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Engine Control System - 5.3L - DTC P0451 to P1381: Overview GMC Envoy II

Testing & Diagnostics ~1469 words

DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTCDescription
P0451Fuel Tank Pressure (FTP) Sensor Performance
P0452Fuel Tank Pressure (FTP) Sensor Circuit Low Voltage
P0453Fuel Tank Pressure (FTP) Sensor Circuit High Voltage
P0454Fuel Tank Pressure (FTP) Sensor Circuit High Voltage
P0455Evaporative Emission (EVAP) System Large Leak Detected
P0496Evaporative Emission (EVAP) System Flow During Non-Purge
P0506Idle Speed Too Low
P0507Idle Speed High
P0556Brake Booster Pressure Sensor Performance
P0557Brake Booster Pressure Sensor Circuit Low Voltage
P0558Brake Booster Pressure Sensor Circuit High Voltage
P0601Control Module Read Only Memory (ROM)
P0602Control Module Not Programmed
P0603Control Module Long Term Memory Reset
P0604Control Module Random Access Memory (RAM)
P0606Control Module Internal Performance
P0607Control Module Performance
P060DControl Module Accelerator Pedal Position (APP) System Performance
P060EControl Module Throttle Position (TP) System Performance
P06415-Volt Reference 1 Circuit
P0650Malfunction Indicator Lamp (MIL) Control Circuit
P06515-Volt Reference 2 Circuit
P0685Engine Controls Ignition Relay Control Circuit
P0689Engine Controls Ignition Relay Feedback Circuit Low Voltage
P0690Engine Controls Ignition Relay Feedback Circuit High Voltage
P0700Transmission Control Module (TCM) Requested MIL Illumination
P1101Intake Air Flow System Performance
P1133HO2S Insufficient Switching Bank 1 Sensor 1
P1134HO2S Transition Time Ratio Bank 1 Sensor 1
P1153HO2S Insufficient Switching Bank 2 Sensor 1
P1154HO2S Transition Time Ratio Bank 2 Sensor 1
P1380Misfire Detected - Rough Road Data Not Available
P1381Misfire Detected - No Communication With Brake Control Module
P1621Control Module Long Term Memory Performance
P2610Control Module Ignition OFF Timer Performance

DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

System Description

The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the evaporative emission (EVAP) system. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies, depending on EVAP system pressure or vacuum. The controller uses this FTP signal to determine atmospheric pressure for use in the engine-off small leak test, P0442. Before using this signal as an atmospheric reference, it must first be re-zeroed. If the FTP signal is out of range during the re-zero procedure, this DTC will set.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. 4: This step tests for the signal voltage that represents atmospheric pressure. Removing the fuel fill cap ensures a vented EVAP system. Record the value for possible use later in the diagnostic table.
  2. 5: This step tests the accuracy of the FTP sensor by comparing the electrical signal value to the EEST mechanical gage value.
  3. 8: A restricted EVAP system will not allow the nitrogen to flow freely through the system. A restriction will cause the FTP signal voltage parameter to decrease as the pressure builds.
StepActionValuesYesNo
Schematic Reference: Evaporative Emissions (EVAP) Hose Routing Diagram and Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2Is DTC P0446, P0452, P0453, or P0651 also set?Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC InformationGo to Step 3
3Inspect the evaporative emission (EVAP) system for the following conditions: A damaged EVAP canister vent solenoid valve-Refer to Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement . A pinched EVAP hose A damaged EVAP canister-Refer to Evaporative Emission (EVAP) Canister Replacement (TrailBlazer, Envoy, Rainier) Evaporative Emission (EVAP) Canister Replacement (TrailBlazer EXT, Envoy XL, Envoy XUV) . Did you find and correct the condition?Go to Step 17Go to Step 4
4Remove the fuel fill cap. Turn ON the ignition, with the engine OFF. Observe and record the fuel tank pressure (FTP) parameter in volts with a scan tool. Is the fuel tank pressure sensor parameter within the specified amount?1.3-1.7 VGo to Step 5Go to Step 14
5IMPORTANT: Ensure that the vehicle underbody temperature is similar to the ambient temperature. Turn OFF the ignition. Install the fuel fill cap. Connect the J 41413-200 Evaporative Emission System Tester (EEST) power supply clips to a known good 12-volt source. Install the J 41415-40 Fuel Tank Cap Adapter or the GE-41415-50 Fuel Cap Adapter to the fuel fill pipe. Connect the J 41413-200 NITROGEN/SMOKE supply hose to the J 41415-40 or the GE-41415-50 to the fuel fill pipe. Turn the ignition ON, with the engine OFF. Turn the NITROGEN/SMOKE valve on the J 41413-200 to NITROGEN. Using a scan tool PURGE/SEAL function, seal the EVAP system. Observe the fuel tank pressure sensor in H2O using a scan tool. Use a remote switch to pressurize the EVAP system to the first specified value. Allow at least 30 seconds for pressure in the EVAP system to stabilize. Compare the fuel tank pressure (FTP) parameter in H2O to the J 41413-200 VACUUM/PRESSURE gage. Is the difference between the FTP parameter on a scan tool and the VACUUM/PRESSURE gage on the J 41413-200 within the specified value?5 in H2O 1 in H2OGo to Step 6Go to Step 14
6Release the pressure on the EVAP system with the scan tool. Is the difference between the FTP parameter on the scan tool and the VACUUM/PRESSURE gage on the J 41413-200 within the specified value?1 in H2OGo to Step 7Go to Step 14
7Start the engine. Allow the engine to idle. IMPORTANT: Using more than 20 percent purge can cause a misdiagnosis. Use the PURGE/SEAL function of a scan tool to command 20 percent purge. Observe the VACUUM/PRESSURE gage on the J 41413-200 and the fuel tank pressure parameter on the scan tool. Allow the vacuum to increase to the first specified value. Is the difference between the FTP parameter on the scan tool and the VACUUM/PRESSURE gage on the J 41413-200 within the second specified value?5 in H2O 1 in H2OGo to Step 8Go to Step 14
8Turn ON the ignition, with the engine OFF. Turn the NITROGEN/SMOKE valve on the J 41413-200 to NITROGEN. Observe the FTP sensor in volts using a scan tool. Pressurize the EVAP system with the remote switch. Allow enough time for pressure to stabilize. Is the difference between the observed FTP sensor voltage and the voltage recorded in Step 4 more than the specified value?0.2 VGo to Step 9System OK
9Disconnect the EVAP vent hose from the EVAP canister vent solenoid valve with pressure still applied from the J 41413-200 . Refer to Evaporative Emissions (EVAP) Hose Routing Diagram . Observe the FTP sensor in volts using a scan tool. Is the difference between the observed FTP sensor voltage and the voltage recorded in Step 4 more than the specified value?0.2 VGo to Step 10Go to Step 11
10Disconnect the EVAP vapor pipe from the EVAP canister with pressure still applied from the J 41413-200 . Refer to Evaporative Emission (EVAP) Hoses/Pipes Replacement - Chassis . Observe the FTP sensor in volts using a scan tool. Is the difference between the observed FTP sensor voltage and the voltage recorded in Step 4 more than the specified value?0.2 VGo to Step 13Go to Step 12
11Repair or replace the EVAP canister vent solenoid. Refer to Evaporative Emission (EVAP) Canister Vent Solenoid Valve Replacement . Did you complete the action?Go to Step 17
12Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement (TrailBlazer, Envoy, Rainier) Evaporative Emission (EVAP) Canister Replacement (TrailBlazer EXT, Envoy XL, Envoy XUV) . Did you complete the replacement?Go to Step 17
13Repair or replace the pinched or restricted EVAP vapor pipe. Refer to Evaporative Emissions (EVAP) Hose Routing Diagram . Did you complete the action?Go to Step 17
14Test for an intermittent and for a poor connection at the FTP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition?Go to Step 17Go to Step 15
15Test the low reference circuit of the FTP sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition?Go to Step 17Go to Step 16
16Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement . Did you complete the replacement?Go to Step 17
17Reconnect all components and release any pressure or vacuum applied to the EVAP system. Turn ON the ignition, with the engine OFF. Observe and record the fuel tank pressure (FTP) parameter in H2O with a scan tool. Is the fuel tank pressure sensor parameter within the specified amount?1 to +1 in H2OGo to Step 18Go to Step 2
18Turn ON the ignition, with the engine OFF. Command the EVAP canister vent solenoid closed with a scan tool. Turn the NITROGEN/SMOKE valve on the J 41413-200 to NITROGEN. Pressurize the EVAP system to the first specified value with the remote switch. Observe the fuel pressure sensor in H2O using a scan tool. Command the EVAP canister vent solenoid valve open with a scan tool. Is the fuel tank pressure sensor parameter less than the second specified value?5 in H2O 1 in H2OGo to Step 19Go to Diagnostic Aids
19Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC InformationGo to Step 20
20IMPORTANT: The malfunction indicator lamp (MIL) may remain ON after the repair unless the DTCs are cleared. Clear the DTCs with a scan tool.Did you complete the action?System OK
IMPORTANT
Ensure that the vehicle underbody temperature is similar to the ambient temperature.
IMPORTANT
Using more than 20 percent purge can cause a misdiagnosis.
IMPORTANT
The malfunction indicator lamp (MIL) may remain ON after the repair unless the DTCs are cleared.

DTC P0451

The number below refers to the step number on the diagnostic table.

  1. 5: This step tests for the proper operation of the circuit in the high voltage range.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Idle the engine for one minute. Monitor the DTC information with a scan tool. Did DTC P0641 or P0651 fail this ignition?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3Observe the fuel tank pressure sensor parameter with the scan tool. Does the scan tool indicate that fuel tank pressure sensor parameter is less than the specified value?0.1 VGo to Step 5Go to Step 4
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Turn ON the ignition, with the engine OFF. 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. Did the DTC fail this ignition?Go to Step 5Go to Testing for Intermittent Conditions and Poor Connections
5Turn OFF the ignition. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Disconnect the fuel tank wiring harness at the fuel tank harness connector. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the fuel tank pressure (FTP) sensor and the signal circuit of the FTP sensor. Turn ON the ignition, with the engine OFF. Observe the fuel tank pressure sensor voltage with a scan tool. Is the fuel tank pressure sensor parameter more than the specified value?4.8 VGo to Step 8Go to Step 6
6Test the 5-volt reference circuit of the FTP sensor for an open between the fuel tank harness connector and the control module. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 12Go to Step 7
7Test the signal circuit of the FTP sensor for a short to ground, or an open between the fuel tank harness connector and the control module. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 12Go to Step 9
8Remove the fuel tank. Refer to Fuel Tank Replacement (TrailBlazer EXT, Envoy XL, Envoy XUV) or Fuel Tank Replacement (TrailBlazer, Envoy, Rainier) . Inspect the fuel tank wiring harness for the following: Damaged wiring Poor connections Broken wires inside the insulation-Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 12Go to Step 10
9Inspect for poor connections at the harness connector of the control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 12Go to Step 11
10Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement . Did you complete the replacement?Go to Step 12
11Replace the engine control module (ECM). Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 12
12Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Turn ON the ignition, with the engine OFF. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 13
13Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0452

The number below refers to the step number on the diagnostic table.

  1. 2: If DTC P0641 or P0651 is set, the 5-volt reference circuit may be shorted to a voltage.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Idle the engine for one minute. Monitor the DTC information with the scan tool. Did DTC P0641 or P0651 fail this ignition?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3Turn ON the ignition, with the engine OFF. Observe the fuel tank pressure sensor voltage with a scan tool. Is the fuel tank pressure sensor parameter more than the specified value?4.3 VGo to Step 5Go to Step 4
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Turn ON the ignition, with the engine OFF. 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. Did the DTC fail this ignition?Go to Step 5Go to Testing for Intermittent Conditions and Poor Connections
5Turn OFF the ignition. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle . Disconnect the fuel tank wiring harness at the fuel tank harness connector. Turn ON the ignition, with the engine OFF. Observe the fuel tank pressure (FTP) sensor voltage with a scan tool. Does the scan tool indicate that the fuel tank pressure sensor parameter is more than the specified value?1 VGo to Step 6Go to Step 7
6Test the signal circuit of the FTP for a short to voltage between the fuel tank harness connector and the control module. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 13Go to Step 12
7Probe the low reference circuit of the FTP sensor at the fuel tank harness connector with a test lamp connected to battery voltage. Refer to Circuit Testing . Did the test lamp illuminate?Go to Step 9Go to Step 8
8Test the low reference circuit of the FTP sensor for an open between the fuel tank harness connector and the control module. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 13Go to Step 10
9Remove the fuel tank. Refer to Fuel Tank Replacement (TrailBlazer EXT, Envoy XL, Envoy XUV) or Fuel Tank Replacement (TrailBlazer, Envoy, Rainier) . Disconnect the FTP sensor harness connector. Inspect the fuel tank wiring harness for the following: Damaged wiring Poor connections Broken wires inside the insulation-Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 13Go to Step 11
10Inspect for poor connections at the harness connector of the control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 13Go to Step 12
11Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement . Did you complete the replacement?Go to Step 13
12Replace the engine control module (ECM). Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 13
13Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Turn ON the ignition, with the engine OFF. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 14
14Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0453

The fuel tank pressure (FTP) sensor measures air pressure or vacuum in the evaporative emission (EVAP) system. The control module supplies a 5-volt reference and a low reference circuit to the FTP sensor. The FTP sensor signal voltage varies depending on EVAP system pressure or vacuum. The controller uses this FTP signal to determine atmospheric pressure for use in the engine OFF small leak test, P0442. This DTC will set if the control module detects an intermittent signal from the FTP that would prevent the engine-off small leak test, P0442, from running.

The number below refers to the step number on the diagnostic table.

  1. 3: Sealing the system will allow normal pressure in the EVAP system to preload the sensor. This will help put the sensor in a range that is more sensitive, making the test more accurate.
StepActionYesNo
Schematic Reference: Evaporative Emissions (EVAP) Hose Routing Diagram and Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Are DTCs P0442, P0446, P0452, P0453, or P0651 also set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3Inspect for an intermittent and for a poor connection at the fuel tank pressure (FTP) sensor. Refer to Testing for Intermittent Conditions and Poor Connections . Did you find and correct the condition?Go to Step 5Go to Step 4
4Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement . Did you complete the replacement?Go to Step 5
5Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0454

The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve open and the EVAP canister vent solenoid valve closed. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister purge and vent solenoid valves.

Control Module CommandEVAP Canister Purge Solenoid ValveEVAP Canister Vent Solenoid Valve
ONOpenClosed
OFFClosedOpen

DTC P0455

The numbers below refer to the step numbers on the diagnostic table.

  1. 4: Introducing smoke in 15 second intervals may allow smaller leak areas to be more noticeable. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
  2. 6: This step verifies proper operation of the FTP sensor.
  3. 7: A normal operating FTP sensor should increase above 5 inches of H2O and stop between 6-7 inches of H2O.
StepActionValuesYesNo
Schematic Reference: Evaporative Emissions (EVAP) Hose Routing Diagram
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Inspect the evaporative emission (EVAP) system for the following conditions: Loose, missing, or damaged service port Schrader valve Loose, incorrect, missing, or damaged fuel fill cap A damaged EVAP canister purge solenoid valve Raise the vehicle on a hoist. Refer to Lifting and Jacking the Vehicle . Inspect the EVAP system for the following conditions: Disconnected, improperly routed, kinked, or damaged EVAP pipes and hoses A damaged EVAP canister vent solenoid valve or EVAP canister Did you find and correct the condition?Go to Step 21Go to Step 3
3Turn OFF the ignition. Connect the J 41413-200 Evaporative Emissions System Tester (EEST) power supply clips to a known good 12-volt source. Turn the nitrogen/smoke valve to NITROGEN. Connect the nitrogen/smoke hose to the 0.5 mm (0.20 in) test orifice on the bottom-front of the J 41413-200 . Use the remote switch to activate the J 41413-200 . Align the red flag on the flow meter with the floating indicator. Use the remote switch to de-activate the J 41413-200 . Install the J 41415-40 Fuel Tank Cap Adapter to the fuel fill pipe. Install the fuel fill cap to the J 41415-40 . Remove the nitrogen/smoke hose from the test orifice and install the hose onto the J 41415-40 . Turn ON the ignition, with the engine OFF. Command the EVAP canister vent solenoid valve CLOSED, with a scan tool. Use the remote switch to introduce nitrogen and fill the EVAP system until the floating indicator stabilizes. Compare the flow meter's stable floating indicator position to the red flag. Is the floating indicator below the red flag?Go to Step 6Go to Step 4
4IMPORTANT: Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. System flow will be less with higher temperatures. Turn OFF the ignition. Connect the J 41413-200 power supply clips to a known good 12-volt source. Install the J 41415-40 or GE-41415-50 Fuel Tank Cap Adapter to the fuel fill pipe. Connect the J 41413-200 nitrogen/smoke supply hose to the J 41415-40 or GE-41415-50 . Turn ON the ignition, with the engine OFF Command the EVAP canister vent solenoid valve closed with a scan tool. Turn the nitrogen/smoke valve on the J 41413-200 control panel to SMOKE. Use the remote switch to introduce smoke into the EVAP system. Use the J 41413-VLV EVAP Service Port Vent Fitting to open the EVAP service port. Remove the J 41413-VLV once smoke is observed. Continue to introduce smoke into the EVAP system for an additional 60 seconds. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT High Intensity White Light. Continue to introduce smoke at 15 second intervals until the leak source has been located. Did you locate and repair a leak source?Go to Step 21Go to Step 5
5Disconnect the J 41415-40 or GE-41415-50 from the fuel fill pipe. Install the fuel fill cap to the fuel fill pipe. Connect the J 41413-200 nitrogen/smoke supply hose to the EVAP service port. Use the remote switch to introduce smoke into the EVAP system. Inspect the entire EVAP system for exiting smoke with the J 41413-SPT . Continue to introduce smoke at 15 second intervals until the leak source has been located. Did you locate and repair a leak source?Go to Step 21Go to Step 6
6Use the remote switch to stop introducing smoke. Install the J 41415-40 or GE-41415-50 to the fuel fill pipe. Connect the J 41413-200 nitrogen/smoke supply hose and vehicle fuel fill cap to the J 41415-40 or GE-41415-50 . Command the EVAP canister vent solenoid valve open with a scan tool. Compare the fuel tank pressure sensor parameter with a scan tool to the J 41413-200 pressure/vacuum gage. Is the difference between the 2 gages less than the specified value?1 in H2OGo to Step 7Go to Step 14
7Seal the EVAP system using the EVAP Purge/Seal function with a scan tool. Turn the nitrogen/smoke valve on the J 41413-200 control panel to NITROGEN. Use the J 41413-200 to pressurize the EVAP system to the first specified value. Is the fuel tank pressure sensor parameter more than the second specified value?13 in H2O 5 in H2OGo to Step 8Go to Step 14
8Stop introducing nitrogen into the EVAP system with the remote switch. Increase the EVAP canister purge solenoid valve to 100 percent. Is the fuel tank pressure sensor parameter less than the specified value?1 in H2OGo to Step 9Go to Step 11
9Connect the nitrogen/smoke hose to the EVAP service port. Remove the J 41415-40 or GE-41415-50 . Install the fuel fill cap to the fuel fill pipe. Start the engine. Allow the engine to idle. Use the purge/seal function to seal the system, with a scan tool. Command the EVAP purge solenoid valve to 30 percent. Observe the vacuum/pressure gage on the J 41413-200 and the FTP parameter on the scan tool. Use the purge/seal function to seal the system, with a scan tool. Is the difference between the FTP parameter on a scan tool and the vacuum/pressure gage on the J 41413-200 within the specified value, until the vacuum reached the abort limit on the scan tool?1 in H2OGo to Step 10Go to Step 14
10Did the FTP parameter on a scan tool display more than the specified value?3.2 VGo to Diagnostic AidsGo to Step 17
11Disconnect the EVAP purge pipe from the EVAP canister purge solenoid valve. Is the fuel tank pressure sensor parameter less than the specified value?1 in H2OGo to Step 18Go to Step 12
12Disconnect the EVAP purge pipe at the EVAP canister. Is the fuel tank pressure sensor parameter less than the specified value?1 in H2OGo to Step 19Go to Step 13
13Disconnect the EVAP vapor pipe at the EVAP canister. Is the fuel tank pressure sensor parameter less than the specified value?1 in H2OGo to Step 20Go to Step 16
14Test for an intermittent and for a poor connection at the fuel tank pressure (FTP) sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 21Go to Step 15
15Test the low reference circuit of the FTP sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 21Go to Step 17
16Repair the pinched or obstructed EVAP vapor pipe. Did you complete the repair?Go to Step 21
17Replace the FTP sensor. Refer to Fuel Tank Pressure Sensor Replacement . Did you complete the replacement?Go to Step 21
18Replace the EVAP canister purge solenoid valve. Refer to Evaporative Emission (EVAP) Canister Purge Solenoid Valve Replacement . Did you complete the replacement?Go to Step 21
19Repair the restriction in the EVAP purge pipe. Refer to Evaporative Emission (EVAP) Hoses/Pipes Replacement - Chassis . Did you complete the repair?Go to Step 21
20Replace the EVAP canister. Refer to Evaporative Emission (EVAP) Canister Replacement (TrailBlazer, Envoy, Rainier) Evaporative Emission (EVAP) Canister Replacement (TrailBlazer EXT, Envoy XL, Envoy XUV) . Did you complete the replacement?Go to Step 21
21IMPORTANT: DO NOT exceed the specified value in this step. Exceeding the specified value may produce incorrect test results. Connect the J 41413-200 to the fuel fill pipe. Turn the nitrogen/smoke valve to NITROGEN. Seal the EVAP system using the EVAP Purge/Seal function with a scan tool. Pressurize the EVAP system to the specified value. Observe the J 41413-200 pressure/vacuum gage for 5 minutes. Does the J 41413-200 pressure/vacuum gage remain constant?5 in H2OGo to Step 22Go to Step 3
22Observe the fuel tank pressure sensor parameter with a scan tool. Is the scan tool fuel tank pressure parameter within the specified value of the J 41413-200 pressure/vacuum gage?1 in H2OGo to Step 23Go to Step 6
23Observe the J 41413-200 pressure/vacuum gage. Increase the EVAP canister purge solenoid valve to 100 percent. Does the pressure decrease?Go to Step 24Go to Step 11
24Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Ensure that the vehicle underbody temperature is similar to the ambient temperature and allow the surrounding air to stabilize before starting the diagnostic procedure. System flow will be less with higher temperatures.
IMPORTANT
DO NOT exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.

DTC P0455

This DTC tests for undesired intake manifold vacuum flow to the Evaporative Emission (EVAP) System. The control module seals the EVAP system by commanding the EVAP canister purge solenoid valve Closed and the EVAP canister vent solenoid valve Closed. The control module 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 canister purge and vent solenoid valves.

Control Module CommandEVAP Canister Purge Solenoid ValveEVAP Canister Vent Solenoid Valve
ONOpenClosed
OFFClosedOpen

DTC P0496

The number below refers to the step number on the diagnostic table.

  1. 2: This test determines whether the engine can achieve the commanded RPM. If the engine does not reach the commanded RPMs, the test determines whether the RPM is too high or too low.
StepActionYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Command the engine speed up to 1,500 RPM, down to 500 RPM, and up to 1,500 RPM, with a scan tool. Exit the engine speed control function. Does the engine speed correspond, within 100 RPM, with each command?Go to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 3
3Inspect for any condition that can reduce idle speed by increasing engine load. Examples include: Incorrect torque converter clutch (TCC) operation Accessories that require additional torque to operate Restricted exhaust Mechanical conditions that limit engine speed Did you complete the action?Go to Step 4
4Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 5
5Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0506

The number below refers to the step number on the diagnostic table.

  1. 2: This test determines whether the engine can achieve the commanded RPM. If the engine does not reach the commanded RPMs, the test determines whether the RPM is too high or too low.
StepActionYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Start the engine. Command the engine speed up to 1,500 RPM, down to 500 RPM, and up to 1,500 RPM with a scan tool. Exit the engine speed control function. Does the engine speed correspond, within 100 RPM, with each command?Go to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 3
3Inspect for the following conditions: Vacuum leaks Excessive deposits in the throttle body A faulty positive crankcase ventilation (PCV) valve Did you find and correct the condition?Go to Step 4
4Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 5
5Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0507

The numbers below refer to the step numbers on the diagnostic table.

  1. 6: The test lamp in this step is used to apply a load to the 5-volt reference circuit for the brake booster pressure sensor.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views and Engine Controls Connector End Views
1Did you perform the Vehicle System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Observe the brake booster pressure sensor voltage parameter with a scan tool. Is the brake booster pressure sensor voltage parameter less than the specified value?0.05 VGo to Step 4Go to Step 3
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Is the brake booster pressure sensor voltage parameter less than the specified value?0.05 VGo to Step 4Go to Intermittent Conditions
4Is DTC P0641 also set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 5
5Turn OFF the ignition. Disconnect the brake booster pressure sensor wire harness electrical connector. Test for shorted terminals and poor connections at the brake booster pressure sensor wire harness electrical connector and also the mating electrical connector on the brake booster pressure sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the conditionGo to Step 15Go to Step 6
6Turn ON the ignition with the engine OFF. Measure the voltage from the 5-volt reference circuit at the brake booster pressure sensor wire harness electrical connector to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.8-5.2 VGo to Step 7Go to Step 9
7Turn OFF the ignition. Connect one test lead of the DMM to the 5-volt reference circuit at the brake booster sensor wire harness electrical connector. Connect the other test lead of the DMM to a good ground. Configure the DMM to measure on the milliamps scale. Refer to Circuit Testing . Turn ON the ignition with the engine OFF. Is the amperage less than the specified value?174 mAGo to Step 9Go to Step 8
8Turn ON the ignition with the engine OFF. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the brake booster pressure sensor, and the signal circuit of the brake booster pressure sensor. Observe the brake booster pressure sensor voltage parameter with a scan tool. Is the brake booster pressure sensor voltage parameter within the specified range?4.8-5.2 VGo to Step 13Go to Step 10
9Test the brake booster pressure sensor 5-volt reference circuit for the following conditions: An open High resistance A short to ground Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 15Go to Step 12
10Test the brake booster pressure sensor signal circuit for the following conditions: An open High resistance A short to ground Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 15Go to Step 11
11Test the brake booster pressure sensor low reference circuit for the following conditions: An open High resistance Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 15Go to Step 12
12Test for shorted terminals and poor connections at the engine control module (ECM) wire harness electrical connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 15Go to Step 14
13Replace the brake booster pressure sensor. Refer to Brake Booster Vacuum Sensor Replacement . Did you complete the replacement?Go to Step 15
14Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 15
15Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 16
16Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0557

Description

This diagnostic applies to internal microprocessor integrity conditions within the engine control module (ECM). This diagnostic also addresses whether or not the ECM is not programmed.

The number below refers to the step number on the diagnostic table.

  1. 2: A DTC P0602 indicates the ECM is not programmed.
StepActionYesNo
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Is DTC P0602 set?Go to Step 3Go to Step 5
3Program the engine control module (ECM). Refer to Service Programming System (SPS) . Does DTC P0602 reset?Go to Step 4Go to Step 7
4Ensure that all tool connections are secure. Ensure that the programming equipment is operating correctly. Ensure that the correct software/calibration package is used. Attempt to program the ECM. Refer to Service Programming System (SPS) . Does DTC P0602 reset?Go to Step 5Go to Step 7
5Test all voltage and ground inputs to the ECM for an open circuit or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 7Go to Step 6
6Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 7
7Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Did the DTC fail this ignition?Go to Step 2Go to Step 8
8Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0601-P0607, P060E, P1600, P1621, P1627, P1681, P1683, or P2610

The numbers below refer to the step numbers on the diagnostic table.

  1. 2: A DTC P0602 indicates that the ECM is not programmed.
  1. 5: Resistance is measured at the pedal assembly because a pedal resistance that is lower than the specified value will set this DTC.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2Is DTC P0602 set?Go to Step 3Go to Step 5
3Program the engine control module (ECM). Refer to Service Programming System (SPS) in Programming and Setup. Does DTC P0602 reset?Go to Step 4Go to Step 8
4Ensure that all tool connections are secure. Ensure that the programming equipment is operating correctly. Ensure that the correct software/calibration package is used. Attempt to program the ECM. Refer to Service Programming System (SPS) in Programming and Setup. Does DTC P0602 reset?Go to Step 7Go to Step 8
5Turn OFF the ignition. Disconnect the accelerator pedal connector. Ensure that the pedal is at the rest position. Measure the resistance from the 5-volt reference of the accelerator pedal assembly to the accelerator pedal position (APP) sensor 2 signal of the accelerator pedal assembly with a DMM. Refer to Circuit Testing in Wiring Systems. Is the resistance less than the specified value?450 ohmGo to Step 6Go to Step 7
6Replace the accelerator pedal assembly. Refer to Accelerator Pedal Position (APP) Sensor Replacement . Did you complete the replacement?Go to Step 8
7Replace the ECM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement?Go to Step 8
8Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Did the DTC fail this ignition?Go to Step 2Go to Step 9
9Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC InformationSystem OK

DTC P060D

The number below refers to the step number on the diagnostic table.

  1. 9: A short to voltage on the signal circuit of the MAP and FTP sensors may backfeed through the sensor into the 5-volt reference circuit and set this DTC.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Does the DTC fail this ignition?Go to Step 3Go to Testing for Intermittent Conditions and Poor Connections
3Turn OFF the ignition. Disconnect the engine oil pressure (EOP) sensor. Turn ON the ignition, with the engine OFF. Measure the voltage from the 5-volt reference circuit of the EOP sensor to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.8-5.2 VGo to Step 4Go to Step 5
4Connect the EOP sensor. Disconnect the manifold absolute pressure (MAP) sensor. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.8-5.2 VGo to Testing for Intermittent Conditions and Poor ConnectionsGo to Step 10
5Is the voltage measured in step 3 more than the specified value?5.2 VGo to Step 8Go to Step 6
6Monitor the DMM while disconnecting all other sensors connected to this 5-volt reference bus, one at a time. Replace the component if the voltage returns to within the specified range when one of the above components is disconnected. Refer to the appropriate replacement procedure. Was a component replaced?4.8-5.2 VGo to Step 12Go to Step 7
7Test the 5-volt reference circuits of all the sensors connected to this 5-volt reference bus for a short to ground or any sensor low reference circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 12Go to Step 11
8IMPORTANT: If a short to voltage occurs, the A/C refrigerant pressure sensor may be damaged. Test the 5-volt reference circuits of all the sensors connected to this 5-volt reference bus for a short to voltage. Refer to Circuit Testing and Wiring Repairs .Did you find and correct the condition?Go to Step 12Go to Step 9
9IMPORTANT: If a short to voltage occurs on the MAP sensor signal circuit or fuel tank pressure (FTP) sensor signal circuit, the sensors may be damaged. Test the MAP sensor signal circuit and FTP sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .Did you find and correct the condition?Go to Step 12Go to Step 11
10Replace the EOP sensor. Refer to Engine Oil Pressure Sensor and/or Switch Replacement . Did you complete the replacement?Go to Step 12
11Replace the engine control module (ECM). Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 12
12Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 13
13Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
If a short to voltage occurs, the A/C refrigerant pressure sensor may be damaged.
IMPORTANT
If a short to voltage occurs on the MAP sensor signal circuit or fuel tank pressure (FTP) sensor signal circuit, the sensors may be damaged.

DTC P0641

The number below refers to the step number on the diagnostic table.

  1. 6: This step tests for a short to ground in the MIL control circuit. With the engine control module (ECM) disconnected and the ignition ON, the MIL should be OFF.
StepActionYesNo
Schematic Reference: Instrument Cluster Schematics or Engine Controls Schematics Connector End View Reference: Instrument Panel, Gages, and Console Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Command the malfunction indicator lamp (MIL) ON and OFF with a scan tool. Does the MIL turn ON and OFF when commanded with a scan tool?Go to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Does the DTC fail this ignition?Go to Step 4Go to Testing for Intermittent Conditions and Poor Connections
4Is the MIL always ON?Go to Step 6Go to Step 5
5Inspect the fuse that supplies voltage to the MIL. Is the fuse open?Go to Step 14Go to Step 7
6Turn OFF the ignition. Disconnect the engine control module (ECM). Turn ON the ignition. Is the MIL OFF?Go to Step 18Go to Step 11
7Turn OFF the ignition. Disconnect the ECM. Turn ON the ignition, with the engine OFF. Connect a 3-amp fused jumper wire between the MIL control circuit of the ECM and a good ground. Is the MIL illuminated?Go to Step 13Go to Step 8
8Did the fuse in the jumper wire open?Go to Step 16Go to Step 9
9Turn OFF the ignition. Remove the instrument panel cluster (IPC). Refer to Instrument Panel Cluster (IPC) Replacement . Turn ON the ignition, with the engine OFF. Probe the ignition 1 voltage supply circuit of the IPC harness connector with a test lamp that is connected to a good ground. Does the test lamp illuminate?Go to Step 10Go to Step 15
10Test the MIL control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct a condition?Go to Step 19Go to Step 12
11Test the MIL control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 19Go to Step 12
12Test for an intermittent and for a poor connection at the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 19Go to Step 17
13Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?Go to Step 19Go to Step 18
14Repair the short to ground in the voltage supply circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 19
15Repair the open in the ignition 1 voltage supply circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 19
16Repair the short to voltage in the MIL control circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 19
17Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement . Did you complete the replacement?Go to Step 19
18Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 19
19Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 20
20Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK

DTC P0650

The numbers below refer to the step numbers on the diagnostic table.

  1. 6: This step will determine if any mechanical faults have caused this DTC to set.
  2. 13: This voltage drop test will determine if high resistance has caused this DTC to set.
  3. 15: This step verifies the voltage signal from the ECM to the MAF sensor connector.
  4. 16: This step will determine if the ECM can accurately process the frequency signal that it receives from the MAF sensor.
  5. 17: This step will determine if an abnormal resistance of less than 1,150 ohms has skewed the MAF sensor frequency signal.
StepActionValuesYesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Control Module (ECM) Connector End Views or Engine Controls Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2IMPORTANT: A stalling condition created by any of the following DTCs may cause this DTC to set. Are DTCs P0121, P0641, P0651, P1516, P2101, P2119, or P2135 set?Go to Diagnostic Trouble Code (DTC) List - VehicleGo to Step 3
3IMPORTANT: This Diagnostic Routine may have to be followed more than once. This is because multiple failures cause DTC P1101 to set. Attempt to start the engine.Does the engine start?Go to Step 4Go to Step 5
4Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 60 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 5Go to Diagnostic Aids
5IMPORTANT: A malfunctioning displacement on demand (DOD) system may cause this DTC to set. Is DTC P1101 only set?Go to Displacement on Demand (DOD) System DiagnosisGo to Step 6
6Turn OFF the ignition. Inspect for the following conditions: A restricted or collapsed air intake duct A misaligned or damaged air intake duct A dirty or deteriorating air filter element Any objects blocking the air inlet probe of the mass air flow (MAF)/intake air temperature (IAT) sensor Any contamination or debris on the sensing elements in the probe of the MAF/IAT sensor Any water intrusion in the induction system Any vacuum leak downstream of the MAF/IAT sensor An intake manifold leak An engine misfire-Review the Freeze Frame/Failure records. A manifold absolute pressure (MAP) sensor seal that is missing or damaged A skewed or stuck engine coolant temperature (ECT) or IAT sensor-Refer to Temperature vs Resistance . Any type of restriction in the exhaust system-Refer to Restricted Exhaust . Did you find and correct the condition?Go to Step 25Go to Step 7
7IMPORTANT: The Altitude vs. Barometric Pressure (BARO) table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or temperature may cause a reading to be slightly out of range. Accurately determine the altitude. Turn ON the ignition, with the engine OFF. Observe the MAP Sensor kPa parameter with a scan tool. The MAP sensor pressure should be within the specified range for your altitude. Refer to Altitude vs Barometric Pressure . Is the MAP sensor pressure within the specified range as indicated on the Altitude vs. Barometric pressure table?Go to Step 8Go to DTC P0106
8Start the engine. Turn OFF all lights and accessories. Allow the engine to reach operating temperature. Observe the MAP Sensor parameter with a scan tool. Is the MAP Sensor parameter within the specified range?19-40 kPaGo to Step 9Go to DTC P0106
9Idle the engine. Take a snapshot of the Engine Data list while performing the following action. Refer to Scan Tool Snapshot Procedure . Increase the engine speed slowly to 3,000 RPM and then slowly back to idle. Exit from the snapshot and review the data. Observe the MAP Sensor kPa parameter frame by frame with a scan tool. Does the MAP Sensor parameter change smoothly and gradually through the specified range of the test?Go to Step 10Go to DTC P0106
10Turn OFF the ignition. Turn ON the ignition, with the engine OFF. Observe The TP Indicated Angle parameter with a scan tool. Depress the accelerator pedal completely. Is the TP Indicated Angle parameter within the specified range?99-100%Go to Step 11Go to DTC P1516
11Take a snapshot of the TAC Data list while performing the following action. Refer to Scan Tool Snapshot Procedure . Slowly depress the accelerator pedal to wide-open throttle and then slowly release the pedal. Exit from the snapshot and review the data. Compare the TP Sensor 1 and the TP Sensor 2 parameters frame by frame. Is the difference between the parameters at any time more than the specified value?3%Go to DTC P2135Go to Step 12
12Inspect the throttle body and the throttle valve for the following conditions: Any damage Any restriction that could affect the air flow through the throttle body or the throttle valve Any missing parts A throttle valve that is not fully open when the accelerator pedal is fully depressed Did you find and correct the condition?Go to Step 25Go to Step 13
13Measure the battery voltage with a DMM. Disconnect the MAF/IAT sensor. Connect a test lamp between the ignition 1 voltage circuit of the MAF sensor and a good ground. Refer to Probing Electrical Connectors . Connect the DMM to the probe of the test lamp and a good ground. Refer to Measuring Voltage Drop and Circuit Testing . Is the voltage within 0.50 volts of the specified value?B+Go to Step 14Go to Step 21
14IMPORTANT: All electrical components and accessories must be turned OFF. Turn OFF the ignition for 60 seconds to allow the control modules to power down. Measure the resistance from the ground circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing . Is the resistance less than the specified value?5 ohmGo to Step 15Go to Step 22
15Turn ON the ignition, with the engine OFF. Measure the voltage from the signal circuit of the MAF sensor to a good ground with a DMM. Refer to Circuit Testing . Is the voltage within the specified range?4.9-5.2 VGo to Step 16Go to Step 18
16Turn OFF the ignition. Connect the voltage supply and the ground lead of the J 38522 Variable Signal Generator to the vehicle. See Special Tools . Connect the red lead of the J 38522 to the signal circuit of the MAF sensor. See Special Tools . Refer to Probing Electrical Connectors . Set the Duty Cycle switch of the J 38522 to Normal. See Special Tools . Set the Frequency switch of the J 38522 to 5 K. See Special Tools . Set the Signal switch of the J 38522 to 5 V. See Special Tools . Start the engine and allow it to idle. Observe the MAF Sensor parameter with a scan tool. Is the MAF Sensor parameter within the specified range?4,950-5,025 HzGo to Step 17Go to Step 18
17IMPORTANT: The J 38522 is able to overcome an abnormal resistance on the signal circuit of up to 1,150 ohms. See Special Tools . The MAF sensor will not be able to overcome a resistance this high. Turn OFF the ignition. Disconnect the engine control module (ECM). Test the MAF sensor signal circuit for the following conditions: A high resistance IMPORTANT: The following short will skew the MAF sensor reading by 35 g/s or more at a wide-open throttle (WOT) acceleration. A short to the IAT signal circuit Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 25Go to Step 19
18Turn OFF the ignition. Disconnect the ECM. Test the MAF sensor signal circuit for the following conditions: A high resistance An intermittent open circuit A high resistance short to ground A short to the IAT signal circuit Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?Go to Step 25Go to Step 20
19Test for an intermittent and for a poor connection at the MAF/IAT sensor. Refer to Testing for Intermittent Conditions and Poor Connections , Connector Repairs and Repairing Connector Terminals . Did you find and correct the condition?Go to Step 25Go to Step 23
20Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections , Connector Repairs , and Repairing Connector Terminals . Did you find and correct the condition?Go to Step 25Go to Step 24
21Repair the high resistance or the intermittent open in the MAF sensor ignition 1 voltage circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 25
22Repair the high resistance or the intermittent open in the MAF sensor ground circuit. Refer to Wiring Repairs . Did you complete the repair?Go to Step 25
23Replace the MAF/IAT sensor. Refer to Mass Air Flow (MAF)/Intake Air Temperature (IAT) Sensor Replacement . Did you complete the replacement?Go to Step 25
24Replace the ECM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?Go to Step 25
25IMPORTANT: This diagnostic routine may have to be followed more than once. Clear the DTCs with a scan tool. Turn OFF the ignition for 60 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 26
26Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
A stalling condition created by any of the following DTCs may cause this DTC to set.
IMPORTANT
This Diagnostic Routine may have to be followed more than once. This is because multiple failures cause DTC P1101 to set.
IMPORTANT
A malfunctioning displacement on demand (DOD) system may cause this DTC to set.
IMPORTANT
The Altitude vs. Barometric Pressure (BARO) table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or temperature may cause a reading to be slightly out of range.
IMPORTANT
All electrical components and accessories must be turned OFF.
IMPORTANT
The J 38522 is able to overcome an abnormal resistance on the signal circuit of up to 1,150 ohms. See Special Tools . The MAF sensor will not be able to overcome a resistance this high.
IMPORTANT
The following short will skew the MAF sensor reading by 35 g/s or more at a wide-open throttle (WOT) acceleration.
IMPORTANT
This diagnostic routine may have to be followed more than once.

DTC P1101

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage is varying above and below the specified value, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. Observe the affected heated oxygen sensor (HO2S) voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?250-625 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Intermittent Conditions
4Turn OFF the ignition. Disconnect the affected HO2S. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 6Go to Step 5
5Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 8Go to Step 7
6Test the HO2S high signal circuit for a short to the HO2S low signal circuit. Refer to the following in Wiring Systems: Circuit Testing Wiring Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 14Go to Step 11
7Test the HO2S high signal circuit for an open or high resistance. Refer to the following in Wiring Systems: Circuit Testing Wiring Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 14Go to Step 11
8Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 10Go to Step 9
9Test the HO2S low signal circuit for an open or high resistance. Refer to the following in Wiring Systems: Circuit Testing Wiring Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 14Go to Step 11
10Test for shorted terminals and for poor connections at the HO2S. Refer to the following in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 14Go to Step 12
11Test for shorted terminals and for poor connections at the engine control module (ECM). Refer to the following in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 14Go to Step 13
12NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice in Cautions and Notices. IMPORTANT: The HO2S may be damaged due to contamination. Prior to replacing the HO2S, inspect for the following sources of contamination: A silicon contaminated HO2S Fuel contamination-Refer to Fuel System Diagnosis . Engine oil consumption-Refer to Oil Consumption Diagnosis in Engine Mechanical. Engine coolant consumption-Refer to Loss of Coolant in Engine Cooling. Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 .Did you complete the replacement?Go to Step 14
13Replace the engine control module (ECM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement?Go to Step 14
14Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 15
15Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC InformationSystem OK
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice in Cautions and Notices.
IMPORTANT
The HO2S may be damaged due to contamination. Prior to replacing the HO2S, inspect for the following sources of contamination

DTC P1133 or P1153

The number below refers to the step number on the diagnostic table.

  1. 2: If the voltage is varying above and below the specified value, the condition is not present.
StepActionValue(s)YesNo
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module (ECM) Connector End Views
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2Start the engine. Allow the engine to reach operating temperature. Refer to Scan Tool Data List . Operate the engine at 1,500 RPM for 30 seconds. Observe the affected heated oxygen sensor (HO2S) voltage parameter with a scan tool. Is the HO2S voltage parameter varying above and below the specified range?250-625 mVGo to Step 3Go to Step 4
3Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 4Go to Intermittent Conditions
4Turn OFF the ignition. Disconnect the affected HO2S. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and a good ground. Turn ON the ignition, with the engine OFF. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 6Go to Step 5
5Test the HO2S high signal circuit for an open or high resistance. Refer to the following in Wiring Systems: Circuit Testing Wiring Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 9
6Remove the jumper wire from the previous step. Connect a 3-amp fused jumper wire between the high signal circuit of the HO2S harness connector on the engine harness side and the low signal circuit of the HO2S harness connector on the engine harness side. Observe the HO2S voltage parameter with a scan tool. Is the HO2S voltage parameter less than the specified value?100 mVGo to Step 8Go to Step 7
7Test the HO2S low signal circuit for an open or high resistance. Refer to the following in Wiring Systems: Circuit Testing Wiring Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 9
8Test for shorted terminals and for poor connections at the HO2S. Refer to the following in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 10
9Test for shorted terminals and for poor connections at the engine control module (ECM). Refer to the following in Wiring Systems: Testing for Intermittent Conditions and Poor Connections Connector Repairs Heated Oxygen Sensor (HO2S) Wiring Repairs Did you find and correct the condition?Go to Step 12Go to Step 11
10NOTE: Refer to Silicon Contamination of Heated Oxygen Sensors Notice in Cautions and Notices. IMPORTANT: The HO2S may be damaged due to contamination. Prior to replacing the HO2S, inspect for the following sources of contamination: A silicon contaminated HO2S Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool) . Engine oil consumption-Refer to Oil Consumption Diagnosis in Engine Mechanical. Engine coolant consumption-Refer to Loss of Coolant in Engine Cooling. Replace the affected HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 .Did you complete the replacement?Go to Step 12
11Replace the engine control module (ECM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement?Go to Step 12
12Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. 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. Did the DTC fail this ignition?Go to Step 2Go to Step 13
13Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC InformationSystem OK
NOTE
Refer to Silicon Contamination of Heated Oxygen Sensors Notice in Cautions and Notices.
IMPORTANT
The HO2S may be damaged due to contamination. Prior to replacing the HO2S, inspect for the following sources of contamination

DTC P1134 or P1154

The engine control module (ECM) detects engine misfire events by monitoring variations in the crankshaft rotation speed. Wheel speed changes caused by rough road conditions can cause changes in crankshaft speed. By monitoring the wheel speed sensors, the anti-lock brake system (ABS) can determine if the vehicle is operating on a rough road. If the ABS is detecting a rough road condition severe enough to effect misfire detection, a rough road signal is sent to the ECM on the serial data circuit. If DTC P0300 is set and the rough road information is not available due to an ABS malfunction, DTC P1380 will set.

The engine control module (ECM) detects engine misfire events by monitoring variations in the crankshaft rotation speed. Wheel speed changes caused by rough road conditions can cause changes in crankshaft speed. By monitoring the wheel speed sensors, the anti-lock brake system (ABS) can determine if the vehicle is operating on a rough road. If the ABS is detecting a rough road condition severe enough to effect misfire detection, a rough road signal is sent to the ECM on the serial data circuit. If DTC P0300 is set and there is no communication with the brake control module, DTC P1381 will set.