintenance System DTC Table because it is a continuous test. If this DTC is set, the Active Tests for the EVAP system may not run.

The Inspection/Maintenance System Status or Data information may be useful for a technician to determine if diagnostics have run when verifying repairs.

Circuit/System Verification

Review the Inspection/Maintenance System Status or Data indicators. All Inspection/Maintenance System Status or Data indicators should report YES, and no I/M Test DTCs should be present.

Circuit/System Testing

NOTE: Many DTC related repairs will instruct the technician to clear the DTC information. Clearing the DTC will reset the Inspection/Maintenance System Status or Data indicators to NO.

Performing the I/M Complete System Set Procedure will set each of the I/M System Status indicators to YES.

1. Observe the Engine DTC information with a scan tool. Verify no DTCs are present.

• If a DTC is set that would prevent the I/M System Status tests from completing, diagnose that DTC before continuing. Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Review applicable service bulletins for software updates that would prevent the I/M System Status tests from completing.

• If a control module re-program or other repair is required, perform the Inspection/Maintenance Complete System Set Procedure.

3. Observe the Inspection/Maintenance System Status or Data indicators.

• If any Inspection/Maintenance System Status or Data indicators report NO, perform the Inspection/Maintenance Complete System Set Procedure.

4. Observe the I/M Test DTC information with a scan tool. Verify there are no I/M Test DTCs present.

• If an I/M Test DTC is set and all of the Inspection/Maintenance System Status or Data indicators are Yes, there is no need to perform the Complete System Set Procedure.

  Diagnose the DTC using the Diagnostic Trouble Code (DTC) List - Vehicle and refer to Conditions for Clearing the I/M Test DTCs.

• If an I/M Test DTC is set and the Inspection/Maintenance System Status or Data indicators are NO, diagnosis the DTC and perform the Inspection/Maintenance Complete System Set Procedure.

Inspection/Maintenance Complete System Set Procedure

Diagnostic Instructions

• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Description

The purpose of the Inspection/Maintenance Complete System Set Procedure is to satisfy the enable criteria necessary to execute all of the I/M readiness diagnostics and complete the drive cycles for those particular diagnostics. When all I/M monitored diagnostic tests are completed, the I/M System Status indicators are set to YES. Perform the Inspection/Maintenance Complete System Set Procedure if any I/M System Status indicators are set to NO.

Conditions for Meeting a Cold Start

• The ignition voltage between 11 - 18 V.
• The barometric pressure is more than 75 kPa (10.9 psi).
• The start-up engine coolant temperature (ECT) is between 4 - 30ºC (39 - 86ºF).
• The start-up intake air temperature (IAT) is between 4 - 30ºC (39 - 86ºF).
• The difference between the IAT and the ECT is less than or equal to 6ºC (43ºF).
• The ambient air temperature is between 4 - 30ºC (39 - 86ºF).
• The fuel level is between 15 - 85 %.

Circuit/System Verification

1. Verify that all I/M System Status indicators report YES, and that no I/M Test DTCs are present.

• If any I/M Test DTCs are set

Refer to Diagnostic Trouble Code (DTC) List - Vehicle.

• Go to next step: If no I/M Test DTCs are set

2. All OK.

Inspection/Maintenance System Set Procedure

NOTE: Whenever the ignition is turned ON, ignition positive voltage is supplied to the heated oxygen sensor (HO2S) heaters. After verifying the enable criteria, turn OFF the ignition for approximately 5 min to allow the sensors to cool before continuing with the test.

When the engine is started, DO NOT turn the engine OFF for the remaining portion of the set procedure.

1. Ensure that the vehicle meets the conditions for a cold start listed above.

2. The evaporative emission inspection/maintenance system status indicator should display YES.

• If the inspection/maintenance system status indicator displays NO, perform the Service Bay Test, if applicable. If the Service Bay Test is NOT available, it may take up to 6 drive cycles, with up to 17 h between drive cycles, for the inspection/maintenance system status indicator to transition to YES.

3. The O2S Heater inspection/maintenance system status indicator should display YES.

• If the O2S Heater inspection/maintenance system status indicator displays NO, ensure that the ignition has been turned OFF for at least 10 h.

4. Turn OFF all accessories; HVAC system, other electrical loads, including aftermarket/add-on equipment, etc.

5. Set the vehicle parking brake and ensure the vehicle is in Park for automatic transmission or Neutral for manual transmission.

6. Turn OFF all accessories; HVAC system, other electrical loads, including aftermarket/add-on equipment, etc.

7. Start and idle the engine for at least 2 min and until 65ºC (149ºF) is achieved.

8. Run the engine for 6.5 min within the following conditions:

• MAF parameter between 4 - 30 g/s
• Engine speed steady between 1, 000 - 3, 000 RPM

9. Return the engine to idle for 1 minute.

10. Apply and hold the brake pedal, and shift to Drive for automatic transmission, or apply the clutch pedal for manual transmission and operate the vehicle within the following conditions for 2 min:

• Depress the accelerator pedal until throttle position sensor angle is more than 2 %.
• Mass air flow signal between 15 - 30 g/s
• RPM steady between 1, 200 - 2, 000 RPM

NOTE: DO NOT touch the accelerator pedal during the idle period. A change in throttle position sensor angle or an increase in engine speed may invalidate this portion of the test.

11. Release the accelerator pedal and shift the vehicle to Park for automatic transmission, or Neutral and release the clutch pedal for manual transmission, and allow the engine to idle for 2 min.

12. Quickly depress the accelerator pedal until throttle position sensor angle is more than 8 % and return to idle, repeat 3 times.

13. Allow engine to idle for at least 2 min.

WARNING: Refer to Road Test Warning.

14. Release the parking brake and drive vehicle at 24 km/h (15 mph) or slower for 2 min.

15. Continue to drive the vehicle for at least 5.5 mi between 45 - 112 km/h (28 - 70 mph) with the vehicle reaching at least 80 km/h (50 mph).

16. Release the accelerator pedal for at least 2 s. This will allow the vehicle to enter decel fuel cut-off.

17. Depress the accelerator pedal until the throttle position sensor angle is increased 3 - 20 % and maintain a safe speed for 1 min.

18. Safely stop the vehicle, with the engine in Drive for automatic transmission or in Neutral with the clutch pedal depressed and parking brake applied for manual transmission, idle for 2 min.

19. Shift to Park for automatic and apply the parking brake, or neutral and release clutch pedal for manual.

NOTE: DO NOT disturb the vehicle or turn ON the ignition until told to do so. Disturbing the vehicle may invalidate this portion of the test.

20. Turn OFF the ignition and exit the vehicle. Do NOT disturb the vehicle for 60 min.

21. Observe the Inspection/Maintenance System Status with a scan tool. All of the Inspection/Maintenance System Status indicators should display YES.

• If the evaporative emission Inspection/Maintenance System Status indicator displays NO, turn OFF the ignition for 17 h, ensure that the vehicle meets the conditions for a cold start, and repeat steps 12 - 18 six more times, or until the evaporative emission Inspection/Maintenance System Status indicator transitions to YES. If the indicator continues to display NO, refer to the Inspection/Maintenance (I/M) System DTC Table to identify the DTCs that did not run. Follow the Conditions for Running the DTC in order to set the evaporative emission Inspection/Maintenance System Status indicator
• If any of the Inspection/Maintenance System Status display NO, refer to the Inspection/Maintenance (I/M) System DTC Table for the indicator which did not display YES. The Inspection/Maintenance System DTC Table identifies the DTCs associated with each Inspection/Maintenance System Status Indicator. Follow the Conditions for Running the DTC in order to set the associated status indicator.

NOTE: An I/M Test DTC will not be stored or erased from the ECU except at the end of trip processing which occurs 5 s after ignition OFF.

22. Observe the I/M Test DTC information with a scan tool. Verify there are no I/M Test DTCs present.

• If an I/M Test DTC is set, diagnose the DTC using the Diagnostic Trouble Code (DTC) List - Vehicle , and refer to Inspection/Maintenance System Check for clearing I/M Test DTCs.
• If an I/M Test DTC is set and the I/M System Status indicators are NO, diagnosis the DTC and perform the Inspection/Maintenance Complete System Set Procedure.

23. Observe the engine DTC information with a scan tool. Verify no DTCs are present.

• If a DTC is set, diagnose using the Diagnostic Trouble Code (DTC) List - Vehicle. After repairs, perform the Inspection/Maintenance Complete System Set Procedure to verify no further DTCs are set.

INSPECTION/MAINTENANCE (I/M) SYSTEM DTC TABLE

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