Engine Control System - Self-Diagnostics - 4.2L: Diagnosis Oldsmobile Bravada III

ON-BOARD DIAGNOSTICS

PCM is equipped with a self-diagnostic system which detects system failures or abnormalities. When a malfunction occurs, PCM will store a Diagnostic Trouble Code (DTC) and, in most cases, illuminate the Malfunction Indicator Light (MIL) located on instrument cluster.

There are 2 paths for accessing on-board diagnostics. It is necessary to access information through both paths, as each path presents some different information.

1. Generic OBD-II This provides all generic codes and some OEM codes, serial data PIDs required for generic OBD-II and some OEM PIDs, monitor status, pending codes and freeze frame.
2. OEM All DTCs, all PIDs, failure records, enhanced scan tool information and all other OEM scanner functions.

Scan Tool Snapshot

The scan tool can be set up to take a snapshot of the parameters available via serial data. The snapshot function records live data over a period of time. The recorded data can be played back and analyzed. The scan tool can also graph parameters singly or in combinations of parameters for comparison. The snapshot can be triggered manually at the time the symptom is noticed, or set up in advance to trigger when a DTC sets. An abnormal value captured in the recorded data may point to a system or component that needs to be investigated further. Refer to the scan tool user instructions for more information on the Snapshot function.

DIAGNOSTIC PROCEDURE

Diagnosis of computerized engine control system should be performed in the following order

1. Ensure all engine systems not related to computer system are operating properly. DO NOT proceed with testing unless all other problems have been repaired. Diagnostic system check must be performed before using specific DTC testing procedure. See «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) .
2. If no DTCs are present and a driveability problem exists, see SYMPTOMS in appropriate TROUBLE SHOOTING - NO CODES article. Doing so will help identify proper system or component to check in appropriate SYSTEM & COMPONENT TESTING article.
3. After necessary repairs are made, clear DTCs, verify vehicle will enter "closed loop" operation and ensure DTC does not reset.

RETRIEVING DIAGNOSTIC TROUBLE CODES

DTCs are retrieved using a Tech 2 scan tool, or other OBD-II compatible scan tool connected to OBD-II 16-pin Data Link Connector (DLC). See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS. (Scheme 2) DLC is located below left side of dash.

Scheme 2

Diagnostic Procedures

Note. Do not perform this diagnostic if there is not a driveability concern, unless another procedure directs you to this diagnostic. Before you proceed with diagnosis, search for applicable service bulletins. Unless a diagnostic procedure instructs you, DO NOT clear the DTCs. If there is a condition with the starting system, see appropriate STARTERS article in STARTING & CHARGING SYSTEMS. Ensure the battery has a full charge. Ensure the battery cables are clean and tight. Ensure the PCM grounds are clean, tight, and in the correct location.

1. Install a scan tool. Does the scan tool turn ON? If yes, go to next step. If no, see SCAN TOOL DOES NOT POWER UP in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
2. Turn ON the ignition, with the engine OFF. Attempt to establish communication with the listed control modules. If you are using a Tech 2, obtain the information using the Class 2 Message Monitor feature: PCM. Vehicle Theft Deterrent (VTD). Instrument Panel (IP) cluster. Electronic Brake Control Module (EBCM). Heating, Ventilation, and Air Conditioning (HVAC). Does the scan tool communicate with all the listed control modules? If yes, go to next step. If no, see SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
3. Attempt to start the engine. Does the engine start and idle? If yes, go to next step. If no, see ENGINE CRANKS BUT DOES NOT RUN in appropriate TROUBLE SHOOTING - NO CODES article.
4. Select the DTC display function for the following control modules: PCM, VTD, IP Cluster, EBCM, HVAC. Does the scan tool display any DTCs? If yes, go to next step. If no, go to step 9 .
5. With a scan tool, select Captured Info in order to store the powertrain DTC information. Go to next step.
6. Does the scan tool display DTCs which begin with a "U"? If yes, see appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If no, go to next step.
7. Does the scan tool display DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 or P1683? If yes, see «DTC P0601-P0607, P1600, P1621, P1627, P1680, P1681 & P1683: PCM MEMORY»(ref-132531-S06484736482002012100000) under DIAGNOSTIC TESTS. If no, go to next step.
8. Does the scan tool display DTC P0562, P0563, P1621 or P1622? If yes, see appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS. If no, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) .
9. Is the customer's concern with the automatic transmission? If yes, see appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If no, go to next step.
10. Is the customer's concern with Inspection and Maintenance (I/M) testing? If yes, see «INSPECTION/MAINTENANCE SYSTEM CHECK»(ref-132531-S28661956892002012100000) under INSPECTION/MAINTENANCE PROCEDURES.
11. Review the following symptoms. Hard start, surges/chuggles, lack of power, sluggishness, sponginess, detonation/spark knock, hesitation, sag, stumble, cuts out, misses, poor fuel economy, poor fuel fill quality, rough, unstable, or incorrect idle and stalling, dieseling, run-on and backfire. See appropriate TROUBLE SHOOTING - NO CODES article. Did you find and correct the condition? If yes, system is okay. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) .

CLEARING DIAGNOSTIC TROUBLE CODES

There are 3 methods to clear DTCs.

Scan Tool

Scan tool is preferable way to clear DTC information. Freeze frame and failure record data will also be cleared. PCM adaptive learning and system monitors will only be cleared for those system which had a stored DTC.

SCAN TOOL USAGE

Scan tool is a specialized tester which, when connected to DLC, can be used to diagnose on-board computer control systems by providing instant access to circuit voltage information without need to crawl under dash or hood to backprobe sensors and connectors.

Scan tool reduces diagnostic time dramatically by furnishing input data (voltage signals) which can be compared to specification parameters. They may also furnish information on output device (solenoids and motors) status. However, status parameters only indicate output signals have been sent to devices by PCM; they do not indicate whether devices have responded properly to signal. Verify proper response at output device using a voltmeter or test light.

A problem may exist even if DTCs are not present. About 80 percent of driveability problems occur without setting DTCs. Sensors that are out of calibration will not set a DTC but will cause driveability problems.

Using a scan tool is the easiest method of checking sensor specifications and other data parameters. Scan tool is also useful in finding intermittent wiring problems by wiggling wiring harnesses and connections (key on, engine off) while observing data parameters.

Note. If erroneous voltage signals are suspected, verify tester information using a digital voltmeter and wiring schematic. If non-existent DTCs are displayed, DO NOT use scan tool for diagnosis. Contact tester manufacturer for additional information.

Scan Tool Display

Note. OBD-II vehicles have options available in the scan tool DTC mode to display enhanced information available. However, to fully utilize information and procedures requires the use of a Tech 2 scan tool. See scan tool operator's manual for additional information.

The following are Tech 2 scan tool sub-menus in the DTC INFO and SPECIFIC DTC modes

1. DTC INFO MODE Used to search for specific type of stored DTC information. There are 7 choices in this mode. Technician may be instructed to test DTCs in a certain manner. Follow the affected DTC test procedures. To get complete description of any status, hit ENTER key before pressing the desired "F" key.
2. DTC STATUS This selection will display any DTCs that have not run during the current ignition cycle or have reported a test failure during this ignition up to a maximum of 33 DTCs. A DTC test that runs and passes will cause affected DTC to be removed from scan tool screen.
3. FAIL THIS IGN. This selection will display all DTCs that have failed during the present ignition cycle.
4. HISTORY This selection will display only DTCs that are stored in the control module's history memory. It will not display type "D" DTCs. It will display all type "A" and type "B" DTCs that have the MIL illuminated and have failed within the last 40 warm-up cycles. It will also display type "C" DTCs that have failed within the 40 warm-up cycles.
5. LAST TEST FAIL This selection will only display DTCs that have failed the last time the test ran. If type "A" or "B" DTCs are displayed, the last test may have ran during the previous ignition cycle. For type "C" DTCs, the last failure must have occurred during the current ignition cycle to be displayed as LAST TEST FAIL.
6. MIL REQUEST This selection will only display DTCs that are requesting MIL illumination. Type "C" DTCs cannot be displayed using this option. This selection will report type "B" DTCs only after MIL illumination has been requested.
7. NOT RUN SCC Not Run Since Code Clear option will display up to 33 DTCs that have not run since DTCs were last cleared. Since any displayed DTCs have not run, their condition (passing or failing) is unknown.
8. TEST FAIL SCC Test Fail Since Code Clear selection will display all active and history DTCs that have reported a test failure since the last time DTCs were cleared. DTCs that last failed over 40 warm-up cycles before this option is selected will not be displayed.
9. FAILED SINCE CLEAR This message indicates the DTC has failed at least once within the last 40 warm-up cycles since the last time DTCs were cleared.
10. NOT RUN SINCE CL. Not Run Since Cleared message indicates that the selected diagnostic test has not run since the last time DTCs were cleared. Therefore, the diagnostic test status (passed or failed) is unknown. After DTCs are cleared, this message will continue to be displayed until the diagnostic test runs.
11. NOT RUN THIS IGN. Not Run This Ignition message indicates the selected diagnostic test has not run this ignition cycle.
12. TEST RAN AND PASSED This message indicates the selected diagnostic test has: Passed the last test. Ran and passed during this ignition cycle. Ran and passed since DTCs were last cleared. Test has not failed since DTCs were last cleared. If this message is displayed, repair is complete. If FAILED THIS IGN. message is displayed, repair is incomplete and further diagnosis is required.

Diagnostic Aids

The I/M System Status 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, the failure indication may prevent other required tests from running. For example, a DTC for the control circuit of the relay controlling an AIR pump may not be listed in the INSPECTION/MAINTENANCE SYSTEM DTCS table because this is a continuous test. If this DTC is set, the Active Tests for the AIR system may not run. The I/M System Status information may be useful for a technician to determine if diagnostics have run when verifying repairs.

Conditions for Running

Cold Start

1. The Barometric (BARO) pressure is more than 74 kPa.
2. The Engine Coolant Temperature (ECT) is below 86°F (30°C).
3. The Intake Air Temperature (IAT) is below 86°F (30°C).
4. The difference between the Intake Air Temperature (IAT) and the Engine Coolant Temperature (ECT) is 14°F (8°C) or less.
5. The battery voltage is between 9-18 volts.
6. The fuel level is between 1/4 and 3/4.

Rough road conditions may prevent some of the tests from running. Extreme high or low ambient temperatures may prevent tests such as Heated Oxygen Sensor (HO2S) Heater and Evaporative (EVAP) emission System from initiating. If a step is interrupted before completion, perform the remaining portion of the set procedures. Any portion of the set procedure that requires the engine at operating temperature may be repeated. This allows most of the diagnostics to run and the remaining tests can be performed using the individual System Set Procedures. If the vehicle has recently run, start this procedure at step 3 . This will allow the tests that require the engine at operating temperature to run. Using this method allows shorter cool down periods if the tests requiring a cold start do not initiate. The scan tool can be used to monitor each of the I/M System Status indicators during the I/M Complete System Set Procedure. When all of the indicators for a test step have updated to YES, testing can move on to the next step even if the remaining portion of the test is not complete. For example, step 3 is designed to run the EVAP, secondary Air Injection (AIR), and HO2S tests. The procedure instructs the technician to operate the vehicle in the enable conditions for 6 minutes. If all 3 tests have updated to YES within 4 minutes, it is not necessary to continue with the enable conditions and testing can advance to the next step.

INSPECTION/MAINTENANCE SYSTEM DTCS

1. The Barometric (BARO) pressure is more than 74 kPa.
2. The engine coolant is at operating temperature, 160-248°F (71-120°C).
3. The Intake Air Temperature (IAT) is between 5-167°F (-15-75°C).
4. The engine is in Closed Loop fuel control.
5. The engine has run for 6-8 minutes off idle in order to initiate test.
6. The battery voltage is between 11-18 volts.

The control module runs a maximum of 6 tests per trip until the Catalyst System Status updates to YES. If the status does not update, the test outlined in this procedure can be repeated until the I/M System Status updates to YES. The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the required tests have not run. When a failure occurs, the Emission Related DTC portion of the I/M System Status display will indicate the Malfunction Indicator Lamp (MIL) is requested. The I/M System Status also registers the number of diagnostic trouble codes (DTCs). The first failure of a type "B" DTC does not constitute a final determination of pass or fail, and will not update the I/M System Status to YES. A second trip is required, and all the conditions to run must be met in order for the test to run again. These conditions may include a partial to complete engine cool down. The I/M System Status will update only when an emission related DTC fails the second time, or when all of the tests pass. If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load, such as a cooling fan or an A/C compressor clutch turning ON, may cause the test to abort. If a diagnostic test is difficult to run, observe the I/M System Status display while maintaining the necessary enable conditions until the system status updates to YES.

Non Scan Tool Service Bay Test

1. The barometric pressure is more than 75 kPa.
2. The fuel level is between 1/4 and 3/4.
3. The battery voltage is between 10-18 volts.
4. The test will initiate only after a cold start. The control module considers the engine to be cold if the following conditions are met: The Engine Coolant Temperature (ECT) is between 39-86°F (3.8-30.0°C). The Intake Air Temperature (IAT) is between 39-86°F (3.8-30.0°C). The difference between the ECT and the IAT is less than 14°F (8°C).

Scan Tool Service Bay Test

1. The Barometric (BARO) pressure is more than 75 kPa.
2. The ECT is less than 176°F (80°C).
3. The fuel level is between 1/4 and 3/4.
4. The battery voltage is between 10-18 volts.

Extreme high or low ambient temperatures may prevent the EVAP System Tests from initiating. Performing a visual inspection prior to running the EVAP Service Bay Test may prevent having to repeat the test. A loose fuel cap may cause a Service Bay Test to abort or fail and prevent the I/M System Status from updating. A failed or aborted test will require the vehicle to cool down in order to meet the enable criteria to run another test. The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the required tests have not run. When a failure occurs, the Emission Related DTC portion of the I/M System Status display will indicate the Malfunction Indicator Lamp (MIL) is requested. The I/M System Status also registers the number of diagnostic trouble codes (DTCs). The first failure of a type "B" DTC does not constitute a final determination of pass or fail, and will not update the I/M System Status to YES. A second trip is required, and all the conditions to run must be met in order for the test to run again. These conditions may include a partial to complete engine cool down. The I/M System Status will update only when an emission related DTC fails the second time, or when all of the tests pass. If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load, such as a cooling fan or an A/C compressor clutch turning ON, may cause the test to abort. If a diagnostic test is difficult to run, observe the I/M System Status display while maintaining the necessary enable conditions until the system status updates to YES.

1. The Engine Coolant Temperature (ECT) is more than 135°F (57°C).
2. The engine is running in Closed Loop fuel control.
3. The engine has been running for more than 160 seconds.
4. The battery voltage is between 9-18 volts.

If the status does not update, the test outlined in this procedure can be repeated until the I/M System Status updates to YES. The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the required tests have not run. When a failure occurs, the Emission Related DTC portion of the I/M System Status display will indicate the Malfunction Indicator Lamp (MIL) is requested. The I/M System Status also registers the number of diagnostic trouble codes (DTCs). The first failure of a type "B" DTC does not constitute a final determination of pass or fail, and will not update the I/M System Status to YES. A second trip is required, and all the conditions to run must be met in order for the test to run again. These conditions may include a partial to complete engine cool down. The I/M System Status will update only when an emission related DTC fails the second time, or when all of the tests pass. If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load, such as a cooling fan or an A/C compressor clutch turning ON, may cause the test to abort. If a diagnostic test is difficult to run, observe the I/M System Status display while maintaining the necessary enable conditions until the system status updates to YES.

1. The start-up Engine Coolant Temperature (ECT) is less than 122°F (50°C).
2. The start-up Intake Air Temperature (IAT) is less than 122°F (50°C).
3. The difference between the IAT and the ECT is less than 14°F (8°C).
4. The battery voltage is between 11-18 volts.

The HO2S Heater Tests will normally run within the 2 minutes allotted in the procedure. If there is an indeterminate condition, the test may take up to 8 minutes on some vehicles before a decision of pass or fail is made. If the test does not update within the allotted period of time, continue operation within the enable conditions until the test updates to YES. If the test does not update to YES, it may have failed or aborted due to the loss of enabling conditions. Extremely high ambient temperatures may prevent the HO2S Heater Test from initiating. The I/M System Status does not indicate whether the test has passed or failed, only that a decision was made. When all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was made, even if all of the required tests have not run. When a failure occurs, the Emission Related DTC portion of the I/M System Status display will indicate the Malfunction Indicator Lamp (MIL) is requested. The I/M System Status also registers the number of diagnostic trouble codes (DTCs). The first failure of a type "B" DTC does not constitute a final determination of pass or fail, and will not update the I/M System Status to YES. A second trip is required, and all the conditions to run must be met in order for the test to run again. These conditions may include a partial to complete engine cool down. The I/M System Status will update only when an emission related DTC fails the second time, or when all of the tests pass. If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan tool data list and the service information for an indication of why the test does not complete. Some tests may abort due to changes in the conditions while the test is running. For example, changes in engine load, such as a cooling fan or an A/C compressor clutch turning ON, may cause the test to abort. If a diagnostic test is difficult to run, observe the I/M System Status display while maintaining the necessary enable conditions until the system status updates to YES.

DIAGNOSTIC TROUBLE CODE DEFINITIONS

DIAGNOSTIC TROUBLE CODE INDEX

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1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Inspect the fuse that supplies voltage to the MIL. Is the fuse open? If yes, go to step 10 . If no, go to next step.
3. Turn OFF the ignition. Disconnect the PCM. See «COMPONENT LOCATIONS»(ref-132531-S12736680062002012100000) . Turn ON the ignition, with the engine OFF. Connect a 3-amp fused jumper wire between the MIL control circuit and a good ground. Observe the MIL. Is the MIL illuminated? If yes, go to step 9 . If no, go to next step.
4. Did the fuse in the jumper wire open? If yes, go to step 11 . If no, go to next step.
5. Remove the Instrument Panel Cluster (IPC). See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Test the MIL control circuit for an open between the PCM and the IPC and repair as necessary. Did you find and correct the condition? If yes, go to step 14 . If no, go to next step.
6. Probe the MIL battery positive voltage circuit at the IPC harness connector with a test lamp connected to a good ground. Does the test lamp illuminate? If yes, go to step 8 . If no, go to next step.
7. Repair the open in the MIL battery positive voltage circuit. After repairs, go to step 14 .
8. Inspect for poor connections at the harness connector of the IPC and repair as necessary. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
9. Inspect for poor connections at the harness connector of the PCM and repair as necessary. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 13 .
10. Repair the short to ground in the MIL battery positive voltage circuit. Replace the fuse. After repairs, go to step 14 .
11. Repair the short to voltage in the MIL control circuit. After repairs, go to step 14 .
12. Repair or replace the IPC. See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. After repairs, go to step 14 .
13. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
14. Operate the system in order to verify the repair. Did you correct the condition? If yes, system is okay. If no, go to step 2 .

If the problem is intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn OFF the ignition. Disconnect the PCM. See «COMPONENT LOCATIONS»(ref-132531-S12736680062002012100000) . Turn ON the ignition, with the engine OFF. Observe the MIL. Is the MIL illuminated? If yes, go to next step. If no, go to step 5 .
3. Remove the Instrument Panel Cluster (IPC). See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. Test the MIL control circuit for a short to ground between the PCM and the IPC. Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.
4. Repair or replace the IPC. See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT. After repairs, go to step 6 .
5. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
6. Operate the system in order to verify the repair. Did you correct the condition? If yes, system is okay. If no, go to step 2 .

DIAGNOSTIC TESTS

Note. Before clearing DTCs, perform powertrain diagnostic system check. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM. Record FREEZE FRAME and FAILURE RECORDS for reference during testing. Data will be erased when DTCs are cleared. If PCM is replaced, NEW PCM must be programmed using special manufacturer's equipment.

Conditions For Running DTC

The engine is running.

Conditions For Setting DTC

1. The PCM detects an electrical malfunction in the camshaft position actuator solenoid high control or low reference circuits.
2. The condition is present for more than 0.25 seconds.

Action Taken When DTC Sets

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. The control module records the operating conditions at the time the diagnostic fails.
2. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
3. The PCM disables the Cam phaser for the ignition cycle.

Conditions For Clearing MIL/DTC

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Start and idle the engine until normal operating temperature is achieved. With a scan tool, command the cam phaser solenoid to 100 percent. Does the engine run rough or stall? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Operate the vehicle within the Conditions for Running DTC or as close the Freeze Frame/Failure Records data that you observe. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S26930036242002012100000) .
4. Turn OFF the ignition. Disconnect the camshaft position actuator solenoid connector. Turn ON the ignition, with the engine OFF. With a Digital Multimeter (DMM), measure voltage between the camshaft position actuator solenoid high control circuit and a good ground. Does the DMM display voltage at battery voltage? If yes, go to next step. If no, go to step 7 .
5. Connect a test lamp between the camshaft position actuator solenoid high control circuit and ground. Does the test lamp illuminate? If yes, go to step 9 . If no, go to next step.
6. Connect a test lamp between the low reference circuit and battery positive. Does the test lamp illuminate? If yes, go to step 11 . If no, go to step 8 .
7. Test the camshaft position actuator solenoid high control circuit for an open or short to ground. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 10 .
8. Test the low reference circuit for an open. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 10 .
9. Test the camshaft position actuator solenoid high control circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
10. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
11. Inspect for poor connections at the harness connector of the camshaft position actuator solenoid. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 13 .
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to step 14 .
13. Replace the camshaft position actuator solenoid. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
14. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
15. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The scan tool camshaft phase control function increments the cam phaser in 10 percent increments. Each increment equates to 2.5 degrees of cam phasing. A cam phase angle of 15 degrees is achieved by commanding the camshaft actuation system with the scan tool to 60 percent.
2. Inspect any engine mechanical work that has been performed recently. Verify that the engine timing has not been altered.
3. If this DTC is set along with any crankshaft position (CKP) or camshaft position (CMP) sensor DTCs, then both the CKP and CMP sensor DTCs should be diagnosed prior to performing this diagnostic. The PCM uses both inputs to determine the actual camshaft position.
4. Check for the following items: A loose CMP sensor causing a variance in the sensor signal. A loose CKP sensor causing a variance in the sensor signal. Debris or contamination interfering with the camshaft position actuator solenoid valve assembly.
5. Engine oil has a major impact upon the camshaft actuation system's responsiveness. Oil temperature, pressure, viscosity, and quality can slow and/or inhibit the actuator systems ability to reach a desired phase angle.
6. An intermittent may be caused by any of the following conditions: A poor connection Rubbed through wire insulation A broken wire inside the insulation
7. Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Repair the circuits as necessary.

1. The engine is running.
2. The PCM has enabled the cam phaser.

1. The vehicle must be driven.
2. The difference between the desired CAM phase angle and the actual CAM phase angle is more than 1.5 degrees.
3. The CAM phaser is steady for 20 seconds.
4. The condition is present for 20 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.
3. The PCM disables the Cam phaser for the ignition cycle.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect a scan tool. Start and idle the engine for 2 minutes. Increase engine RPM to 1,500. With a scan tool, command the cam phase solenoid from 0 percent to 100 percent. Does the Cam Phase Angle Actual remain close to the Cam Phase Angle Desired at all commanded positions? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Operate the vehicle within the Conditions for Running DTC or as close the Freeze Frame/Failure Records data that you observe. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S05196700372002012100000) .
4. Let the engine idle. Does the engine run rough or stall? If yes, go to step 9 . If no, go to next step.
5. Turn OFF the ignition. Let the vehicle sit for 1 minute. Check the engine oil level. Is the engine oil level within operating range? If yes, go to next step. If no, add oil to bring oil level to correct operating range.
6. Install an oil pressure gage. Start the engine. Increase the engine RPM to 1,400 RPM. Observe the engine oil pressure. Does the oil pressure gage indicate engine oil pressure less than 28 psi? If yes, diagnose low oil pressure. See appropriate article in ENGINES. If no, go to next step.
7. Increase engine RPM to 1,500 RPM. With a scan tool, command the cam phase solenoid from 0 percent to 100 percent. Does the Cam Phase Angle Actual increment at all? If yes, go to next step. If no, go to step 10 .
8. Turn OFF the ignition. Disconnect the camshaft position actuator solenoid connector. With a Digital Multimeter (DMM), measure the resistance of the camshaft position actuator solenoid valve assembly. Does the resistance measure 8-12 ohms? If yes, go to step 13 . If no, go to step 19 .
9. Turn OFF the ignition. Disconnect the camshaft position actuator solenoid connector. Probe the camshaft position actuator solenoid high control circuit with a test lamp connected to good ground. Start the engine. With a scan tool, command the cam phase solenoid between 0 percent and 50 percent. Does the test lamp turn ON and OFF? If yes, go to next step. If no, go to step 15 .
10. Turn OFF the ignition. Remove the camshaft position solenoid valve assembly from the engine block. Inspect the camshaft position actuator solenoid valve assembly for the following: Torn screens. Debris on the screens. Debris clogging the oil ports. Missing screens. Oil seepage at the solenoid connector pins. Did you find a problem? If yes, go to step 19 . If no, go to next step.
11. Connect a jumper wire between battery ground and the camshaft position actuator low control at the solenoid. Connect a fused jumper wire between battery voltage and the camshaft position actuator high control at the solenoid. Momentarily touch the fused jumper to the battery voltage. Observe the spool valve inside the camshaft position actuator. Does the spool valve move from fully closed to fully opened? If yes, go to next step. If no, go to step 16 .
12. Inspect for the following conditions: Excessive timing chain play. Excessive camshaft end play. Excessive crankshaft end play. Proper installation of the camshaft position actuator assembly. See appropriate article in ENGINES. Repair as necessary. After repairs, go to step 21 .
13. Disconnect the PCM. With a DMM measure the resistance on the camshaft position actuator high control circuit. Does the resistance measure more than 5 ohms? If yes, go to step 18 . If no, go to next step.
14. Measure the resistance on the low reference circuit with a DMM. Does the resistance measure more than 5 ohms? If yes, go to step 18 . If no, see appropriate article in ENGINES.
15. Test the camshaft position actuator high control circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 17 .
16. Inspect for poor connections at the harness connector of the camshaft position actuator solenoid valve assembly. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
17. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 20 .
18. Repair the circuit. Did you repair the circuit? If yes, go to step 21 .
19. Replace the camshaft position actuator solenoid. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21 .
20. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
21. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
22. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The scan tool cam phase control function increments the cam phaser in 10 percent increments. Each increment equates to 2.5 degrees of cam phasing. A cam phase angle of 15 degrees is achieved by commanding the phaser with the scan tool to 60 percent.
2. Inspect any engine mechanical work that has been performed recently. Verify that the engine timing has not been altered.
3. If this DTC is set along with any crankshaft position (CKP) or camshaft position (CMP) sensor DTCs, then both the CKP and CMP sensor DTCs should be diagnosed prior to performing this diagnostic. The PCM uses both inputs to determine the actual camshaft position.
4. Check the following items: A loose CMP sensor causing a variance in the sensor signal. A loose CKP sensor causing a variance in the sensor signal. Excessive free play in the timing chain and gear assembly. Debris or contamination interfering with the camshaft position actuator solenoid valve assembly. Debris or contamination interfering with the camshaft position actuator assembly.
5. Engine oil has a major impact upon the camshaft actuation system's responsiveness. Oil temperature, viscosity, and quality can slow and/or inhibit the phaser's ability to reach a desired phase angle.
6. An intermittent may be caused by any of the following conditions: A poor connection. Rubbed through wire insulation. A broken wire inside the insulation. Repair the circuits as necessary.
7. Thoroughly check any circuitry that is suspected of causing the intermittent complaint.

1. DTC P0107, P0108, P0116, P0117, P0118, P0122, P0123, P0125, P0128, P0130, P0131, P0132, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0335, P0336, P0340, P0341, P0351, P0352, P0353, P0354, P0355, P0356, P0440, P0442, P0446, P0452, P0453, P0502, P0506, P0507, P0740, P0741, P0742, P1120, P1220, P1221, P1271, P1275, P1280, P1441, P1512, P1514, P1515, P1516, P1635, P1639, P1680, P1681, or P1860 are not set.
2. The engine run time is more than 40 seconds.
3. The change in engine speed is stable to within 50 RPM.
4. The engine speed is between 600-637 RPM.
5. The Torque Converter Clutch (TCC) is stable to within 2.5 percent.
6. All conditions stable for 1.5 seconds.

The actual MAP sensor signal is not within the predicted range for 14 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Inspect for the following conditions: MAP sensor seal missing or damaged. Restrictions in the MAP sensor vacuum source. Vacuum hoses disconnected, damaged, or incorrectly routed. Vacuum leaks between the intake manifold and the engine. Vacuum leaks at the throttle body. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
3. Install a scan tool. Turn ON the ignition, with the engine OFF. Monitor the scan tool and record the MAP sensor pressure. Compare the MAP sensor pressure to that of a known-good vehicle. Is the pressure difference between the vehicles less than 3 kPa? If yes, go to next step. If no, go to step 8 .
4. Observe the MAP sensor pressure on the scan tool. Start the engine. Does the MAP sensor value change? If yes, go to next step. If no, go to step 8 .
5. Turn OFF the ignition. Remove the MAP sensor from the vacuum source. Leave the electrical harness connected. Connect a hand vacuum pump to the MAP sensor. Turn ON the ignition, with the engine OFF. Observe the MAP sensor pressure as you SLOWLY apply vacuum 1 in. Hg at a time. Each inch of vacuum should result in a 3-4 kPa drop in the MAP sensor pressure. Increase the vacuum to 20 in. Hg. Does the scan tool indicate that the MAP sensor pressure decreases smoothly through the test? If yes, go to next step. If no, go to step 18 .
6. Observe the MAP sensor pressure with 20 in. Hg of vacuum applied to the MAP sensor. Does the scan tool indicate that the MAP sensor pressure is less than 34 kPa? If yes, go to next step. If no, go to step 8 .
7. Disconnect the MAP sensor from the hand vacuum pump. Does the MAP sensor pressure return to the original value that was observed in step 3 ? If yes, see «DIAGNOSTIC AIDS»(ref-132531-S15589481432002012100000) . If no, go to step 18 .
8. Turn OFF the ignition. Disconnect the MAP sensor electrical connector. Turn ON the ignition, with the engine OFF. Does the scan tool indicate that the MAP sensor voltage is more than 0.3 V? If yes, go to step 17 . If no, go to next step.
9. Probe the 5-volt reference circuit of the MAP sensor with a test lamp that is connected to a good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 16 .
10. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the MAP sensor and the signal circuit of the MAP sensor. Does the scan tool indicate that the MAP sensor voltage is near 5 V? If yes, go to next step. If no, go to step 15 .
11. Remove the jumper wire. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground. Does the voltage measure more than 5.2 V? If yes, go to step 13 . If no, go to next step.
12. Probe the low reference circuit of the MAP sensor with a test lamp that is connected to battery voltage. Does the test lamp illuminate? If yes, go to step 18 . If no, go to step 14 .
13. Test the 5-volt reference circuit of the MAP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 19 .
14. Test the low reference circuit of the MAP sensor for high resistance or an open. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 19 .
15. Test the signal circuit of the MAP sensor for high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 19 .
16. Test the 5-volt reference circuit of the MAP sensor for high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 19 .
17. Test the signal circuit of the MAP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 19 .
18. Inspect the MAP sensor for poor connections. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
19. Inspect the PCM for poor connections. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 21 .
20. Replace the MAP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 22 .
21. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
22. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
23. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Inspect for the following conditions: Restrictions in the MAP sensor vacuum source. MAP sensor seal is missing or damaged. Vacuum hoses disconnected, damaged, or incorrectly routed. Intake manifold vacuum leaks. Vacuum leaks at the throttle body.
2. This DTC may set due to any condition that may cause an unreasonably high or low MAP value including the following engine conditions: Incorrect cam timing. Restricted exhaust. Worn piston rings. Low fuel pressure.
3. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0122 or P0123 are not set.
2. The engine speed is less than 1000 RPM; or, the engine speed is more than 1000 RPM, the Throttle Position (TP) is more than 28 percent, and the pedal position is more than 1.2 percent.

The MAP sensor voltage is less than 0.2 volts for at least 6.25 seconds.

1. The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The PCM will store the conditions which were present when the DTC set as Freeze Frame/Failure Records data.
3. A history DTC is stored.
4. The PCM will substitute a default MAP value to control the fuel delivery. The scan tool will not show the defaulted value.
5. The engine will operate in Open Loop when the vehicle is traveling under 5 MPH.
6. The engine will operate in Closed Loop when the vehicle is traveling over 5 MPH.

1. The PCM will turn the Malfunction Indicator Lamp (MIL) OFF after three consecutive drive trips that the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Start the engine. Monitor the Diagnostic Trouble Code (DTC) Information using the scan tool. Does the scan tool indicate that DTC P1639 is current? If yes, see «DTC P1639: 5-VOLT REFERENCE B CIRCUIT»(ref-132531-S26177786862002012100000) . If no, go to next step.
3. With a scan tool, observe the MAP sensor voltage. Does the scan tool indicate that the voltage is less than 0.2 V? If yes, go to step 5 . If no, go to next step.
4. Observe 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 DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S36927787282002012100000) .
5. Turn OFF the ignition. Disconnect the MAP sensor electrical connector. Turn ON the ignition, with the engine OFF. Measure the voltage from the 5-volt reference circuit of the MAP sensor to a good ground. Does the voltage measure near 5 V? If yes, go to next step. If no, go to step 7 .
6. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the MAP sensor and the signal circuit of the MAP sensor. Does the scan tool indicate that the MAP sensor voltage is near 5 V? If yes, go to step 9 . If no, go to step 8 .
7. Test the 5-volt reference circuit of the MAP sensor for a short to ground or an open. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 10 .
8. Test the signal circuit of the MAP sensor for a short to ground or an open. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 10 .
9. Inspect for poor connections at the MAP sensor. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
10. Inspect for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 12 .
11. Replace the MAP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The 5-volt reference circuits used by the various engine control components are internally connected in the PCM. If a component's 5-volt reference circuit is shorted to ground, the other 5-volt reference circuits may be affected.
2. Inspect the MAP sensor vacuum source for leaks, restrictions, or poor connections.
3. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0122 or P0123 are not set.
2. The Throttle Position (TP) is less than 15 percent.
3. The vehicle speed is less than 1 MPH.
4. The engine run time is more than 20-40 seconds.

The MAP sensor voltage is more than 4.2 volts for at least 1 second.

1. The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The PCM will store the conditions which were present when the DTC set as Freeze Frame/Failure Records data.
3. A history DTC is stored.
4. The PCM will substitute a defaulted MAP value to control the fuel delivery. The scan tool will not show the defaulted value.
5. The engine will operate in Open Loop when the vehicle is traveling under 5 MPH.
6. The engine will operate in Closed Loop when the vehicle is traveling over 5 MPH.

1. The PCM will turn the Malfunction Indicator Lamp (MIL) OFF after three consecutive drive trips that the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect a scan tool. Start the engine. Let the engine idle. Does the scan tool indicate that the MAP sensor voltage is greater than 4.2 V? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC, or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S26517610112002012100000) .
4. Turn OFF the ignition. Disconnect the MAP sensor electrical connector. Turn ON the ignition, with engine OFF. Does the scan tool indicate that the MAP sensor voltage is less than 0.2 V? If yes, go to next step. If no, go to step 7 .
5. Measure the voltage from the 5-volt reference circuit to the low reference circuit at the MAP sensor electrical connector. Does the voltage measure 4.7-5.2 V? If yes, go to step 10 . If no, go to next step.
6. Does the voltage measure more than 5.2 V? If yes, go to step 9 . If no, go to step 8 .
7. Test the signal circuit of the MAP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 11 .
8. Test the low reference circuit of the MAP sensor for an open. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 11 .
9. Test the 5-volt reference circuit of the MAP sensor for a short to voltage. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 11 .
10. Inspect for poor connections at the MAP sensor. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
11. Inspect for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 13 .
12. Replace the MAP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 14 .
13. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
14. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
15. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The 5-volt reference circuits used by the various engine control components are internally connected in the PCM. If a component's 5-volt reference circuit is shorted to voltage, the other 5-volt reference circuits may be affected.
2. Inspect the MAP sensor vacuum source for leaks, restrictions, or poor connections.
3. This DTC may set as the result of a misfire.
4. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0116, P0117, P0118, P0125, P0128, P0502, or P0503 are not set.
2. The engine run time is more than 320 seconds.
3. The vehicle speed sensor indicates that vehicle speed is more than 15 MPH.

The IAT is more than 262°F (128°C) for 3 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Is the IAT sensor temperature more than 262°F (128°C)? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC reset? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S11786937842002012100000) .
4. Turn OFF the Ignition. Disconnect the IAT sensor. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Is the IAT sensor temperature less than -38°F (-39°C)? If yes, go to step 6 . If no, go to next step.
5. Test the signal circuit of the IAT sensor for a short to ground or a short to IAT low reference circuit and repair as necessary. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 7 .
6. Replace the IAT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 9 .
7. Turn OFF the ignition. Disconnect the PCM. Inspect for poor connection at the PCM harness connector. Did you find and correct the condition? If yes, go to step 9 . If no, go to next step.
8. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
9. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
10. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. When the vehicle is at ambient temperature the IAT sensor and ECT sensor temperatures should be relatively close to each other. See appropriate SENSOR OPERATING RANGE CHARTS article.
2. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0116, P0117, P0118, P0125, P0128, P0502, or P0503 are not set.
2. The engine run time is more than 320 seconds.
3. The vehicle speed sensor indicates that vehicle speed is less than 15 MPH.

The IAT sensor signal voltage indicates that the intake air temperature is less than -38°F (-39°C) for more than 3 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Is the IAT sensor temperature less than -36°F (-38°C)? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC reset? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S14692058072002012100000) .
4. Turn OFF the ignition. Disconnect the IAT sensor. Connect a Digital Multimeter (DMM) between the signal circuit and the low reference circuit of the IAT sensor harness. Turn ON the ignition. Does the DMM voltage measure more than 5 V? If yes, go to next step. If no, go to step 6 .
5. Test the signal circuit for a short to voltage. Repair as necessary. Did you find and correct the condition? If yes, go to step 14 . If no, see «DIAGNOSTIC AIDS»(ref-132531-S14692058072002012100000) .
6. Turn OFF the ignition. Disconnect the IAT sensor. Connect a 3-amp fused jumper wire between the signal circuit of the IAT sensor and the low reference circuit at the IAT sensor. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Is the IAT sensor temperature more than 262°F (128°C)? If yes, go to step 10 . If no, go to next step.
7. Turn OFF the ignition. Connect a 3-amp fused jumper wire between the signal circuit of the IAT sensor and a known-good ground. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Is the IAT sensor temperature more than 262°F (128°C)? If yes, go to step 9 . If no, go to next step.
8. Test the signal circuit of the IAT sensor for an open circuit or high resistance. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 11 .
9. Test the IAT sensor low reference circuit for high resistance or an open. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 11 .
10. Inspect for poor connections at the harness connector of the IAT sensor. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
11. Inspect for poor connections at the harness connector of the PCM. Repair the connections as necessary. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 13 .
12. Replace the IAT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 14 .
13. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
14. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
15. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. When the vehicle is at ambient temperature the IAT sensor and ECT sensor temperatures should be relatively close to each other. See appropriate SENSOR OPERATING RANGE CHARTS article.
2. If a short to a separate 5-volt source occurs this DTC may set. If this condition exists, a continuity test to all other PCM 5-volt reference circuits will be necessary.
3. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The ignition is ON.
2. DTCs P0112, P0113, P0117, P0118, P0125, P0128, P0601, P0602, P0604, P0606, P1481, P1482, P1484, P1621, or P1683 are not set.
3. The vehicle has a minimum soak time of 8 hours.
4. The Intake Air Temperature (IAT) is more than 59°F (15°C).

The temperature difference between the ECT and the IAT at start up is more than 59°F (15°C).

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Is the cooling system low on coolant? If yes, repair and refill cooling system. If no, go to next step.
3. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit and the low reference circuit of the ECT sensor. Turn ON the ignition, with the engine OFF. Observe the ECT sensor temperature with a scan tool. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to next step. If no, go to step 5 .
4. Turn OFF the ignition. Disconnect the IAT sensor. Connect a 3-amp fused jumper wire between the signal circuit and the low reference circuit of the IAT sensor. Turn ON the ignition, with the engine OFF. Observe the IAT sensor temperature with a scan tool. Does the scan tool indicate that the IAT sensor temperature is more than 280°F (138°C)? If yes, go to step 8 . If no, see «DIAGNOSTIC AIDS»(ref-132531-S01806187852002012300000) .
5. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and a known-good ground. Turn ON the ignition, with the engine OFF. Observe the ECT sensor temperature with a scan tool. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to next step. If no, go to step 7 .
6. Test the ECT sensor low reference circuit for a high resistance or an open. Repair the circuit as necessary. Repair as necessary. After repairs, go to step 11 .
7. Test the ECT sensor signal circuit for a high resistance or an open. Repair the circuit as necessary. After repairs, go to step 11 .
8. Remove the ECT sensor. Suspend the ECT sensor and a thermometer in a pan of water. Place the pan on a burner or hot plate. Test the resistance of the ECT sensor through 50-194°F (10-90°C). See appropriate SENSOR OPERATING RANGE CHARTS article. Does the resistance and temperature closely match the Temperature vs Resistance table? If yes, go to next step. If no, go to step 10 .
9. Reinstall the ECT sensor. When complete, see «DIAGNOSTIC AIDS»(ref-132531-S01806187852002012300000) .
10. Replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
11. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
12. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTC P0116 is designed to detect an ECT sensor that is skewed high.
2. An IAT sensor that is skewed could cause this DTC to set.
3. When checking the ECT sensor, the Temperature vs Resistance table should be used in order to determine if a skewed sensor is the problem. See appropriate SENSOR OPERATING RANGE CHARTS article.
4. If the engine has been allowed to sit overnight, the ECT and IAT temperature should be within the calculated amount.

The engine has been running more than 128 seconds.

The ECT sensor indicates an engine coolant temperature that is more than 280°F (138°C) for longer than 6.25 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) if a failure is detected during 2 consecutive key cycles.
2. The control module sets the DTC and records the operating conditions at the time the diagnostic failed. The failure information is stored in the scan tool Freeze Frame/Failure Records.

Conditions For Clearing MIL or DTC

1. The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed.
2. A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 40°F (22°C) from the start-up coolant temperature and the engine coolant reaches a temperature that is more than 158°F (70°C) during the same ignition cycle.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect a scan tool. Turn ON the ignition, with the engine OFF. Observe the ECT sensor temperature display. Does the scan tool indicate that the ECT sensor temperature is greater than 280°F (138°C)? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC reset? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S41646164212002012100000) .
4. Disconnect the ECT sensor. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate that the ECT sensor temperature is less than -36°F (-38°C)? If yes, go to step 6 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the PCM. Test the signal circuit of the ECT sensor for a short to ground or a short to any low reference circuit. Did you find and correct the condition? If yes, go to step 8 . If no, go to step 7 .
6. Replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 8 .
7. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. An overheating condition may cause this DTC to set.
2. After starting the engine, the ECT sensor temperature should rise steadily to about 194°F (90°C) then stabilize after the thermostat opens.
3. Use the Temperature vs. Resistance Value Table in order to test the ECT sensor at various temperature levels in order to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns. See appropriate SENSOR OPERATING RANGE CHARTS article.
4. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

The engine has been running more than 60 seconds.

The ECT sensor temperature is less than 122°F (50°C) for more than 6.25 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) if a failure is detected during 2 consecutive key cycles.
2. The control module sets the DTC and records the operating conditions at the time the diagnostic failed. The failure information is stored in the scan tool Freeze Frame/Failure Records.

1. The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed.
2. A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 40°F (22°C) from the start-up coolant temperature and the engine coolant reaches a temperature that is more than 158°F (70°C) during the same ignition cycle.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate that the ECT sensor temperature is less than -36°F (-38°C)? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC reset? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S12540139472002012100000) .
4. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and the low reference circuit at the ECT sensor. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate ECT sensor temperature greater than 280°F (138°C)? If yes, go to step 8 . If no, go to next step.
5. Turn OFF the ignition. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and a known-good ground. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate that the ECT sensor temperature is greater than 280°F (138°C)? If yes, go to step 7 . If no, go to next step.
6. Test the signal circuit of the ECT sensor for the following conditions: A short to voltage. A high resistance. An open circuit. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 12 . If no, go to next step.
7. Test the ECT sensor reference low circuit for a high resistance or an open. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 9 .
8. Inspect for poor connections at the harness connector of the ECT sensor. Repair the connections as necessary. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 10 .
9. Inspect for poor connections at the harness connector of the PCM. Repair the connections as necessary. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 11 .
10. Replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 12 .
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. If a short to a separate 5-volt source occurs, this DTC may set. If this is the problem, a continuity test to all other PCM circuits will be necessary to diagnose the specific circuit.
2. After starting the engine, the ECT should rise steadily to about 194°F (90°C) then stabilize after the thermostat opens.
3. Use the Temperature vs. Resistance Table in order to test the ECT sensor at various temperature levels in order to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns. See appropriate SENSOR OPERATING RANGE CHARTS article.
4. If an intermittent condition exists, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The ignition switch is in the crank or run position.
2. DTC P1635 is not set.
3. The ignition voltage is more than 5.23 volts.

The TP sensor 1 and 2 voltages are not within a calibrated range.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the first trip in which the diagnostic runs and fails.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P1120 and P1220 set? If yes, see «DTC P1120: TP SENSOR CIRCUIT»(ref-132531-S41757864772002012100000) and «DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE»(ref-132531-S22027517412002012900000) .

The DTC indicates 2 separate faults, one fault with TP sensor 1 and one fault with TP sensor 2. The DTC P1120 diagnostic table along with the DTC P1220 diagnostic table may need to be followed to find both faults. See DTC P1120: TP SENSOR CIRCUIT and DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE .

1. The ignition switch is in the crank or run position.
2. DTC P1635 is not set.
3. The ignition voltage is more than 5.23 volts.

The TP sensor 1 and 2 voltages are not within a calibrated range.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the first trip in which the diagnostic runs and fails.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P1120 and P1220 set? If yes, see «DTC P1120: TP SENSOR CIRCUIT»(ref-132531-S41757864772002012100000) and «DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE»(ref-132531-S22027517412002012900000) .

The DTC indicates 2 separate faults, one fault with TP sensor 1 and one fault with TP sensor 2. The DTC P1120 diagnostic table along with the DTC P1220 diagnostic table may need to be followed to find both faults. See DTC P1120: TP SENSOR CIRCUIT and DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE .

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0130, P0131, P0132, P0133, P0134, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0325, P0335, P0336, P0420, P0440, P0442, P0446, P0452, P0453, P0480, P0502 and P0503 (A/T only), P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1281, P1441, P1481, P1482, P1484, P1512, P1514, P1515, P1621, P1635, and P1639 are not set.
2. The engine has run more than 30 seconds and for less than 20 minutes.
3. The minimum Intake Air Temperature (IAT) is more than 19°F (-7°C).
4. The engine coolant temperature at start up is less than 104°F (40°C).

1. The average air flow is more than 20 g/s.
2. The vehicle has traveled more than 0.5 miles over 25 MPH.
3. Enough air flow has entered the engine and the engine coolant temperature has not risen to 104°F (40°C) for 60 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Is the cooling system low on coolant? If yes, locate and repair source of coolant loss and refill system. If no, go to next step.
3. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit and the low reference circuit of the ECT sensor. Turn ON the ignition, with the engine OFF. Observe the ECT sensor temperature with a scan tool. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to step 7 . If no, go to next step.
4. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and a known-good ground. Turn ON the ignition, with the engine OFF. Observe the ECT sensor temperature with a scan tool. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to next step. If no, go to step 6 .
5. Test the ECT sensor low reference circuit for a high resistance or an open. Repair the circuit as necessary. After repairs, go to step 10 .
6. Test the ECT sensor signal circuit for a high resistance or an open. Repair the circuit as necessary. After repairs, go to step 10 .
7. Remove the ECT sensor. Suspend the ECT sensor and a thermometer in a pan of water. Place the pan on a burner or hot plate. Test the resistance of the ECT sensor through 50-194°F (10-90°C). See appropriate SENSOR OPERATING RANGE CHARTS article. Does the resistance and temperature closely match the Temperature vs Resistance Table? If yes, go to next step. If no, go to step 9 .
8. Install the ECT sensor. When complete, diagnose thermostat.
9. Replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
10. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
11. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTC P0125 is designed to detect a skewed ECT sensor or a faulty thermostat.
2. A skewed IAT sensor may cause this DTC to set. The IAT sensor should read near ambient temperature.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0122, P0123, P0125, P0130, P0131, P0132, P0171, P0172, P0201, P0202, P0203, P0204, P0300, P0301, P0302, P0303, P0304, P0325, P0336, P0420, P0440, P0442, P0446, P0452, P0453, P0480, P0502, P0503 (A/T only), and P1441 are not set.
2. The engine has run more than 30 seconds and less than 20 minutes.
3. The minimum Intake Air Temperature (IAT) is more than 19°F (-7°C).
4. The engine coolant temperature at start up is less than 149°F (65°C).

1. The average air flow is more than 20 g/s.
2. The vehicle has traveled more than 1.5 miles over 25 MPH.
3. Enough air flow has entered the engine and the engine coolant temperature has not risen to 176°F (80°C) for 30 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) if a failure is detected during 2 consecutive key cycles.
2. The control module sets the DTC and records the operating conditions at the time the diagnostic failed. The failure information is stored in the scan tool Freeze Frame/Failure Records.

1. The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed.
2. A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 40°F (22°C) from the start-up coolant temperature and the engine coolant reaches a temperature that is more than 158°F (70°C) during the same ignition cycle.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Is the cooling system low on coolant? If yes, locate and repair source of coolant loss and refill system. If no, go to next step.
3. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit and the low reference circuit of the ECT sensor. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to step 7 . If no, go to next step.
4. Turn OFF the ignition. Disconnect the ECT sensor. Connect a 3-amp fused jumper wire between the signal circuit of the ECT sensor and a known-good ground. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ECT sensor temperature. Does the scan tool indicate that the ECT sensor temperature is more than 280°F (138°C)? If yes, go to next step. If no, go to step 6 .
5. Test the ECT sensor low reference circuit for a high resistance or an open. Repair the circuit as necessary. After repairs, go to step 10 .
6. Test the ECT sensor signal circuit for a high resistance or for an open. Repair the circuit as necessary. After repairs, go to step 10 .
7. Remove the ECT sensor. Suspend the ECT sensor and a thermometer in a pan of water. Place the pan on a burner or hot plate. Test the resistance of the ECT sensor through 50-194°F (10-90°C). See appropriate SENSOR OPERATING RANGE CHARTS article. Does the resistance and temperature closely match the Temperature vs Resistance Table? If yes, go to next step. If no, go to step 9 .
8. Install the ECT sensor. Diagnose and repair engine not reaching normal operating temperature.
9. Replace the ECT sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
10. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
11. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. A DTC P0128 is designed to detect a faulty thermostat.
2. A skewed IAT sensor may cause this DTC to set.

1. DTCs P0105, P0107, P0108, P0116, P0117, P0118, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0201, P0202, P0203, P0204, P0205, P0206, P0300-P0306, P0335, P0336, P0351-P0356, P0601, P0602, P0604, P0606, P1120, P1133, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1635, P1639, or P1681 are not set.
2. The engine run time is more than 100 seconds.
3. The engine speed is between 1200-3400 RPM.
4. The TP indicated angle is between 15-50 percent.
5. The ECT sensor is more than 176°F (80°C).
6. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
7. The above conditions have been met for 5 seconds.

Conditions For Setting The DTC

The engine is in Open Loop for 7.5 seconds out of 12.5 seconds.

Action Taken When the DTC Sets

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

Conditions For Clearing the MIL/DTC

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. The engine has reached operating temperature. Operate the engine above 1200 RPM for two minutes. With a scan tool, observe the HO2S voltage parameter. Does scan tool indicate HO2S voltage varying outside 400-500 mV? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Inspect and test for the following conditions: Exhaust leak. The HO2S is installed correctly. Damaged wiring. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the HO2S 1 connector. Turn ON the ignition. Measure the voltage on the HO2S high signal circuit. Does the voltage measure near 450 mV? If yes, go to next step. If no, go to step 8 .
6. Jumper the HO2S high signal circuit to the low signal circuit (PCM side). With a scan tool, observe HO2S 1 voltage parameter. Does the scan tool indicate HO2S 1 voltage at or near 0 mV? If yes, go to step 9 . If no, go to next step.
7. Test the low signal circuit for an open high resistance or a short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
8. Test the high signal circuit for an open high resistance or a short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
9. Test for poor connections at the HO2S. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
10. Inspect and test for the following conditions: Fuel contamination. Engine oil or coolant consumption. Use of improper RTV sealant. Replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
11. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680 or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The engine run time is more than 10 seconds.
5. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
6. The Engine Coolant Temperature (ECT) sensor is more than 158°F (70°C).
7. The loop status is closed.
8. The Throttle Position (TP) indicated angle is between 15-50 percent.
9. The manifold absolute pressure (MAP) sensor is more than 25 kPa.
10. The above conditions have been met for 3.8 seconds.

The HO2S 1 signal voltage is less than 52 mV for 125 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running parameters. With a scan tool, observe the HO2S voltage parameter. Does the voltage remain below 52 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S connector. Turn ON the ignition. Does the scan tool indicate HO2S 1 voltage is less than 400 mV? If yes, go to next step. If no, go to step 7 .
5. Test the HO2S high signal circuit for a short to ground or a short to the HO2S low signal circuit. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
6. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to step 8 .
7. Inspect the vehicle for any of the conditions in «DIAGNOSTIC AIDS»(ref-132531-S31706829442002012100000) . If no problem is found, replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Fuel pressure. System will be lean if pressure is too low. It may be necessary to monitor fuel pressure while driving the vehicle at various road speeds and/or loads to confirm. See appropriate BASIC DIAGNOSTIC PROCEDURES article.
2. MAP sensor. An output that causes the PCM to sense a lower than normal manifold pressure, or high vacuum, can cause the system to go lean. Disconnecting the MAP sensor will allow the PCM to substitute a fixed, or default, value for the MAP sensor. If the lean condition is gone when the MAP sensor is disconnected, refer to DTC P0105 for further diagnosis. See «DTC P0105: MAP SYSTEM PERFORMANCE»(ref-132531-S33534962272002012100000) .
3. Fuel contamination. Water, in even small amounts, near the in-tank fuel pump inlet, can be delivered to the injector. The water causes a lean exhaust and can set a DTC P0131.
4. Sensor harness. The HO2S 1 sensor pigtail may be mis-positioned and contacting the exhaust manifold.
5. Engine misfire. A misfiring cylinder will result in unburned oxygen in the exhaust, which could cause a DTC P0131. See «DTC P0300: ENGINE MISFIRE DETECTED»(ref-132531-S11924089322002012100000) .
6. Cracked Heated Oxygen Sensor 1 (HO2S 1). A cracked HO2S 1 sensor could cause a DTC P0131.
7. Plugged fuel filter. A plugged fuel filter can cause a lean condition and cause a DTC P0131 to set.
8. Plugged oxygen sensor (HO2S 1). A plugged reference port on the HO2S 1 will indicate a lower then normal voltage output from the HO2S 1 sensor.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The engine run time is more than 10 seconds.
5. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
6. The engine is operating in Closed Loop.
7. The Throttle Position (TP) indicated angle is between 15-50 percent.
8. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
9. The manifold absolute pressure (MAP) sensor is more than 25 kPa.
10. The above conditions have been met for 3.8 seconds.

The HO2S 1 voltage is more than 946 mV for 50 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.
4. The vehicle will operate in Open Loop operation.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running this DTC. With a scan tool, observe the HO2S voltage parameter. Does the voltage measure above 946 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S connector for the sensor that applies to this DTC. Turn ON the ignition, with the engine OFF. Use the scan tool in order to monitor the HO2S voltage for the sensor that applies to this DTC. Is the HO2S voltage near 447 mV? If yes, go to next step. If no, go to step 6 .
5. The HO2S is detecting a rich exhaust condition or may be contaminated. Check for one of the following conditions: HO2S connector water intrusion. Silicone contaminated HO2S. Fuel-contaminated engine oil. Incorrect fuel pressure. A leaking fuel pressure regulator. Rich fuel injectors. Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 7 .
6. Test the HO2S high signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 8 .
7. Replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 9 .
8. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
9. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
10. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The DTC P0132 or rich exhaust is most likely caused by one of the following items

1. Fuel pressure. The system will go rich if fuel pressure is too high. The PCM can compensate for some increase, however, if it gets too high, a DTC P0132 will be set.
2. Leaking injector. A leaking or malfunctioning injector can cause the system to go rich causing a DTC P0132.
3. MAP sensor. An output that causes the PCM to sense a higher than normal manifold pressure, or a low vacuum, can cause the system to go rich. Disconnecting the MAP sensor electrical connector will allow the PCM to set a fixed value for the MAP sensor. Substitute a different MAP sensor if the rich condition is gone while the MAP sensor is disconnected.
4. Pressure regulator. Check for a leaking fuel pressure regulator diaphragm by checking for the presence of liquid fuel in the vacuum line to the fuel pressure regulator.
5. TP sensor. An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine accelerating.
6. HO2S 1 contamination. Inspect the HO2S 1 sensor for Silicone contamination from fuel or the use of improper RTV sealant. The HO2S 1 sensor may have a white powdery coating and this will result in a high but false voltage signal, indicating a rich exhaust. The PCM will then reduce the amount of fuel delivered to the engine causing a severe surge or driveability problem.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The Engine Coolant Temperature (ECT) sensor is more than 158°F (70°C).
4. The engine speed is between 1450-1900 RPM.
5. The loop status is closed.
6. The Throttle Position (TP) indicated angle is between 25-30 percent.
7. The Evaporative (EVAP) emission purge solenoid command is more than 10 percent.
8. The above conditions have been met for 30 seconds.

The average HO2S 1 response times are more than 850 mS for rich to lean sweeps or 950 mS for lean to rich sweeps or the sum of rich to lean and lean to rich sweeps is more than 2100 mS.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. The engine has reached operating temperature. Operate the engine above 1200 RPM for two minutes. With a scan tool, observe the HO2S voltage parameter. Does scan tool indicate HO2S voltage varying outside 400-500 mV? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Inspect and test for the following conditions: Exhaust leak. The HO2S is installed correctly. Damaged wiring. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition. Measure the voltage on the HO2S high signal circuit (PCM side). Does the voltage measure near 450 mV? If yes, go to next step. If no, go to step 8 .
6. Jumper the HO2S high signal circuit to the HO2S low signal circuit (PCM side). With a scan tool, observe HO2S voltage parameter. Does the scan tool indicate HO2S voltage at or near 0 mV? If yes, go to step 9 . If no, go to next step.
7. Test the HO2S low signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
8. Test the HO2S high signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
9. Test for poor connections at the HO2S. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
10. Inspect and test for the following conditions: Fuel contamination. Engine oil or coolant consumption. Use of improper RTV sealant. Replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
11. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is more than 176°F (80°C).
5. The Throttle Position (TP) indicated angle is between 15-50 percent for 20 seconds.
6. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
7. The manifold absolute pressure (MAP) sensor is more than 25 kPa.
8. The engine run time is more than 30 seconds.
9. The Mass Air Flow (MAF) is more than 7 g/s.

The HO2S 1 voltage is between 399-499 mV for 125 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame and Failure Records buffers.
3. A history DTC stores.
4. The vehicle will operate in Open Loop operation.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. The engine has reached operating temperature. Operate the engine above 1200 RPM for two minutes. With a scan tool, observe the HO2S voltage parameter. Does scan tool indicate HO2S voltage varying outside 400-500 mV? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Inspect and test for the following conditions: Exhaust leak. The HO2S is installed correctly. Damaged wiring. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition. Measure the voltage on the HO2S high signal circuit (PCM side). Does the voltage measure near 450 mV? If yes, go to next step. If no, go to step 8 .
6. Jumper the HO2S high signal circuit to the HO2S low signal circuit (PCM side). With a scan tool, observe the HO2S voltage parameter. Does the scan tool indicate HO2S voltage at or near 0 mV? If yes, go to step 9 . If no, go to next step.
7. Test the HO2S low signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
8. Test the HO2S high signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
9. Test for poor connections at the HO2S. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
10. Inspect and test for the following conditions: Fuel contamination. Engine oil or coolant consumption. Use of improper RTV sealant. Replace the affected HO2S sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
11. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The ignition 1 signal is between 10-16.5 volts.
3. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
4. The air flow calculated is less than 60 g/s.
5. The fuel level sensor is more than 10 percent.
6. The engine run time is more than 60 seconds.

The HO2S heater current is not within the calibrated range for more than 200 seconds.

1. The PCM illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.

1. The PCM turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF, and immediately record the HO2S signal voltage. Monitor the HO2S signal voltage for 2 minutes. Does the HO2S signal voltage go from bias voltage to more than or less than 300-600 mV? If yes, go to step 8 . If no, go to next step.
3. Using the scan tool, command the HO2S heater ON. Monitor the HO2S signal voltage for 2 minutes. Does the HO2S signal voltage go from bias voltage to more than or less than 300-600 mV? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
4. Turn OFF the ignition. Disconnect the HO2S connector. Turn ON the ignition, with the engine OFF. Probe the HO2S ignition 1 voltage circuit with a test lamp that is connected to a good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 11 .
5. Connect a test lamp between the HO2S heater low control circuit and the HO2S ignition 1 voltage circuit. With a scan tool, command the HO2S heater ON and OFF. Does the test lamp turn ON and OFF with each command? If yes, go to step 9 . If no, go to next step.
6. Does the test lamp remain illuminated with each command? If yes, go to step 8 . If no, go to next step.
7. Test the HO2S heater low control circuit for a short to voltage or an open. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 10 .
8. Test the HO2S heater low control circuit for a short to ground. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 10 .
9. Inspect for poor connections at the HO2S connector. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 12 .
10. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 14 . If no, go to step 13 .
11. Repair the HO2S ignition 1 voltage circuit. After repairs, go to step 14 .
12. Replace the appropriate HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 14 .
13. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
14. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
15. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
5. The loop status is closed.
6. The Throttle Position (TP) indicated angle is between 15-50 percent for 3.8 seconds.
7. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
8. The above conditions have been met for 3.8 seconds.

The HO2S 2 remains below 43 mV for 150 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running this DTC. With a scan tool, observe the HO2S voltage parameter. Does the voltage remain below 43 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition. Does the scan tool indicate the HO2S 2 voltage is less than 400 mV? If yes, go to next step. If no, go to step 7 .
5. Test the HO2S high signal circuit for a short to ground or a short to the HO2S low signal circuit. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
6. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to step 8 .
7. Replace the HO2S 2 sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
5. The Throttle Position (TP) indicated angle is between 15-50 percent for 3.8 seconds.
6. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
7. The manifold absolute pressure (MAP) is more than 25 kPa.
8. The above conditions have been met for 3.8 seconds.

The HO2S 2 voltage is more than 1042 mV for 50 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running this DTC. With a scan tool, observe the HO2S voltage parameter. Is the HO2S voltage more than 1042 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S electrical connector. Turn ON the ignition, with the engine OFF. Using the scan tool, observe the HO2S voltage. Is the HO2S voltage near 447 mV? If yes, go to next step. If no, go to step 6 .
5. The HO2S is detecting a rich exhaust condition or may be contaminated. Check for one of the following conditions: HO2S connector water intrusion. Silicone contaminated HO2S. Fuel contaminated engine oil. Incorrect fuel pressure. A leaking fuel pressure regulator. Rich fuel injectors. Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 7 .
6. Test the HO2S high signal for a short to voltage. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 8 .
7. Replace the HO2S 2. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 9 .
8. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
9. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
10. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Check for the following conditions

1. A rich exhaust. An overly rich exhaust may load the catalyst causing high HO2S 2 signal voltages.
2. Silicone contamination. Silicone contamination of HO2S 2 could cause a false rich condition. A powdery white deposit on the sensor will indicate this condition.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is more than 104°F (40°C).
5. The loop status is closed.
6. The Throttle Position (TP) indicated angle is between 15-50 percent.
7. The Mass Air Flow (MAF) sensor is more than 10 g/s.
8. The Accelerator Pedal Position (APP) indicated angle is more than 1.2 percent.
9. The manifold absolute pressure (MAP) is more than 25 kPa.
10. The above conditions have been met for 140 seconds.

The HO2S 2 remains between 425 mV and 475 mV for 125 seconds.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. The engine has reached operating temperature. Operate the engine above 1200 RPM for two minutes. With a scan tool, observe the HO2S voltage parameter. Does scan tool indicate HO2S voltage varying outside 425-475 mV? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Inspect and test for the following conditions: Exhaust leak. The HO2S is installed correctly. Damaged wiring. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition. Measure the voltage on the HO2S high signal circuit (PCM side). Does the voltage measure near 450 mV? If yes, go to next step. If no, go to step 8 .
6. Jumper the HO2S high signal circuit to the HO2S low signal circuit (PCM side). With a scan tool, observe HO2S voltage parameter. Does the scan tool indicate HO2S voltage at or near 0 mV? If yes, go to step 9 . If no, go to next step.
7. Test the HO2S low signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
8. Test the HO2S high signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
9. Test for poor connections at the HO2S. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
10. Inspect and test for the following conditions: Fuel contamination. Engine oil or coolant consumption. Use of improper RTV sealant. Replace the affected HO2S sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
11. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0201, P0202, P0203, P0204, P0300, P0325, P0341, P0446, P0502, P0503, P0506, P0507, P0601, P0602, P1133, or P1441 are not set.
2. The Engine Coolant Temperature (ECT) is between 140-239°F (60-115°C).
3. The intake air temperature is between -13-239°F (-25-115°C).
4. The manifold absolute pressure (MAP) is above 26 kPa.
5. The vehicle speed is less than 82 MPH.
6. The engine speed is between 550-3400 RPM.
7. The barometric pressure is more than 72 kPa.
8. The fuel ethanol composition is less than 88 percent.
9. The fuel level is more than 9.8 percent.

The Fuel Trim Index is above 23 percent.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect the scan tool. Start the engine and drive the vehicle under normal conditions until the engine reaches operating temperature and is in closed loop. Turn OFF the engine. Turn ON the ignition, with the engine OFF. Review the Freeze Frame Records/Failure Records and record displayed data for this DTC. Does the scan tool indicate that the Fuel Trim Index is greater than 23%? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S04279036282002012100000) .
3. Operate the engine at idle. Using the scan tool, observe the O2S parameters. Does the scan tool indicate that the values are 200-800 mv and fluctuating? If yes, go to next step. If no, go to step 5 .
4. Turn OFF the engine. Inspect the following items: Vacuum hoses for splits, kinks, and proper connections. If fuel pressure is too low, this DTC may set. Fuel contamination. Did you find and correct the condition? If yes, go to step 7 . If no, go to step 6 .
5. Turn OFF the engine. Check the O2S for proper installation. Check to ensure electrical connectors and wires are secured and not contacting the exhaust system. Check for short between the signal circuit and low reference circuit. Did you find and correct the condition? If yes, go to step 7 . If no, diagnose fuel system. See appropriate BASIC DIAGNOSTIC PROCEDURES article.
6. Operate the engine at idle. Check for missing, loose, or leaking exhaust components. Check for vacuum leaks at the intake manifold, throttle body, and injector O-rings. Check the air induction system and air intake ducts for leaks. Check crankcase ventilation system for leaks. Did you find and correct the condition? If yes, go to next step. If no, see appropriate article in ENGINES.
7. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
8. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The system will go lean if an injector is not supplying enough fuel.
2. A lean condition could be present during high fuel demand due to a fuel pump that does not pump enough fuel.
3. Using a scan tool, review the Failure Records. If an intermittent condition is suspected, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0131, P0132, P0133, P0134, P0201, P0202, P0203, P0204, P0300, P0325, P0341, P0446, P0502, P0503, P0506, P0507, P0601, P0602, P1133, or P1441 are not set.
2. The Engine Coolant Temperature (ECT) is between 140-239°F (60-115°C).
3. The intake air temperature is between -13-239°F (-25-115°C).
4. The manifold absolute pressure (MAP) is above 26 kPa.
5. The vehicle speed is less than 82 MPH.
6. The engine speed is between 550-3400 RPM.
7. The Barometric (BARO) pressure is more than 72 kPa.
8. The fuel ethanol composition is less than 88 percent.
9. The fuel level is more than 9.8 percent.

1. The fuel trim index is below -42 percent.
2. Diagnostics have determined that a rich condition was not due to excessive vapor.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Review the Freeze Frame/Failure Records and record displayed data for this DTC. Select Fuel Trim Data parameter. Start the engine and observe the Fuel Trim Index. Does the scan tool indicate that the Fuel Trim Index is less than -42%? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S42293360772002012100000) .
3. Operate the engine at idle. Observe O2S parameters with a scan tool. Does the scan tool indicate that the values are 200-800 mV and fluctuating? If yes, go to next step. If no, go to step 5 .
4. Turn OFF the engine. Inspect the following items: Vacuum hoses for splits, kinks, and proper connections. The air intake duct for being collapsed or restricted. The air filter for being dirty or restricted. For objects blocking throttle body. Did you find and correct the condition? If yes, go to step 7 . If no, go to step 6 .
5. Turn OFF the engine. Inspect the O2S for proper installation. Ensure electrical connectors and wires are secured and not contacting the exhaust system. Did you find and correct the condition? If yes, go to step 7 . If no, diagnose fuel system. See appropriate BASIC DIAGNOSTIC PROCEDURES article.
6. Inspect for the following conditions: Excessive fuel in the crankcase. The evaporative emissions control system. The fuel pressure regulator for proper operation. Ensure that all injectors are functioning properly. Perform the Fuel Injector Balance Test. Did you find and correct the condition? If yes, go to next step. If no, see appropriate article in ENGINES.
7. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
8. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Fuel contamination, such as water and alcohol, will affect fuel trim.
2. The system will go rich if injectors are supplying too much fuel.
3. Using a scan tool, review the Failure Records. If an intermittent condition is suspected, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The engine is running.
2. The ignition voltage is between 9-18 volts.

1. The PCM detects an incorrect voltage on the fuel injector control circuit.
2. The condition exists for 30 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Clear the DTCs with a scan tool. Idle the engine at the normal operating temperature. Monitor the misfire current counters with a scan tool. Are any of the counters incrementing? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S09756472022002012100000) .
4. Turn OFF the ignition. Disconnect the fuel injector harness multi-way connector. Probe the appropriate fuel injector control circuit, PCM side, with a test lamp connected to battery voltage. Crank the engine. Does the test lamp flash when cranking the engine? If yes, go to step 8 . If no, go to next step.
5. Does the test lamp remain illuminated at all times? If yes, go to step 7 . If no, go to next step.
6. Test the control circuit of the fuel injector for a short to voltage or an open between the multi-way connector and the PCM. Did you find and correct the condition? If yes, go to step 18 . If no, go to step 14 .
7. Test the control circuit of the fuel injector for a short to ground between the multi-way connector and the PCM. Did you find and correct the condition? If yes, go to step 18 . If no, go to step 17 .
8. Inspect the accessible fuel injector jumper harness between the multi-way connector and the intake manifold for the following: Poor connections at the multi-way connector. Damaged or pinched wiring. Broken wires inside the insulation. Did you find and correct the condition? If yes, go to step 18 . If no, go to next step.
9. Probe the appropriate fuel injector control circuit, fuel injector side, at the multi-way connector, with a test lamp connected to battery voltage. Does the test lamp illuminate? If yes, go to step 15 . If no, go to next step.
10. With a DMM, test for continuity between the ignition 1 voltage supply terminal and the appropriate fuel injector control circuit terminal, at the multi-way connector. Does the DMM indicate OL? If yes, go to next step. If no, go to step 13 .
11. Test the control circuit of the fuel injector for an open or for poor connections at the fuel injector. Did you find and correct the condition? If yes, go to step 18 . If no, go to next step.
12. Test the ignition 1 voltage supply circuit of the fuel injector for an open between the fuel injector and the splice. Did you find and correct the condition? If yes, go to step 18 . If no, go to step 16 .
13. Test the control circuit of the fuel injector for a short to voltage or a short to another circuit. Did you find and correct the condition? If yes, go to step 18 . If no, go to step 16 .
14. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 18 . If no, go to step 17 .
15. Repair the short to ground in the fuel injector control circuit. After repairs, go to step 18 .
16. Replace the appropriate fuel injector. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 18 .
17. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
18. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
19. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Performing the Fuel Injector Coil test may help isolate an intermittent condition. See appropriate SYSTEM & COMPONENT TESTING article.
2. For an intermittent condition, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

Note. If start-up ECT is less than 20°F (7°C), misfire detection is delayed until Engine Coolant Temperature (ECT) is more than 70°F (21°C). If start-up ECT is more than 20°F (7°C), misfire detection begins after a 5 second delay.

1. DTCs P0013, P0014, P0105, P0107, P0108, P0117, P0118, P0122, P0123, P0125, P0128, P0217, P0218, P0336, P0340, P0341, P0365, P0366, P0502, P0503, P1114, P1115, P1121, P1122, P1336, or P1345 are not set.
2. The engine is running.
3. The system voltage is 10-18 volts.
4. The Engine Coolant Temperature (ECT) is 19-266°F (7-130°C).
5. The throttle angle is steady.
6. The A/C compressor clutch is not changing state.
7. The Exhaust Gas Recirculation (EGR) flow test is inactive.
8. The fuel level is above 10 percent.
9. The fuel cut-off or decel fuel cut-off (DFCO) mode is not active.

1. The PCM determines that an emission type misfire is present on more than 1 cylinder.
2. The PCM determines that a catalyst damaging misfire is present.

1. If the misfire level is non-catalyst damaging, the PCM will illuminate the MIL during the second key cycle in which the DTC sets.
2. If the misfire is severe enough to cause possible catalyst damage, the PCM will immediately flash the MIL while the misfire remains at catalyst damaging levels.
3. The PCM will disable the Torque Converter Clutch (TCC) operation.
4. The PCM will store the conditions present when the DTC set as Freeze Frame/Failure Records data. Any data previously stored in Freeze Frame will be overwritten when this DTC sets. The only exception to this is if a fuel trim DTC was already recorded in Freeze Frame. In this case, the fuel trim data stays in Freeze Frame and the Misfire Data will be stored in Failure Records.

1. The PCM will turn the MIL OFF after three consecutive trips during which the diagnostic runs and passes. Note that if the last failure was during a non-typical driving condition, the MIL may remain ON longer than three drive trips. Review Freeze Frame for the last failure conditions.
2. The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using the scan tool Clear DTC Information function.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are any other DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Start the engine. Select the Misfire Bar Graph on the scan tool. The Misfire Current counters can also be used. Do any cylinders indicate an excessive amount of misfire? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
4. Does the misfire appear to be affecting specific cylinders? If yes, go to step 8 . If on, go to next step.
5. Inspect the following system grounds: PCM grounds. Ignition control module grounds. Ensure that the grounds are clean, tight, and in their proper locations. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
6. Test the fuel pressure. See appropriate BASIC DIAGNOSTIC PROCEDURES article. If a fuel system pressure condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
7. Test for excessive water, alcohol, or other contaminants. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
8. Inspect the following areas for vacuum leaks: Vacuum leaks between the intake manifold and the cylinder head. Injector O-rings. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
9. Test for proper fuel injector operation. See appropriate SYSTEM & COMPONENT TESTING article. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
10. Test for proper ignition system operation. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
11. Inspect and/or test for the following mechanical problems: A damaged accessory drive belt or pulley. A damaged driven accessory, such as a generator, a water pump, a drive belt a tensioner, etc. A loose or broken motor mount. A base engine mechanical problem. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Test for proper transaxle TCC operation. See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS. If a condition is found, repair as necessary. Did you find and correct the condition? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Check for the following conditions

1. Incorrect CKP system variation data stored in the PCM. Run the CKP System Variation Learn Procedure using the scan tool. See «CRANKSHAFT POSITION SENSOR»(ref-132531-S34845224152002012100000) under PROGRAMMING.
2. System grounds. Ensure that all connections are clean and properly tightened.
3. Damaged accessory drive belt or driven accessory. A damaged serpentine belt or belt driven accessory can cause engine load variations sufficient to set a misfire DTC.
4. Fuel pressure. Perform a fuel system pressure test. A malfunctioning fuel pump, plugged filter, or malfunctioning fuel system pressure regulator will contribute to a lean condition. See appropriate BASIC DIAGNOSTIC PROCEDURES article.
5. Fuel injectors. See appropriate SYSTEM & COMPONENT TESTING article.
6. Contaminated fuel.
7. Extended idle. Excessive Open Loop operation caused by extended idling or short trip driving may leave deposits on the Heated Oxygen Sensors (HO2S). The deposits cause oxygen sensors to respond slowly to exhaust oxygen content, affecting fuel control and causing a misfire to be indicated at idle. This condition is not permanent. To determine if this condition is causing the DTC P0300 to be set, review the Freeze Frame/Failure Records data for DTC P0300. If the DTC P0300 occurs at high engine speeds, the condition described above did not cause the DTC P0300 to set. If the DTC P0300 occurs at idle or very low engine speeds and at engine coolant temperatures below 176°F (80°C), the condition described above is very likely the cause of the DTC P0300 being set. The deposits on the heated oxygen sensors can be eliminated by operating the vehicle fully warm at mass air flows above 15 g/s.
8. Running the vehicle low on fuel. This DTC may set if the vehicle misfires while running out of fuel. If no misfire is currently present, but the History Counters indicate random misfire was once present, ask if the vehicle has been run out of fuel. If this is the case, no further repair may be necessary.

Note. If the level of misfire was sufficient to cause possible catalyst damage, if the MIL was flashing, ensure that the DTC P0420 test is completed and passed after verifying the misfire repair. See DTC P0420: TWC SYSTEM - LOW EFFICIENCY .

If the condition is intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0013, P0014, P0105, P0107, P0108, P0117, P0118, P0122, P0123, P0125, P0128, P0217, P0218, P0336, P0340, P0341, P0365, P0366, P0502, P0503, P1114, P1115, P1121, P1122, P1336, and P1345 are not set.
2. The engine is running.
3. The system voltage is 10-18 volts.
4. The Engine Coolant Temperature (ECT) is 19-266°F (7-130°C).
5. The throttle angle is steady.
6. The A/C compressor clutch is not changing state.
7. The Exhaust Gas Recirculation (EGR) flow test is inactive.
8. The fuel level is above 10 percent.
9. The fuel cut-off or decel fuel cut-off (DFCO) mode is not active.

1. The PCM determines that an emission type misfire is present.
2. The PCM determines that a catalyst damaging misfire is present.

1. If the misfire level is non-catalyst damaging, the PCM will illuminate the MIL during the second key cycle in which the DTC sets.
2. If the misfire is severe enough to cause possible catalyst damage, the PCM will immediately flash the MIL while the misfire remains at catalyst damaging levels.
3. The PCM will disable the Torque Converter Clutch (TCC) operation.
4. The PCM will store the conditions present when the DTC set as Freeze Frame/Failure Records data. Any data previously stored in Freeze Frame will be overwritten when this DTC sets. The only exception to this is if a fuel trim DTC was already recorded in Freeze Frame. In this case, the fuel trim data stays in Freeze Frame and the Misfire Data will be stored in Failure Records.

1. The PCM will turn the MIL OFF after three consecutive trips during which the diagnostic runs and passes. Note that if the last failure was during a non-typical driving condition, the MIL may remain ON longer than three drive trips. Review Freeze Frame for the last failure conditions.
2. The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using the scan tool Clear DTC Information function.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Check for other DTCs that may cause a misfire. Did you find any other DTCs? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Connect the scan tool. Start the engine. Allow the engine to idle or operate within the conditions listed in the Freeze Frame records. Using the scan tool, monitor the Misfire Current Counter for this cylinder. Is the Misfire Current Counter incrementing? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S16347984082002012400000) .
4. Inspect the following items: The vacuum hoses for splits, kinks and proper connections. The throttle body and the intake manifold for vacuum leaks. The crankcase ventilation valve and/or system for vacuum leaks. Ensure that the PCM grounds are clean and secure. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
5. Perform the Fuel Injector Balance Test and the Fuel Injector Coil Test on the affected cylinder. See appropriate SYSTEM & COMPONENT TESTING article. Repair as necessary. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
6. Perform the Ignition System Check on the affected cylinder. See appropriate SYSTEM & COMPONENT TESTING article. Repair as necessary. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
7. Turn OFF the ignition. Disconnect the HO2S 1 connector. Start the engine and allow the engine to idle. Using the scan tool, monitor the Misfire Current Counter for this cylinder. Is the Misfire Current Counter incrementing? If yes, see appropriate article in ENGINES. If no, see «DTC P0130: CLOSED LOOP RATIONALITY»(ref-132531-S12952865232002012300000) .
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Check for the following conditions

1. Incorrect CKP system variation data stored in the PCM. Run the CKP System Variation Learn Procedure using the scan tool. See «CRANKSHAFT POSITION SENSOR»(ref-132531-S34845224152002012100000) under PROGRAMMING.
2. System grounds. Ensure that all connections are clean and properly tightened.
3. Damaged accessory drive belt or driven accessory. A damaged serpentine belt or belt driven accessory can cause engine load variations sufficient to set a misfire DTC.
4. Fuel pressure. Perform a fuel system pressure test. See appropriate BASIC DIAGNOSTIC PROCEDURES article. A malfunctioning fuel pump, plugged filter, or malfunctioning fuel system pressure regulator will contribute to a lean condition.
5. Fuel injectors.
6. Contaminated fuel.
7. Extended idle. Excessive Open Loop operation caused by extended idling or short trip driving may leave deposits on the Heated Oxygen Sensors (HO2S). The deposits cause oxygen sensors to respond slowly to exhaust oxygen content, affecting fuel control and causing a misfire to be indicated at idle. This condition is not permanent. To determine if this condition is causing the DTC P0300 to be set, review the Freeze Frame/Failure Records data for DTC P0300. If the DTC P0300 occurs at high engine speeds, the condition described above did not cause the DTC P0300 to set. If the DTC P0300 occurs at idle or very low engine speeds and at engine coolant temperatures below 176°F (80°C), the condition described above is very likely the cause of the DTC P0300 being set. The deposits on the heated oxygen sensors can be eliminated by operating the vehicle fully warm at mass air flows above 15 g/s.
8. Running the vehicle low on fuel. This DTC may set if the vehicle misfires while running out of fuel. If no misfire is currently present, but the History Counters indicate random misfire was once present, ask if the vehicle has been run out of fuel. If this is the case, no further repair may be necessary.

Note. If the level of misfire was sufficient to cause possible catalyst damage (if the MIL was flashing), ensure that the DTC P0420 test is completed and passed after verifying the misfire repair. See DTC P0420: TWC SYSTEM - LOW EFFICIENCY .

If the condition is intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0117, P0118, P0122, P0123, P0327, or P0332 are not set.
2. The engine run time is more than 20 seconds.
3. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
4. The engine speed is between 2000-6400 RPM.
5. The manifold absolute pressure (MAP) is more than 60 kPa.

The PCM detects a malfunction in the KS diagnostic circuitry that will not allow proper diagnosis of the KS system.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has run and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn the MIL OFF during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. Use the scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close as possible to the Freeze Frame/Failure Records data that you observed. Did the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
3. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
4. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
5. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The knock sensor must be torqued correctly to 18 ft. lbs. (25 N.m).
2. The mounting between the sensor and the engine must be free of burrs, casting flash, and foreign material.
3. The knock sensor head must be clear of the hoses, the brackets, and the engine electrical wiring.

1. DTCs P0117, P0118, P0122, and P0123 are not set.
2. The ignition voltage is more than 10 volts.
3. The Engine Coolant Temperature (ECT) sensor is more than 158°F (70°C).
4. The engine run time is more than 20 seconds.
5. The manifold absolute pressure (MAP) is more than 60 kPa.
6. The engine speed is between 2000-6400 RPM.

The knock sensor signal is outside the normal operating range or the knock sensor signal is not present.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Observe the Freeze Frame/Failure Records data for this DTC. Turn the ignition OFF for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
3. Turn OFF the ignition. Disconnect the affected knock sensor. Turn ON the ignition, with the engine OFF. Measure the voltage at the signal circuit of the knock sensor harness to a good ground with a DMM. Measure the voltage at the low reference circuit of the knock sensor harness to a good ground with a DMM. Does the DMM display a voltage above 1 V on either circuit? If yes, go to step 8 . If no, go to next step.
4. Turn OFF the ignition. Measure the resistance between the signal circuit of the knock sensor harness and the low reference circuit of the knock sensor harness on the PCM side. Does the DMM display OL or infinite? If yes, go to step 6 . If no, go to next step.
5. Disconnect the PCM. Test the signal circuit of the knock sensor for a short to ground. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 7 .
6. Test the signal circuit and the low reference circuit of the knock sensor for an open. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
7. Connect PCM. Connect a DMM between the terminals of the knock sensor harness connector on the sensor side. Set the DMM to the AC scale. Start the engine. Observe the DMM while accelerating the engine briefly from idle to wide open throttle. Does the voltage go from below 25 mV at idle to above 60 mV at wide open throttle? If yes, go to step 9 . If no, go to step 10 .
8. Repair the short to voltage in the signal circuit of the knock sensor or the low reference circuit of the knock sensor. After repairs, go to step 13 .
9. Repair the poor connection at the knock sensor harness connector. After repairs, go to step 13 .
10. Replace the knock sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
11. Test for an intermittent and for a poor connection at the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to next step.
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The knock sensor must be correctly tightened to 18 ft. lbs. (25 N.m).
2. The mounting between the sensor and engine must be free of burrs, casting flash, and foreign material.
3. The knock sensor head is clear from hoses, brackets, and engine wiring.
4. If the knock sensor is dropped it must be replaced.
5. For an intermittent condition, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The engine is running.
2. The battery voltage is below 18 volts.
3. DTC P0562 is not set.

The crank sensor signal is not being detected.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Start the engine. Observe the CKP active counter on the scan tool. Does the CKP active counter increment? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S01398319622002012100000) .
4. Disconnect the PCM harness from the PCM. Connect the Digital Multimeter (DMM) between the CKP sensor circuits, set to the ohm scale. Is the resistance 500-900 ohms? If yes, go to next step. If no, go to step 6 .
5. Test the CKP circuits for a short to ground. Repair the condition as necessary. Did you find and correct the condition? If yes, go to step 11 . If no, go to step 9 .
6. Test the CKP circuits for the following conditions: A short to voltage. An open. A short across circuits. A high resistance. Repair the condition as necessary. Did you find and correct the condition? If yes, go to step 11 . If no, go to next step.
7. Inspect for poor connections at the CKP sensor. After repairs, go to step 11 . If no, go to next step.
8. Replace the CKP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 11 .
9. Inspect for faulty connections at the PCM. Did you find and correct the condition? If yes, go to step 11 . If no, go to next step.
10. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
11. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
12. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. If the DTC is determined to be intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. An intermittent can also be the result of a defective reluctor wheel. Remove the crankshaft sensor and inspect the reluctor wheel through the hole.

1. The engine is running.
2. DTCs P0340 or P0341 are not set.

The CKP resync counter goes more than 15 times within 4 minutes and 15 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Attempt to start the engine. Will the engine start? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S34626661012002012100000) .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC failed this ignition? If yes, go to next step. If no, go to step 5 .
4. With the engine running, wiggle the electrical connectors of the following components and related circuits while listening for the engine to stumble: The PCM The CKP Does the engine stumble? If yes, go to step 6 . If no, go to step 7 .
5. Operate any non-engine related electronic component on the vehicle. Observe the Med. Resolution Resync Counter with the scan tool. Does the Med. Resolution Resync Counter on the scan tool increment while operating any non-engine related electronic components? If yes, go to step 9 . If no, go to step 4 .
6. Turn OFF the ignition. Check for a poor electrical terminal connection or replace the terminal in the circuit which caused the engine to stumble. Repair the electrical connection or the terminal in the circuit as necessary. After repairs, go to step 12 .
7. Did the MIL illuminate in Step 3 ? If yes, go to next step. If no, go to step 12 .
8. Turn OFF the ignition. Check the following items for rubbed-through wire insulation or for wiring being pinched: The PCM. The CKP sensor. Repair the wiring as necessary. After repairs, go to step 12 . If no, go to step 10 .
9. Turn OFF the ignition. Repair the circuitry of the malfunctioning or interfering component. Move any wiring that is causing the interference away from the CKP and the ICM wiring harness. After repairs, go to step 12 .
10. Replace the CKP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Idle the engine for 5 minutes, or until the Malfunction Indicator Lamp (MIL) turns ON. Did the MIL illuminate? If yes, go to next step. If no, go to step 12 .
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. If the DTC is determined to be intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. An intermittent can also be the result of a defective reluctor wheel. Remove the crankshaft sensor and inspect the reluctor wheel through the hole.

The engine is running.

The CMP Active Counter is not incrementing.

1. The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.
2. The PCM records the operating conditions at the time when the diagnostic fails. This information stores in the Freeze Frame and Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after three consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool to clear the DTCs

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect the scan tool. Start and idle the engine. Use a scan tool in order to monitor the CMP active counter. Does the scan tool indicate the CMP active counter is incrementing? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observe. Does the DTC reset? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S13239310042002012500000) .
4. Turn OFF the ignition. Disconnect the CMP sensor connector. Turn ON the ignition, with the engine OFF. With a test lamp connected to ground, touch the 12-volt reference circuit. Does the test lamp illuminate? If yes, go to step 6 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the PCM connector C2. Test the 12-volt circuit of the CMP sensor for a short to ground, high-resistance, or an open. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 14 .
6. Connect a test lamp to battery voltage. Touch the CMP sensor low reference circuit. Does the test lamp illuminate? If yes, go to step 8 . If no, go to next step.
7. Turn OFF the ignition. Disconnect the PCM connector C2. Test the low reference circuit of the CMP sensor for an open. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 14 .
8. Start the engine. Monitor the CMP active counter on the scan tool. Momentarily and repeatedly probe the CMP sensor signal circuit at the CMP harness connector with a test lamp connected to battery positive voltage. Does the CMP active counter change when performing this test? If yes, go to step 12 . If no, go to next step.
9. Did the fuse in the jumper wire open? If yes, go to step 11 . If no, go to next step.
10. Test the signal circuit of the CMP sensor for a short to voltage or an open. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 14 .
11. Test the signal circuit of the CMP sensor for a short to ground. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
12. Inspect for poor connections at the CMP sensor. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
13. Replace the CMP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 16 .
14. Inspect for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
15. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
16. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
17. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Whenever the PCM sees less than 15 resyncs in 256 seconds, the counter resets to 0. When a poor connection is present, the cam sensor active counter stops incrementing and the cam sensor resync counter starts to increment.
2. Inspect the wiring harness for damage. If the harness appears to be okay, observe the CMP resync counter on the scan tool while moving connectors and wiring harnesses related to the CMP sensor. If the CMP resync counter still does not count, then while still observing the scan tool, operate any non-engine related electrical components on the vehicle. A change in display will indicate the location of the malfunction.
3. A defective reluctor wheel or a cracked or damaged CMP sensor can result in an intermittent. Remove the camshaft sensor and inspect for any damage. With the CMP sensor removed you can also inspect the reluctor wheel through the hole. Check the porosity and condition of the wheel. The edges must be square. Look for a nicked or damaged wheel.
4. If the DTC is determined to be intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

The engine is running.

The PCM sees more than 15 CMP sensor resyncs in 256 seconds (4 minutes 16 seconds).

1. The Malfunction Indicator Lamp (MIL) will illuminate after 2 consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. The Freeze Frame and Failure Records buffers will store this information.
3. A history DTC stores.

1. The MIL will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm up cycles without a fault.
3. A scan tool can clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. Connect a scan tool. Are any other DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Start the engine. Allow the engine to idle. Observe the CMP Resync Counter with the scan tool. Is the CMP Resync Counter incrementing? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S16873913212002012100000) .
4. Turn OFF the ignition. Disconnect the CMP sensor electrical connector. Start the engine. Observe CMP Resync on the scan tool. Did the CMP Resync Counter stop incrementing? If yes, go to next step. If no, go to step 6 .
5. Turn OFF the engine. With the CMP connector still disconnected, connect a Digital Multimeter (DMM) set to the DC HZ scale from the CMP signal circuit (PCM side) to ground. Start and idle the engine. Does the DMM display a Hertz reading above 0 Hz? If yes, go to next step. If no, go to step 7 .
6. Inspect the CMP sensor harness for incorrect routing at the following locations, or shorted to another circuit that generates frequency: Secondary ignition wires or coils. Solenoids. Relays. Motors. Did you locate and correct the condition? If yes, go to step 11 . If no, go to step 9 .
7. Turn OFF the ignition. Check for a faulty electrical connection at the CMP sensor electrical connector. Repair the electrical connector as necessary. Did you find and correct the condition? If yes, go to step 11 . If no, go to next step.
8. Replace the camshaft position (CMP) sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 11 .
9. Disconnect the PCM electrical connector. Check the PCM terminals for a faulty electrical connection. Repair the terminals as necessary. Did you find and correct the condition? If problem was found, go to step 11 . If problem was not found, go to next step.
10. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
11. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
12. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. If the PCM sees less than 15 resyncs in 256 seconds, the counter is reset to 0. When a faulty electrical connection is present, the CMP Reference Activity counter will stop incrementing and the CMP Resync Counter will increment.
2. If the DTC is determined to be intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0122, P0123, P0131, P0132, P0133, P0134, P0135, P0137, P0138, P0140, P0141, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0326, P0327, P0332, P0336, P0340, P0341, P0440, P0442, P0446, P0452, P0453, P0495, P0502, P0503, P0507, P0601, P0602, P0604, P0606, P1120, P1133, P1220, P1221, P1271, P1275, P1280, P1441, P1481, P1482, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The engine speed is more than 1000 RPM for a minimum of 36 seconds since the end of the last idle period.
3. The Barometric (BARO) pressure is more than 72 kPa.
4. The Intake Air Temperature (IAT) is between -5-176°F (-20.5-80.0°C).
5. The Engine Coolant Temperature (ECT) is between 158-257°F (70-125°C).
6. The battery voltage is more than 9 volts.
7. The calculated air flow is less than 15 g/sec.
8. The engine run time is more than 530 seconds.
9. The vehicle speed is less than 3 MPH.
10. Tests attempted this trip are less than 12.
11. Predicted catalyst temperature is between 934-1382°F (501-750°C).

The PCM determines that the oxygen storage capacity of the three-way catalytic converter (TWC) is degraded past a calibrated value.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) the first time the diagnostic runs and fails.
2. The control module will set the DTC and records the operating conditions at the time the diagnostic fails. The control module stores the failure information in the scan tools Freeze Frame/Failure Records.

1. The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed.
2. A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 40°F (22°C) from the start-up coolant temperature and the engine coolant reaches a temperature that is more than 158°F (70°C) during the same ignition cycle.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are any other DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Test the exhaust system for the following: Leaks. Loose or missing hardware. Repair as necessary. Did you find a problem? If yes, go to step 5 . If no, go to next step.
4. Verify that the correct original equipment three-way catalytic converter is installed. Test the converter for the following: Dents. Severe discoloration. Holes. Ensure that oxygen sensors are properly installed and that wiring connections are undamaged and properly retained and not damaged. Repair as necessary. Did you find a problem? If yes, go to next step. If no, go to step 6 .
5. Using the scan tool, clear the DTCs. Start the engine. Allow the engine to idle until the engine reaches normal operating temperature. Select DTC and the Specific DTC function. Enter the DTC number which was set. Operate the vehicle within the conditions for setting this DTC, until the scan tool indicates the diagnostic Ran. Does the scan tool indicate that this diagnostic Passed? If yes, system is okay. If no, go to step 2 .
6. Replace the catalytic converter. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repair, system is okay.

Fuel with a high sulfur or lead content can degrade marginal converter's performance. Be sure to check the fuel quality.

An intermittent may be caused by any of the following conditions

1. A poor connection.
2. Rubbed through wire insulation.
3. A broken wire inside the insulation.

Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Repair the circuits as necessary.

1. DTC P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0125, P0452, and P0453 are not set.
2. The ignition voltage is between 10-18 volts.
3. The Barometric (BARO) pressure is more than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The Engine Coolant Temperature (ECT) is between 39-86°F (4-30°C).
6. The Intake Air Temperature (IAT) is between 39-86°F (4-30°C).
7. The start up ECT and IAT are within 16°F (9°C) of each other.
8. The Vehicle Speed Sensor (VSS) is less than 75 MPH.

The EVAP system is not able to achieve or maintain vacuum during the diagnostic test.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test ran and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn the Malfunction Indicator Lamp (MIL) OFF during the first consecutive trip in which the diagnostic has been run and passed.
2. A last test failed (current DTC) clears when the PCM turns OFF the MIL.
3. The history DTC will clear after the PCM runs and passes 40 consecutive warm up cycles with no failure.
4. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P0446, P0452, P0453, or P1441 also set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Inspect the EVAP system for the following conditions: A loose, incorrect, faulty, or missing fuel tank fill cap. Damaged or disconnected EVAP system purge lines. A damaged EVAP system component. A loose, missing, or damaged service port Schrader valve. Did you find and correct the condition? If yes, go to step 31 . If no, go to next step.
4. Use the scan tool in order to clear the DTCs. Command the EVAP canister purge valve to 50 percent and back to 0 percent with the scan tool. Do you hear or feel a clicking from the EVAP purge valve when the purge valve is commanded to 50 percent? If yes, go to next step. If no, go to step 6 .
5. Command the EVAP canister vent valve ON and OFF with the scan tool. Do you hear or feel a click as the EVAP vent valve is commanded ON and OFF? If yes, go to step 10 . If no, go to step 8 .
6. Disconnect the EVAP purge valve harness connector. Turn ON the ignition, with engine OFF. Connect a test lamp between the ignition voltage circuit of the EVAP purge valve and a known-good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 22 .
7. Connect a test lamp between the ignition voltage circuit and the control circuit of the EVAP purge valve. Command the EVAP purge valve to 50 percent and then to 0 percent with a scan tool. Does the test lamp illuminate or pulsate when the EVAP purge valve is commanded to 50 percent and turn OFF when the EVAP purge valve is commanded to 0 percent? If yes, go to step 18 . If no, go to step 16 .
8. Turn ON the ignition, with the engine OFF. Disconnect the EVAP vent valve harness connector. Connect a test lamp between the EVAP vent valve ignition voltage circuit and a good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 23 .
9. Connect the test lamp between the ignition voltage circuit and the control circuit of the EVAP vent valve. Command the EVAP vent valve ON with a scan tool. Does the test lamp illuminate when the EVAP vent valve is commanded ON? If yes, go to step 19 . If no, go to step 17 .
10. Turn OFF the ignition. Disconnect the EVAP purge pipe from the EVAP purge valve. Connect a vacuum gauge directly to the EVAP purge port of the EVAP purge valve. Start and idle the engine. Command the EVAP canister purge valve to 50 percent with a scan tool. Is the vacuum equal to or more than 15 in. H2O? If yes, go to next step. If no, go to step 21 .
11. Reconnect the EVAP purge pipe to the EVAP canister purge valve. Install the fuel tank cap adapter. Connect the EVAP pressure/purge diagnostic station to the fuel tank cap adapter. Turn ON the ignition, with the engine OFF. Use a scan tool in order to seal the EVAP system. Using the EVAP diagnostic station, attempt to pressurize the EVAP system to the specified value. Rotate the EVAP diagnostic station rotary switch to the OFF/HOLD position. Were you able to obtain and hold 5 in. H2O for 1 minute? If yes, go to next step. If no, go to step 13 .
12. Compare the EVAP diagnostic station pressure gage value to the scan tool Fuel Tank Pressure (FTP) sensor value. Is the EVAP pressure/purge diagnostic station gage value near the FTP sensor scan tool value? If yes, go to step 14 . If no, go to step 29 .
13. With the pressure/purge diagnostic station, continuously attempt to pressurize the EVAP system. With the J 41416 ultrasonic leak detector, inspect for leaks in the following locations: The EVAP system purge pipe. The EVAP vapor pipe. The EVAP vent hose/pipe. The fuel fill pipe/hose and fuel fill cap. The EVAP canister. The EVAP canister vent valve. The EVAP canister purge valve. The fuel sender assembly and/or seal. The FTP sensor seal. The fill limiter vent valve, pressure relief valve, rollover valves, and fuel tank. Did you find and repair the condition? If yes, go to step 31 . If no, see «DIAGNOSTIC AIDS»(ref-132531-S00846680902002012100000) .
14. Observe the EVAP diagnostic station pressure gage. Disconnect the EVAP purge pipe from the EVAP canister. Does the EVAP pressure/purge diagnostic station gage decrease to near 0 in. H2O? If yes, go to step 24 . If no, go to next step.
15. Observe the pressure gage on the EVAP diagnostic station. Disconnect the EVAP vapor pipe from the EVAP canister. Does the EVAP pressure/purge diagnostic station gage decrease to near 0 in. H2O? If yes, go to step 28 . If no, go to step 25 .
16. Test the control circuit of the EVAP purge valve for an open or short to voltage. Did you find and correct the condition? If yes, go to step 31 . If no, go to step 20 .
17. Test the control circuit of the EVAP vent valve for an open or short to voltage. Did you find and correct the condition? If yes, go to step 31 . If no, go to step 20 .
18. Test for poor connections at the harness connector of the EVAP purge valve. Did you find and correct the condition? If yes, go to step 31 . If no, go to step 26 .
19. Test for poor connections at the harness connector of the EVAP vent valve. Did you find and correct the condition? If yes, go to step 31 . If no, go to step 27 .
20. Test for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 31 . If no, go to step 30 .
21. Inspect the vacuum source to the EVAP purge valve for blockage, cuts, or disconnects. Repair as necessary. Did you find and correct the condition? If yes, to step 31 . If no, go to step 26 .
22. Repair the ignition voltage circuit of the EVAP purge valve for an open or short to ground. Replace the fuse if necessary. After repair, go to step 31 .
23. Repair the ignition voltage circuit of the EVAP vent valve for an open or short to ground. Replace the fuse if necessary. After repair, go to step 31 .
24. Repair the restriction in the EVAP purge pipe. See EVAPORATIVE EMISSION SYSTEM CLEANING in REMOVAL, OVERHAUL & INSTALLATION. After repairs, go to step 31 .
25. Repair the restriction in the EVAP vapor pipe. After repairs, go to step 31 .
26. Replace the EVAP canister purge valve. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 31 .
27. Replace the EVAP vent valve. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 31 .
28. Replace the EVAP canister. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 31 .
29. Replace the FTP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 31 .
30. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
31. Turn ON the ignition, with the engine OFF. Command the EVAP vent valve ON with a scan tool. Pressurize the EVAP system to 5 in. H2O with the EVAP pressure/purge diagnostic station. Place the control knob on the EVAP pressure/purge diagnostic station to the OFF/HOLD position. Monitor the EVAP system pressure on the EVAP pressure/purge diagnostic station for 5 minutes. Does the EVAP system pressure remain constant? If yes, go to next step. If no, go to step 4 .
32. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.
2. Use the J 41413 EVAP Pressure/Purge Diagnostic Station in order to pressurize the EVAP system to aid in locating intermittent leaks. Move all EVAP components while testing with the J 41416 Ultrasonic Leak Detector.
3. A temporary blockage in the EVAP canister purge valve, purge pipe, or EVAP canister could cause an intermittent condition. To repair a blockage in the EVAP system, See EVAPORATIVE EMISSION SYSTEM CLEANING in REMOVAL, OVERHAUL & INSTALLATION.

1. DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0125, P0440, P0452, or P0453 are not set.
2. The ignition voltage is between 10-18 volts.
3. The Barometric (BARO) pressure is more than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The Engine Coolant Temperature (ECT) is between 39-86°F (4-30°C).
6. The Intake Air Temperature (IAT) is between 39-86°F (4-30°C).
7. The start up ECT and IAT are within 16°F (9°C) of each other.

The EVAP system is not able to maintain vacuum during the diagnostic test.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test ran and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn the MIL OFF during the first consecutive trip in which the diagnostic has been run and passed.
2. A last test failed (current DTC) clears when the PCM turns OFF the MIL.
3. The history DTC will clear after the PCM runs and passes 40 consecutive warm up cycles with no failure.
4. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P0440, P0446, P0452, P0453, or P1441 also set? If yes, see «DTC P0440: EVAP SYSTEM - LARGE LEAK»(ref-132531-S08416807372002012100000) , «DTC P0446: EVAP VENT VALVE PERFORMANCE»(ref-132531-S22995030982002012100000) , «DTC P0452: FUEL TANK PRESSURE SENSOR - LOW VOLTAGE»(ref-132531-S42569336432002012100000) , «DTC P0453: FUEL TANK PRESSURE SENSOR - HIGH VOLTAGE»(ref-132531-S30789581442002012100000) or «DTC P1441: EVAP SYSTEM FLOW DURING NON-PURGE»(ref-132531-S12478573952002012100000) . If no, go to next step.
3. Inspect the EVAP system for the following conditions: A loose, incorrect, faulty, or missing fuel tank fill cap. Damaged or disconnected EVAP system purge lines. A damaged EVAP system component. A loose, missing, or damaged service port Schrader valve. Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.
4. Install the fuel tank cap adapter. Connect the EVAP pressure/purge diagnostic station and the fuel tank cap to the fuel tank cap adapter. Turn ON the ignition, with the engine OFF. Use a scan tool to clear the DTCs from the PCM. Command the EVAP vent valve ON with a scan tool. Pressurize the EVAP system to 5 in. H2O with the EVAP pressure/purge diagnostic station. Place the control knob on the EVAP pressure/purge diagnostic station to the OFF/HOLD position. Monitor the EVAP system pressure on the EVAP pressure/purge diagnostic station for 5 minutes. Does the EVAP system pressure remain constant? If yes, see «DIAGNOSTIC AIDS»(ref-132531-S26430144792002012100000) . If no, go to next step.
5. With the pressure/purge diagnostic station, continuously attempt to pressurize the EVAP system. With the J 41416 ultrasonic leak detector inspect for leaks in the following locations: The EVAP system purge pipe. The EVAP vapor pipe. The EVAP vent hose/pipe. The fuel fill pipe/hose and fuel fill cap. The EVAP canister. The EVAP canister vent valve. The EVAP canister purge valve. The fuel sender assembly and/or seal. The FTP sensor seal. The fill limiter vent valve, pressure relief valve, rollover valves, and fuel tank. Did you find and repair the condition? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S26430144792002012100000) .
6. Turn ON the ignition, with the engine OFF. With a scan tool, clear the DTCs. Command the EVAP vent valve ON with a scan tool. Pressurize the EVAP system to 5 in. H2O with the EVAP pressure/purge diagnostic station. Place the control knob on the EVAP pressure/purge diagnostic station to the OFF/HOLD position. Monitor the EVAP system pressure on the EVAP pressure/purge diagnostic station for 5 minutes. Does the EVAP system pressure remain constant? If yes, go to next step. If no, go to step 2 .
7. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Note. If carbon release is detected, see EVAPORATIVE EMISSION SYSTEM CLEANING in REMOVAL, OVERHAUL & INSTALLATION.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

To aid in locating an intermittent leak, use the J 41413 EVAP Pressure/Purge Diagnostic Station to pressurize the EVAP system. Move all EVAP system components while testing with the J 41416 Ultrasonic Leak Detector.

1. DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0122, P0123, P0452, or P0453 are not set.
2. The ignition voltage is between 10-18 volts.
3. The Barometric (BARO) pressure is more than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The Engine Coolant Temperature (ECT) is between 39-86°F (4-30°C).
6. The Intake Air Temperature (IAT) is between 39-86°F (4-30°C).
7. The start up ECT and IAT are within 16°F (9°C) of each other.
8. The Vehicle Speed Sensor (VSS) is less than 75 MPH.

1. The Fuel Tank Pressure (FTP) is less than -10 in. H2O.
2. The condition is present for at least 30 seconds.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has run and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The Powertrain Control Module (PCM) will turn OFF the MIL during the first trip in which the diagnostic has been run and passed.
2. The history DTC will clear when the PCM turns OFF the MIL.
3. The DTC can be cleared by using the scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Did DTCs P0452 or P0453 also set? If yes, see «DTC P0452: FUEL TANK PRESSURE SENSOR - LOW VOLTAGE»(ref-132531-S42569336432002012100000) or «DTC P0453: FUEL TANK PRESSURE SENSOR - HIGH VOLTAGE»(ref-132531-S30789581442002012100000) . If no, go to next step.
3. Inspect the EVAP system for the following conditions: A damaged EVAP vent valve. A pinched EVAP vent hose. Did you find and correct the condition? If yes, go to step 19 . If no, go to next step.
4. Install the J 41415-40 Fuel Tank Cap Adapter to the fuel filler neck. Install the J 41413 EVAP Pressure/Purge Diagnostic Station and the fuel tank cap to the adapter. Turn ON the ignition, with the engine OFF. Command the EVAP vent valve ON (closed) with a scan tool. With the EVAP diagnostic station, pressurize the EVAP system to 13 in. H2O. Rotate the EVAP pressure/purge diagnostic station rotary switch to the OFF/HOLD position. Using the scan tool, compare the Fuel Tank Pressure (FTP) sensor value to the EVAP pressure/purge diagnostic station gage value. Are the EVAP pressure/purge diagnostic station gage and the scan tool FTP sensor values similar? If yes, go to next step. If no, go to step 9 .
5. Monitor the EVAP pressure/purge diagnostic station gage. Command the EVAP canister vent valve OFF or open. Did the EVAP pressure/purge diagnostic station gage drop quickly to near 0 in. H2O? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
6. Command the EVAP vent valve ON and OFF with a scan tool. Do you hear or feel the EVAP vent valve click when commanded ON and OFF? If yes, go to next step. If no, go to step 10 .
7. Turn OFF the ignition. Connect all previously disconnected hardware. With the EVAP pressure/purge diagnostic station, pressurize the EVAP system to 13 in. H2O. Rotate the EVAP pressure/purge diagnostic station rotary switch to the OFF/HOLD position. Disconnect the EVAP vent hose from the EVAP vent valve. Does the scan tool indicate fuel tank pressure near 0 in. H2O? If yes, go to step 14 . If no, go to next step.
8. Disconnect the EVAP vent hose from the EVAP canister. Does the scan tool indicate fuel tank pressure near 0 in. H2O? If yes, go to step 16 . If no, go to step 15 .
9. Is the FTP sensor value more than 4.3 V? If yes, see «DTC P0453: FUEL TANK PRESSURE SENSOR - HIGH VOLTAGE»(ref-132531-S30789581442002012100000) . If no, go to step 12 .
10. Disconnect the EVAP vent valve harness connector. Probe the EVAP vent valve control circuit with a test light connected to battery voltage. Does the test light illuminate? If yes, go to next step. If no, go to step 14 .
11. Test the control circuit of the EVAP vent valve for a short to ground. Did you find and correct the condition? If yes, go to step 19 . If no, go to step 13 .
12. Test for poor connections at the harness connector of the FTP. Did you find and correct the condition? If yes, go to step 19 . If no, go to step 17 .
13. Test for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 19 . If no, go to step 18 .
14. Replace the EVAP vent valve. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 19 .
15. Replace the EVAP canister. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 19 .
16. Repair the blockage in the EVAP vent hose. After repairs, go to step 19 .
17. Replace the FTP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 19 .
18. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
19. Connect all of the EVAP hardware that was previously disconnected. Turn ON the ignition, with the engine OFF. Command the EVAP canister vent valve ON or closed with a scan tool. With the EVAP pressure/purge diagnostic station, pressurize the EVAP system to 13 in. H2O. Rotate the EVAP pressure/purge diagnostic station rotary switch to the OFF/HOLD position. Command the EVAP canister vent valve OFF (open). Is the EVAP pressure/purge diagnostic station value near 0 in. H2O? If yes, go to next step. If no, go to step 3 .
20. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The EVAP system tests run when the engine is first started and meets the Conditions for Running DTC. An intermittent condition could be caused by a damaged EVAP vent housing, a temporary blockage at the EVAP vent valve inlet, or a pinched vent hose. A blockage in the vent system will also cause a poor fuel fill problem. To repair a blockage in the EVAP system, see EVAPORATIVE EMISSION SYSTEM CLEANING in REMOVAL, OVERHAUL & INSTALLATION.

The engine is running.

1. The fuel tank pressure sensor voltage is less than 0.1 volt.
2. All conditions are present for greater than 5 seconds.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test ran and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic ran and passed.
2. The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Idle the engine for 1 minute. Monitor the Diagnostic Trouble Code (DTC) information with a scan tool. Did DTC P1639 fail this ignition cycle? If yes, see «DTC P1639: 5-VOLT REFERENCE B CIRCUIT»(ref-132531-S26177786862002012100000) . If no, go to next step.
3. With the scan tool, observe the Fuel Tank Pressure (FTP) sensor voltage. Does the scan tool indicate that the FTP sensor voltage is less than 0.1 V? If yes, go to step 5 . If no, go to next step.
4. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
5. Turn OFF the ignition. Raise the vehicle. Disconnect the FTP sensor harness connector. Connect a 3-amp fused jumper wire between the 5-volt reference circuit of the FTP sensor and the signal circuit of the FTP sensor. Turn ON the ignition, with the engine OFF. With a scan tool, observe the FTP sensor voltage. Does the scan tool indicate that the FTP sensor voltage is near 5 V? If yes, go to step 8 . If no, go to next step.
6. Test the 5-volt reference circuit of the FTP sensor for a short to ground, high resistance, or an open. Did you find and correct the condition? If yes, go to step 12 . If no, go to next step.
7. Test the signal circuit of the FTP sensor for a short to ground, high resistance, or an open. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 9 .
8. Inspect for poor connections at the harness connector of the FTP sensor. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 10 .
9. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 11 .
10. Replace the FTP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 12 .
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The engine is running.

1. The fuel tank pressure sensor voltage is more than 4.9 volts.
2. All conditions are present for greater than 5 seconds.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test ran and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the MIL during the third consecutive trip in which the diagnostic ran and passed.
2. The History DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Idle the engine for 1 minute. Monitor the diagnostic trouble codes (DTC) information using the scan tool. Did DTC P1635 and P1639 fail this ignition cycle? If yes, see «DTC P1635: 5-VOLT REFERENCE A CIRCUIT»(ref-132531-S10631678312002012100000) and «DTC P1639: 5-VOLT REFERENCE B CIRCUIT»(ref-132531-S26177786862002012100000) . If no, go to next step.
3. Turn ON the ignition, with the engine OFF. With a scan tool, observe the Fuel Tank Pressure (FTP) sensor voltage. Is the FTP sensor voltage more than 4.3 V? If yes, go to step 5 . If no, go to next step.
4. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
5. Turn OFF the ignition. Raise the vehicle. Disconnect the FTP sensor harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the FTP sensor voltage. Does the scan tool indicate that the FTP sensor voltage is greater than 0 V? If yes, go to next step. If no, go to step 7 .
6. Test the signal circuit of the FTP for a short to voltage or short to a 5-volt reference circuit. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 12 .
7. Probe the low reference circuit of the FTP sensor with a test lamp connected to battery voltage. Did the test lamp illuminate? If yes, go to step 9 . If no, go to next step.
8. Test the low reference circuit of the FTP sensor for an open. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 10 .
9. Inspect for poor connections at the FTP sensor harness connector. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 11 .
10. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 13 . If no, go to step 12 .
11. Replace the FTP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 13 .
12. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
13. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
14. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. No MAP sensor DTCs P0105, P0107 or P0108.
2. No TP sensor DTCs P1120 or P1220.
3. No TFP manual valve position switch DTC P1810.
4. The engine vacuum is 0-105 kPa (0-15 psi).
5. The TP angle is 20 to 50 percent.
6. The engine speed is 3,200 to 4,775 RPM.
7. The transmission is not in PARK or NEUTRAL.

The transmission output speed is less than 150 RPM for 3 seconds.

1. The PCM illuminates the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the Conditions for Setting DTC are met.
2. The PCM commands second gear only.
3. The PCM commands maximum line pressure.
4. The PCM inhibits TCC engagement.
5. The PCM freezes shift adapts from being updated.
6. The PCM records the operating conditions when the Conditions for Setting DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
7. The PCM stores DTC P0502 in PCM history during the second consecutive trip in which the Conditions for Setting DTC are met.

1. The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
2. A scan tool can clear the MIL/DTC.
3. The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
4. The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is OFF long enough in order to power down the PCM.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Record the DTC Freeze Frame and Failure Records. Clear the DTC. Raise and support the rear axle assembly. Start the engine. Place the transmission in any drive range. With the drive wheels rotating, does the scan tool Transmission OSS increase with the drive wheel speed? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
3. Turn OFF the ignition. Disconnect the PCM connector C2. Using the Digital Multimeter (DMM) and the J 35616-A GM Terminal Test Kit, measure the resistance between harness connector terminals C2-2 and C2-10. Does the resistance measure 1377-3355 ohms (2WD), or 976-2354 ohms (4WD)? If yes, go to next step. If no, go to step 7 .
4. Place the transmission in NEUTRAL. Select AC volts. Prevent one rear wheel from turning. Rotate the other rear wheel by hand, ensuring that the driveshaft is turning. Does the voltage measure greater than 0.5 V? If yes, go to next step. If no, go to step 12 .
5. Measure the resistance from terminal C2-10 to ground. Does the resistance measure greater than 50 k/ohms? If yes, go to next step. If no, go to step 9 .
6. Reconnect the PCM connector C2. Disconnect the engine wiring harness from the VSS assembly. Turn ON the ignition, with the engine OFF. Test the high circuit (CKT 821) of the VSS assembly for a short to power. Did you find and correct the condition? If yes, go to step 15 . If no, go to step 14 .
7. Disconnect the engine wiring harness from the VSS assembly. Measure the resistance of the VSS assembly. Does the resistance measure 1377-3355 ohms (2WD), or 976-2354 ohms (4WD)? If yes, go to next step. If no, go to step 13 .
8. Was the resistance measured in step 3 greater than 3355 ohms (2WD), or 2354 ohms (4WD)? If yes, go to step 10 . If no, go to step 11 .
9. Test the high circuit (CKT 821) of the VSS assembly for a short to ground. Did you find and correct the condition? If yes, go to step 15 .
10. Test the high circuit (CKT 821) of the VSS assembly for an open. Test the low circuit (CKT 822) of the VSS assembly for an open. Repair as necessary. After repairs, go to step 15 .
11. Test the high circuit (CKT 821) and the low circuit (CKT 822) of the VSS assembly for a short together. Repair as necessary. After repairs, go to step 15 .
12. Remove the VSS assembly. See appropriate AUTOMATIC TRANSMISSION article in TRANSMISSION SERVICING. Inspect the output shaft speed sensor rotor for damage or misalignment. Inspect the case extension bushing for wear. Did you find and correct the condition? If yes, go to step 15 . If no, go to next step.
13. Replace the VSS assembly. After repairs, go to step 15 .
14. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
15. Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Operate the vehicle, so that the transmission output speed is greater than 250 RPM for 2 seconds. Select Specific DTC. Enter DTC P0502. Has the test run and passed? If yes, system is okay. If no, go to step 1 .

1. No TFP manual valve position switch DTC P1810.
2. The engine speed is greater than 450 RPM.
3. The time since the last gear range change is greater than 6 seconds.
4. The time since the last 4WD low state change is greater than 6 seconds.
5. The transmission output speed rise does not exceed 600 RPM within 2 seconds.

1. The transmission output speed drop is greater than 1300 RPM for 3 seconds when the transmission is not in PARK or NEUTRAL.
2. The transmission output speed drop is greater than 8129 RPM for 409 seconds when the transmission is in PARK or NEUTRAL.

1. The PCM illuminates the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the Conditions for Setting DTC are met.
2. The PCM commands a soft landing to second gear.
3. The PCM commands maximum line pressure.
4. The PCM inhibits TCC engagement.
5. The PCM inhibits fourth gear if the transmission is in hot mode.
6. The PCM freezes transmission adapt functions.
7. The PCM records the operating conditions when the Conditions for Setting DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
8. The PCM stores DTC P0503 in PCM history during the second consecutive trip in which the Conditions for Setting DTC are met.

1. The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
2. A scan tool can clear the MIL/DTC.
3. The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
4. The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is OFF long enough in order to power down the PCM.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Record the DTC Freeze Frame and Failure Records. Clear the DTC. Raise and support the rear axle assembly. Start the engine. Place the transmission in D3 range. With the drive wheels rotating, slowly accelerate to 2000 engine RPM and hold. Road test the vehicle if necessary. Does the scan tool Transmission OSS drop or fluctuate more than 1300 RPM? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
3. Turn OFF the ignition. Disconnect the PCM connector C2. Using the Digital Multimeter (DMM) and the J 35616-A GM Terminal Test Kit, measure the resistance between harness connector terminals C2-2 and C2-10. Does the resistance measure 1377-3355 ohms (2WD), or 976-2354 ohms (4WD)? If yes, go to next step. If no, go to step 7 .
4. Place the transmission in NEUTRAL. Select AC volts. Prevent one rear wheel from turning. Rotate the other rear wheel by hand, ensuring that the driveshaft is turning. Does the voltage measure greater than 0.5 V? If yes, go to next step. If no, go to step 12 .
5. Measure the resistance from terminal C2-10 to ground. Does the resistance measure greater than 50 k/ohms? If yes, go to next step. If no, go to step 9 .
6. Reconnect the PCM connector C2. Disconnect the engine wiring harness from the VSS assembly. Turn ON the ignition, with the engine OFF. Test the high circuit (CKT 821) of the VSS assembly for a short to power. Test the low circuit (CKT 822) of the VSS assembly for a short to power. Did you find and correct the condition? If yes, go to step 15 . If no, go to step 14 .
7. Disconnect the engine wiring harness from the VSS assembly. Measure the resistance of the VSS assembly. Does the resistance measure 1377-3355 ohms (2WD), or 976-2354 ohms (4WD)? If yes, go to next step. If no, go to step 13 .
8. Was the resistance measured in Step 3 greater than 3355 ohms (2WD), or 2354 ohms (4WD)? If yes, go to step 10 . If no, go to step 11 .
9. Test the high circuit (CKT 821) of the VSS assembly for a short to ground. Test the low circuit (CKT 822) of the VSS assembly for a short to ground. Repair as necessary. After repairs, go to step 15 .
10. Test the high circuit (CKT 821) of the VSS assembly for an open. Test the low circuit (CKT 822) of the VSS assembly for an open. Repair as necessary. After repairs, go to step 15 .
11. Test the high circuit (CKT 821) and the low circuit (CKT 822) of the VSS assembly for a short together. Repair as necessary. After repairs, go to step 15 .
12. Remove the VSS assembly. See appropriate AUTOMATIC TRANSMISSION article in TRANSMISSION SERVICING. Inspect the output shaft speed sensor rotor for damage or misalignment. Inspect the case extension bushing for wear. Did you find and correct the condition? If yes, go to step 15 . If no, go to next step.
13. Replace the VSS assembly. After repairs, go to step 15 .
14. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
15. Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Operate the vehicle, ensuring that the transmission output speed drop is less than 500 RPM for 2 seconds and output speed is greater than 500 RPM for 2 seconds. Select Specific DTC. Enter DTC P0503. Has the test run and passed? If yes, system is okay, If no, go to step 1 .

Inspect for ABS DTCs. A faulty ABS condition may contribute to setting DTC P0503.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0130, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0442, P0446, P0452, P0453, P0502, P0503, P1120, P1220, P1221, P1512, P1514, P1515, P1516, P1635, P1639 are not set.
2. The engine is operating for at least 2 seconds.
3. The Engine Coolant Temperature (ECT) is more than -40°F (-40°C).
4. The Intake Air Temperature (IAT) is more than -40°F (-40°C).
5. The Barometric (BARO) pressure is more than 65 kPa.
6. The system voltage is between 9-18 volts.
7. The vehicle speed is less than 3 MPH.

1. The actual idle speed is approximately 150 RPM lower than the desired idle speed.
2. The above condition is present for 15 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Start the engine. With a scan tool, command the engine speed up to 1500 RPM, down to 500 RPM, and up to 1500 RPM. Exit the RPM control function. Does the engine speed correspond, within 100 RPM, with each command? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
3. Inspect 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. After repairs, go to next step.
4. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
5. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0130, P0171, P0172, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0442, P0446, P0452, P0453, P0502, P0503, P1120, P1220, P1221, P1512, P1514, P1515, P1516, P1635, P1639 are not set.
2. The engine is operating for at least 2 seconds.
3. The Engine Coolant Temperature (ECT) is more than -40°F (-40°C).
4. The Intake Air Temperature (IAT) is more than -40°F (-40°C).
5. The Barometric (BARO) pressure is more than 65 kPa.
6. The system voltage is between 9-18 volts.
7. The vehicle speed is less than 3 MPH.

1. The actual idle speed is approximately 100 RPM greater than the desired idle speed.
2. The above condition is present for 15 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails. The control module records the operating conditions at the time the diagnostic fails.
2. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Start the engine. Command the engine speed up to 1500 RPM, down to 500 RPM, and up to 1500 RPM with a scan tool. Exit the RPM control function. Does the engine speed correspond, within 100 RPM, with each command? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
3. Inspect for the following conditions: Vacuum leaks. Excessive deposits in the throttle body. A faulty positive crankcase ventilation (PCV) valve. After inspection or repair, go to next step.
4. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
5. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Is DTC P0602 set? If yes, go to next step. If no, go to step 5 .
3. Program the PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. Does DTC P0602 reset? If yes, go to next step. If no, go to step 6 .
4. Ensure that all tool connections are secure. Ensure the programming equipment is operating correctly. Ensure the correct software and the correct calibration is used. Attempt to program the PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. Does DTC P0602 reset? If yes, go to next step. If no, go to step 6 .
5. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
6. Turn ON the ignition, with the engine OFF. Use a scan tool in order to clear DTCs. Turn OFF the ignition for 30 seconds. Start the engine. Does the scan tool display any DTCs? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
7. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

For complete details on programming the PCM, see POWERTRAIN CONTROL MODULE under PROGRAMMING.

1. The system voltage is 8-18 volts.
2. The engine run time is greater than 5 seconds.
3. The vehicle speed is greater than 5 MPH.

The combination of TR switch signals are invalid for 5 seconds. see scheme 42

1. The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM records the operating conditions when the Conditions for Setting DTC are met. The PCM stores this information as Failure Records.
3. The PCM stores DTC P0705 in PCM memory.

Conditions For Clearing DTC

1. A scan tool can clear the DTC.
2. The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
3. The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Select TR Sw. on the scan tool. With the scan tool, observe the TR Sw. display while selecting each transmission range: P, R, N, D3, D2 and D1. Does each selected transmission range match the scan tool TR Sw. display? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, go to next step.
3. Inspect the PNP switch assembly for the following: Damage. Loose or missing mounting hardware. Proper adjustment. Inspect the shift cable for the following: Damaged or stretched cable. Proper adjustment. Did you find and correct a condition? If yes, go to step 16 . If no, go to next step.
4. With the scan tool, observe the TR Sw. A/B/C/P display. Does the scan tool TR Sw. A/B/C/P parameter indicate HI for all range signal states? If yes, go to step 13 . If no, go to next step.
5. Turn OFF the ignition. Disconnect the TR switch 4-way connector. Turn ON the ignition, with the engine OFF. Does the scan tool TR Sw. A/B/C/P parameter indicate HI for all range signal states? If yes, go to next step. If no, go to step 10 .
6. Using the Digital Multimeter (DMM) and the J 35616-A GM Terminal Test Kit, measure the voltage from terminal "A" of the TR switch 4-way connector to ground. Measure the voltage from terminal "B" of the TR switch 4-way connector to ground. Measure the voltage from terminal "C" of the TR switch 4-way connector to ground. Measure the voltage from terminal "D" of the TR switch 4-way connector to ground. Does the voltage measure 10-12 V at all four terminals? If yes, go to next step. If no, go to step 11 .
7. Connect a fused jumper wire from terminal "D" of the TR switch 4-way connector, signal A circuit, to ground while monitoring the scan tool TR Sw. A/B/C/P parameter. When the signal A circuit (CKT 771) is grounded, do any other signal circuits indicate LOW? If yes, go to step 12 . If no, go to next step.
8. Connect a fused jumper wire from terminal "B" of the TR switch 4-way connector, signal B circuit, to ground while monitoring the scan tool TR Sw. A/B/C/P parameter. When the signal B circuit (CKT 772) is grounded, do any other signal circuits indicate LOW? If yes, go to step 12 . If no, go to next step.
9. Connect a fused jumper wire from terminal "C" of the TR switch 4-way connector, signal C circuit, to ground while monitoring the scan tool TR Sw. A/B/C/P parameter. When the signal C circuit (CKT 773) is grounded, do any other signal circuits indicate LOW? If yes, go to step 12 . If no, go to step 14 .
10. Test the signal circuit or circuits (CKTs 771, 772, 773 and 776) of the TR switch that did not indicate HI for a short to ground. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 15 .
11. Test the signal circuit or circuits (CKTs 771, 772, 773 and 776) of the TR switch that did not indicate proper voltage for an open. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 15 .
12. Test the affected signal circuits of the TR switch for a shorted together condition. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 15 .
13. Test the ground circuit (CKT 450) of the TR switch for an open. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
14. Replace the TR switch, this switch is part of the park/neutral position (PNP) switch. See appropriate AUTOMATIC TRANSMISSION article in TRANSMISSION SERVICING. After repairs, go to step 16 .
15. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
16. Perform the following procedures in order to verify the repair: Select DTC. Select Clear Info. Drive the vehicle greater than 5 MPH for a short distance, then stop the vehicle. Select each transmission range: P, R, N, D3, D2 and D1. Place the transmission in PARK. Select Specific DTC. Enter DTC P0705. Has the test run and passed? If yes, system is okay. If no, go to step 1 .

1. No VSS assembly DTCs P0502 or P0503.
2. Brake switch status is open and DTC P0719 has not passed.
3. The ignition is ON.

The PCM detects an open brake switch or circuit, 0 volts, for 15 minutes without changing for 2 seconds, and the following events occur seven times

1. The vehicle speed is less than 5 MPH.
2. Then the vehicle speed is 5-20 MPH for 4 seconds.
3. Then the vehicle speed is greater than 20 MPH for 6 seconds.

1. The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM disregards the brake switch input for TCC scheduling.
3. The PCM freezes transmission adapt functions.
4. The PCM uses throttle position and vehicle speed to determine application and release of the TCC.
5. The PCM records the operating conditions when the Conditions for Setting DTC are met. The PCM stores this information as Failure Records.
6. The PCM stores DTC P0719 in PCM history.

1. A scan tool can clear the DTC.
2. The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
3. The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is OFF long enough in order to power down the PCM.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Record the DTC Failure Records. Clear the DTC. Select TCC Brake Switch on the scan tool. Disconnect the brake switch connector from the brake switch. Connect a test lamp from terminal D of the brake switch connector to ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 4 .
3. Connect a fused jumper wire between terminal C and terminal D of the brake switch connector. Did the TCC Brake Switch status on the scan tool change from Open to Closed? If yes, go to step 7 . If no, go to step 9 .
4. Inspect the ABS fuse for an open. Is the fuse open? If yes, go to next step. If no, go to step 8 .
5. Test the ignition voltage circuit (CKT 584) of the brake switch for a short to ground. Did you find and correct the condition? If yes, go to step 11 . If no, go to next step.
6. Test the signal circuit (CKT 420) of the brake switch for a short to ground. Did you find and correct the condition? If yes, go to step 11 . If no, go to step 10 .
7. Replace the brake switch. See ADJUSTMENTS in appropriate DISC & DRUM article in BRAKES. After repairs, go to step 11 .
8. Repair open in ignition voltage circuit (CKT 584) of the brake switch. After repairs, go to step 11 .
9. Test the signal circuit (CKT 420) of the brake switch for an open. Did you find and correct the condition? If yes, go to step 11 . If no, go to next step.
10. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
11. Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Turn ON the ignition, with the engine OFF. Apply and release the brake pedal. Verify that the scan tool TCC Brake Switch status indicates Closed, 12 volts, for 2 seconds. Select Specific DTC. Enter DTC P0719. Has the test run and passed? If yes, system is okay. If no, go to step 1 .

Inspect for ABS DTCs. A faulty ABS condition may contribute to setting DTC P0719.

1. No VSS assembly DTCs P0502 or P0503.
2. The ignition is ON.

The PCM detects a closed brake switch circuit, 12 volts, without changing for 2 seconds and the following events occur eight times

1. The vehicle speed is greater than 20 MPH for 6 seconds.
2. Then the vehicle speed is between 5-20 MPH for 4 seconds.
3. Then the vehicle speed is less than 5 MPH.

1. The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM records the operating conditions when the Conditions for Setting DTC are met. The PCM stores this information as Failure Records.
3. The PCM stores DTC P0724 in PCM history.

1. A scan tool can clear the DTC.
2. The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
3. The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Install a scan tool. Turn ON the ignition, with the engine OFF. Record the DTC Failure Records. Clear the DTC. Select TCC Brake Switch on the scan tool. Disconnect the brake switch connector from the brake switch. Did the TCC Brake Switch status on the scan tool change from Closed to Open? If yes, go to next step. If no, go to step 4 .
3. Replace the brake switch. See ADJUSTMENTS in appropriate DISC & DRUM article in BRAKES. After repairs, go to step 6 .
4. Test the signal circuit (CKT 420) of the brake switch for a short to power. Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.
5. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
6. Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Turn ON the ignition, with the engine OFF. Apply and release the brake pedal. Verify that the scan tool TCC Brake Switch status indicates Open, 0 volts, for 2 seconds. Select Specific DTC. Enter DTC P0724. Has the test run and passed? If yes, system is okay. If no, go to step 1 .

Inspect for ABS DTCs. A faulty ABS condition may contribute to setting DTC P0724.

1. The ignition switch is in the crank or run position.
2. DTC P1635 is not set.
3. The ignition voltage is greater than 5.23 volts.

TP sensor 1 voltage is less than 0.27 volts or more than 4.67 volts as observed on the scan tool.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM will turn OFF the Malfunction Indicator Lamp (MIL) during the third consecutive trip in which the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. With a scan tool, observe the TP sensor voltage with the accelerator pedal in the rest position. Does the scan tool indicate voltage less than 0.27 V or greater than 4.67 V? If yes, go to step 5 . If no, go to next step.
3. Is DTC P1221 also set? If yes, see «DTC P1221»(ref-132531-S14204156532002012900000) . If no, go to next step.
4. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
5. Turn OFF the ignition. Disconnect the throttle body harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the TP sensor 1 voltage parameter. Does the scan tool indicate voltage at 0 V? If yes, go to next step. If no, go to step 11 .
6. Connect a fused jumper wire between the TP sensor 5-volt reference circuit and the TP sensor signal circuit at the throttle body harness connector. With a scan tool, observe the TP sensor 1 voltage parameter. Does the scan tool indicate the TP sensor 1 voltage at 5 V? If yes, go to next step. If no, go to step 8 .
7. With a test lamp connected to battery voltage, probe the TP sensor low reference circuit. Does the test lamp illuminate? If yes, go to step 17 . If no, go to step 13 .
8. With a Digital Multimeter (DMM), measure the voltage of the TP sensor 1 5-volt reference circuit. Does the DMM indicate voltage at 5 V? If yes, go to step 10 . If no, go to next step.
9. Does the DMM indicate voltage less than 5 V on the TP sensor 1 5-volt reference circuit? If yes, go to step 14 . If no, go to step 16 .
10. Test the TP sensor 1 signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 12 .
11. Test the TP sensor 1 signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
12. Test the TP sensor 1 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
13. Test the TP sensor 1 low reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
14. Test the TP sensor 1 5-volt reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
15. Test the TP sensor 1 5-volt reference circuit for a short to ground. Repair as necessary. After repairs, go to step 21 . If no, go to step 19 .
16. Test the TP sensor 1 5-volt reference circuit for a short to voltage. Repair as necessary. After repairs, go to step 21 .
17. Inspect for poor connections at the throttle body harness connector. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
18. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21 .
19. Inspect for poor connections at the PCM harness connector. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
20. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
21. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
22. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The fuel level sensor is more than 10 percent.
3. The Engine Coolant Temperature (ECT) is more than 158°F (70°C).
4. The engine speed is between 1450-1900 RPM.
5. The engine has been running for more than 200 seconds.
6. The loop status is closed.
7. The Throttle Position (TP) indicated angle is between 25-30 percent.
8. The Evaporative (EVAP) emission purge solenoid command is more than 10 percent.
9. The above conditions have been met for 30 seconds.

The HO2S 1 rich to lean counts is less than 2 or lean to rich counts is less than 2.

1. The Malfunction Indicator Lamp (MIL) will illuminate after 2 consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
3. Inspect and test for the following conditions: Exhaust leak. The HO2S is installed correctly. Damaged wiring. Did you find and correct the condition? If yes, go to step 12 . If no, go to next step.
4. Turn OFF the ignition. Disconnect the HO2S. Turn ON the ignition. Measure the voltage on the HO2S high signal circuit (PCM side). Does the voltage measure near 450 mV? If yes, go to next step. If no, go to step 7 .
5. Jumper the HO2S high signal circuit to the HO2S low signal circuit (PCM side). With a scan tool, observe HO2S voltage parameter. Does the scan tool indicate HO2S voltage at or near 0 mV? If yes, go to step 8 . If no, go to next step.
6. Test the HO2S low signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 10 .
7. Test the HO2S high signal circuit for an open, high resistance, or short to voltage. Did you find and correct the condition? If yes, go to step 12 . If no, go to step 10 .
8. Test for poor connections at the HO2S. Did you find and correct the condition? If yes, go to step 12 . If no, go to next step.
9. Inspect and test for the following conditions: Fuel contamination. Engine oil or coolant consumption. Use of improper RTV sealant. Replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 12 .
10. Test for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 12 . If no, go to next step.
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

DTC P1133 is most likely caused by one of the following conditions

1. The fuel pressure. The system will go rich if fuel pressure is too high. The PCM can compensate for some increase. If the fuel pressure gets too high, a DTC P0172 will be set. See appropriate BASIC DIAGNOSTIC PROCEDURES article.
2. A leaking injector. A leaking or malfunctioning injector can cause the system to go rich.
3. The manifold absolute pressure (MAP) sensor. An output that causes the PCM to sense a higher than normal manifold pressure, indicating a low vacuum, can cause the system to go rich. Disconnecting the MAP sensor will allow the PCM to set a fixed value for the MAP sensor. Substitute a different MAP sensor if the rich condition is gone while the sensor is disconnected.
4. The pressure regulator. Check for a leaking fuel pressure regulator diaphragm by checking for the presence of liquid fuel in the vacuum line to the regulator.
5. The Throttle Position (TP) sensor. An intermittent TP sensor output will cause the system to go rich due to a false indication of the engine accelerating.
6. HO2S 1 contamination. Inspect HO2S 1 for Silicone contamination from fuel or from the use of an incorrect RTV sealant. The sensor may have a white powdery coating. This condition can result in a high but false voltage signal, indicating a rich exhaust. The PCM will then reduce the amount of fuel delivered to the engine, causing a severe surge or driveability problem.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The engine is in power enrichment mode.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is greater than 158°F (70°C).
5. Then engine is operating in Closed Loop.
6. The fuel level sensor is more than 10 percent.
7. The engine run time is more than 10 seconds.

The HO2S 2 remains less than 400 mV for more than 5 seconds. The diagnostic will then run for 11 seconds after a 5 second delay.

1. The Malfunction Indicator Lamp (MIL) will illuminate after 2 consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions when the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running parameters. With a scan tool, observe the HO2S voltage parameter. Does the voltage remain below 400 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S connector. Turn ON the ignition. Does scan tool indicate HO2S 1 voltage less than 400 mV? If yes, go to next step. If no, go to step 7 .
5. Test the HO2S high signal circuit for a short to ground or a short to the HO2S low signal circuit. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
6. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to step 8 .
7. Inspect the vehicle for any of the conditions in Diagnostic Aids. If no problem is found, replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Inspect the exhaust system for the following conditions: Leaks. Corrosion between 3-way catalytic converter and the flange. Loose or missing hardware. Repair any conditions as necessary.
2. A poor electrical connection or a damaged harness. Inspect the harness for a short to ground in the HO2S 2 high signal circuit. Ensure that the HO2S 2 pigtail is not contacting the exhaust. Check for the following conditions: Wiring contacting the exhaust system. Improper mating. Broken locks. Improperly-formed harness connectors. Damaged terminals. Poor terminal-to-wire connections. A damaged harness.
3. Intermittent test. Observe the HO2S 2 on the scan tool while moving any of the related electrical connectors and the wiring harness with the ignition ON. If the malfunction is induced, the HO2S 2 display will change. This procedure should help isolate the location of the malfunction.

An intermittent can be the result of the following conditions

1. A poor electrical connection.
2. Rubbed-through wire insulation.
3. Broken wire inside the insulation.

Obstruction of the air reference and a degrade HO2S 2 performance can result from any attempt to repair the HO2S harness or the connector. The HO2S 2 must have a clean air reference in order for the HO2S 2 to function properly. This clean air reference is obtained by way of the HO2S 2 wires.

1. DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0201, P0202, P0203, P0204, P0205, P0206, P0300, P0336, P0440, P0446, P0452, P0453, P0507, P0601, P0602, P0604, P0606, P1120, P1220, P1221, P1271, P1275, P1280, P1484, P1512, P1514, P1515, P1516, P1621, P1635, P1639, P1680, or P1681 are not set.
2. The engine is in the decel fuel cut-off (DFCO) mode.
3. The ignition 1 signal is more than 10 volts.
4. The Engine Coolant Temperature (ECT) is greater than 158°F (70°C).
5. The fuel level sensor is more than 10 percent.
6. The engine is operating in Closed Loop.
7. The engine run time is more than 10 seconds.

The HO2S 2 remains more than 648 mV for more than 10 seconds. The diagnostic then will run for 11 seconds after a 10 second delay in order to complete 1 test.

1. The Malfunction Indicator Lamp (MIL) will illuminate after 2 consecutive ignition cycles in which the diagnostic runs with the malfunction present.
2. The PCM will record the operating conditions when the diagnostic fails. This information will store in the Freeze Frame/Failure Records buffers.
3. A history DTC stores.

1. The MIL will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.
2. A history DTC will clear after 40 consecutive warm-up cycles without a fault.
3. Use a scan tool in order to clear the DTCs.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Operate the vehicle within the Conditions for Running this DTC. With a scan tool, observe the HO2S voltage parameter. Does the voltage measure above 946 mV? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see appropriate TROUBLE SHOOTING - NO CODES article.
4. Turn OFF the ignition. Disconnect the HO2S connector for the sensor that applies to this DTC. Turn ON the ignition, with the engine OFF. Use the scan tool in order to monitor the HO2S voltage for the sensor that applies to this DTC. Is the HO2S voltage near 447 mV? If yes, go to next step. If no, go to step 6 .
5. The HO2S is detecting a rich exhaust condition or may be contaminated. Check for one of the following conditions: HO2S connector water intrusion. Silicone contaminated HO2S. Fuel contaminated engine oil. Incorrect fuel pressure. A leaking fuel pressure regulator. Rich fuel injectors. Repair any of the above or similar engine conditions as necessary. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 7 .
6. Test the HO2S high signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 9 . If no, go to step 8 .
7. Replace the HO2S. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 9 .
8. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
9. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
10. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Check for the following conditions

1. A rich exhaust. An overly rich exhaust may load the catalyst causing high HO2S 2 signal voltages.
2. Silicone contamination. Silicone contamination of HO2S 2 could cause a false rich condition. A powdery white deposit on the sensor will indicate this condition.

1. DTCs P0122, P0123, P0131, P0132, P0133, or P0134 are not set.
2. The Engine Coolant Temperature (ECT) is more than 70°F (20°C).
3. The engine has been running for longer than 20 seconds.
4. The engine is operating in a Closed Loop operation.
5. The engine is in the power enrichment mode.

The Heated Oxygen Sensor 1 (HO2S) 1 voltage is less than 300 mV for 10 seconds.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The Malfunction Indicator Lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center, if equipped, may display a message.

1. A current DTC Last Test Failed clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Clear the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. Install a scan tool. Are any component related DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC as specified in the supporting test or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S18612385412002012900000) .
4. Check the vehicle for an adequate amount of fuel. Add fuel to the vehicle's fuel tank if the fuel gauge is near empty. Was it necessary to add fuel? If yes, go to step 6 . If no, go to next step.
5. Start the engine. Run the engine at normal operating temperature. Operate the engine above 1200 RPM. With a scan tool, observe the HO2S 1 voltage. Does the scan tool indicate HO2S 1 voltage varying outside 350-550 mV? If yes, diagnose fuel system. See appropriate BASIC DIAGNOSTIC PROCEDURES article. If no, see «DTC P0134: HO2S CIRCUIT - INSUFFICIENT ACTIVITY - SENSOR 1»(ref-132531-S05781289302002012100000) .
6. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
7. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. A restricted fuel filter can supply adequate amounts of fuel at idle, but may not be able to supply enough fuel during heavy acceleration. Water or alcohol in the fuel may cause low HO2S 1 voltage during acceleration.
2. High resistance in the ignition coil control circuits may cause this condition.
3. Manifold absolute pressure (MAP) sensor. High resistance in the MAP sensor circuits may cause this condition.
4. Check for faulty or plugged fuel injectors.

1. The ignition switch in the crank or run position.
2. DTC P1635 is not set.
3. The ignition voltage is more than 5.23 volts.

The TP sensor 2 voltage is less than 0.31 volts or more than 4.7 volts.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails.
3. The control module stores this information in the Freeze Frame and/or the Failure Records. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM will turn OFF the Malfunction Indicator Lamp (MIL) during the third consecutive trip in which the diagnostic runs and passes.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. With a scan tool, observe the TP sensor voltage with the accelerator pedal in the rest position. Does the scan tool indicate voltage less than 0.31 V or greater than 4.7 V? If yes, go to step 4 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
4. Turn OFF the ignition. Disconnect the throttle body harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the TP sensor 2 voltage parameter. Does the scan tool indicate voltage at 5 V? If yes, go to next step. If no, go to step 12 .
5. With a test lamp connected to ground, probe the TP sensor signal circuit. Does the test lamp illuminate? If yes, go to step 12 . If no, go to next step.
6. With a test lamp still connected to the TP sensor signal circuit, observe the TP sensor 2 parameter. Does the scan tool indicate voltage at 0 V? If yes, go to next step. If no, go to step 11 .
7. With a Digital Multimeter (DMM), measure the voltage of the TP sensor 2 5-volt reference circuit. Does the DMM indicate voltage at 5 V. If yes, go to next step. If no, go to step 10 .
8. With a test lamp connected to battery voltage, probe the TP sensor low reference circuit. Does the test lamp illuminate? If yes, go to next step. If no, go to step 14 .
9. Test the TP sensor low reference circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 18 .
10. Does the DMM indicate voltage less than 5 V on the TP sensor 2 5-volt reference circuit? If yes, go to step 15 . If no, go to step 17 .
11. Test the TP sensor 2 signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 13 .
12. Test the TP sensor 2 signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
13. Test the TP sensor 2 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
14. Test the TP sensor 2 low reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
15. Test the TP sensor 2 5-volt reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
16. Test the TP sensor 2 5-volt reference circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
17. Test the TP sensor 2 5-volt reference circuit for a short to voltage. Repair as necessary. After repairs, go to step 22 .
18. Inspect for poor connections at the throttle body harness connector. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
19. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 22 .
20. Inspect for poor connections at the PCM harness connector. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
21. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
22. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
23. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The ignition is ON.
2. DTCs P1120, P1220, P1635, or P1639 are not set.
3. The ignition voltage is greater than 5.23 volts.

The difference between the TP sensor 1 and TP sensor 2 exceeds a predetermined value.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM will turn OFF the Malfunction Indicator Lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Using a scan tool, observe the DTC information. Is DTC P1635 or P1639 also set? If yes, see «DTC P1635: 5-VOLT REFERENCE A CIRCUIT»(ref-132531-S10631678312002012100000) or «DTC P1639: 5-VOLT REFERENCE B CIRCUIT»(ref-132531-S26177786862002012100000) . If no, go to next step.
3. Turn ON the ignition, with the engine OFF. Monitor the TP sensors Agree/Disagree parameter using the scan tool. Does the scan tool indicate Disagree? If yes, go to step 6 . If no, go to next step.
4. Remove the resonator assembly from the throttle body assembly. Remove the ETC fuse. Open the throttle blade to wide open throttle (WOT) by hand and then return it to closed throttle. Stop briefly at approximately 25 percent, 50 percent, 75 percent and 100 percent in each direction. Test the Throttle Sensors Disagree parameter at each stop. Does the scan tool indicate Disagree while rotating the throttle blade? If yes, go to step 6 . If no, go to next step.
5. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
6. Disconnect the TP sensor electrical connector. Turn ON the ignition, with the engine OFF. Measure the voltage between the 5-volt reference circuit of TP sensor 1 and the TP sensor 1 low reference circuit with a Digital Multimeter (DMM). Measure the voltage between the 5-volt reference circuit of TP sensor 2 and the TP sensor 2 low reference circuit with a DMM. Does the DMM display a voltage 4.9-5.1 V for both measurements? If yes, go to step 8 . If no, go to next step.
7. Test the voltage on the 5-volt reference circuit for TP sensor 1 and TP sensor 2 to a battery ground with a DMM. Does the DMM display a voltage 4.9-5.1 V? If yes, go to step 10 . If no, go to step 9 .
8. Observe the TP sensor 1 and TP sensor 2 angle on the scan tool. Does the scan tool indicate both sensors at 100%? If yes, go to step 12 . If no, go to step 11 .
9. Test the 5-volt reference circuit of the TP sensor 1 and TP sensor 2 for high resistance. Did you find and correct the condition? If yes, go to step 15 . If no, go to step 13 .
10. Test the low reference circuit of the TP sensor 1 and TP sensor 2 for high resistance. Did you find and correct the condition? If yes, go to step 15 . If no, go to step 13 .
11. Test the signal circuit of the TP sensor 1 and TP sensor 2 for high resistance. Did you find and correct the condition? If yes, go to step 15 . If no, go to step 13 .
12. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 15 .
13. Test for poor connections and/or terminal tension at the TP sensor and at the PCM. Did you find and correct the condition? If yes, go to step 15 . If no, go to next step.
14. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
15. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
16. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

If DTC is determined to be intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. The battery voltage is more than 5.23 volts.
2. DTCs P1275, P1280, P1635, or P1639 are not set.
3. The accelerator pedal is leaving the idle position.

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and does not fail.
2. A History DTC clears after 40 consecutive warm up cycles in which no failures are reported by this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Using a scan tool, observe the DTC information. Is DTC P1120, P1220, P1275, P1280, P1635, or P1639 also set? If yes, see «DTC P1120: TP SENSOR CIRCUIT»(ref-132531-S41757864772002012100000) , «DTC P1220: THROTTLE POSITION SENSOR 2 - LOW VOLTAGE»(ref-132531-S22027517412002012900000) , «DTC P1275»(ref-132531-S05388258122002012900000) , «DTC P1280»(ref-132531-S17807030072002012900000) , «DTC P1635: 5-VOLT REFERENCE A CIRCUIT»(ref-132531-S10631678312002012100000) or «DTC P1639: 5-VOLT REFERENCE B CIRCUIT»(ref-132531-S26177786862002012100000) . If no, go to next step.
3. Turn OFF the ignition. Disconnect the APP sensor electrical connector. Disconnect the PCM. Use a Digital Multimeter (DMM) to measure the resistance of the following circuits for each of the APP sensors: The low reference circuit. The signal circuit. The 5-volt reference circuit. Did any of the circuits measure more than 5 ohms? If yes, go to step 5 . If no, go to next step.
4. Test for a short between any of the circuits in the APP sensor harness. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 7 . If no, go to step 6 .
5. Repair the high resistance in the circuit. After repairs, go to step 7 .
6. Replace the APP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
7. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
8. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The PCM compares the signal of each of the accelerator pedal position sensor to each other throughout the entire range of operation. Clear the DTCs and actuate the pedal through the entire range with the ignition ON and the engine OFF. Use the J 35616-A Connector Test Adapter Kit for any test that requires probing the PCM harness connector or a component harness connector. Using this kit will prevent damage to the harness connector terminals.

If DTC is determined to be intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. The ignition is ON.
2. The ignition voltage is greater than 5.23 volts.
3. DTC P1635 is not set.

The APP sensor 1 voltage is less than 0.13 volts or more than 4.87 volts.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. With a scan tool observe the APP sensor 1 voltage with the accelerator pedal in the rest position. Does the scan tool indicate voltage less than 0.13 V or greater than 4.87 V? If yes, go to step 5 . If no, go to next step.
3. Is DTC P1271 also set? If yes, see «DTC P1271: EXCESSIVE DIFFERENCE BETWEEN ACCELERATOR PEDAL POSITION SENSORS»(ref-132531-S41607055482002012900000) . If no, go to next step.
4. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
5. Turn OFF the ignition. Disconnect the accelerator pedal harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the APP sensor 1 voltage parameter. Does the scan tool indicate voltage at 0 V? If yes, go to next step. If no, go to step 11 .
6. Connect a fused jumper wire between the APP sensor 1 5-volt reference circuit and the APP sensor 1 signal circuit at the accelerator pedal harness connector. With a scan tool, observe the APP sensor 1 voltage parameter. Does the scan tool indicate the APP sensor 1 voltage at 5 V? If yes, go to next step. If no, go to step 8 .
7. With a test lamp connected to battery voltage, probe the APP sensor low reference circuit. Does the test lamp illuminate? If yes, go to step 17 . If no, go to step 13 .
8. With a Digital Multimeter (DMM), measure the voltage of the APP sensor 1 5-volt reference circuit. Does the DMM indicate voltage at 5 V? If yes, go to step 10 . If no, go to next step.
9. Does the DMM indicate voltage less than 5 V on the APP sensor 1 5-volt reference circuit? If yes, go to step 14 . If no, go to step 16 .
10. Test the APP sensor 1 signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 12 .
11. Test the APP sensor 1 signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
12. Test the APP sensor 1 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
13. Test the APP sensor 1 low reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
14. Test the APP sensor 1 5-volt reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
15. Test the APP sensor 1 5-volt reference circuit for a short to ground. Did you find and correct the condition? If yes, go to step 21 . If no, go to step 19 .
16. Test the APP sensor 1 5-volt reference circuit for a short to voltage. Repair as necessary. After repairs, go to step 21 .
17. Inspect for poor connections at the accelerator pedal harness connector. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
18. Replace the accelerator pedal assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21 .
19. Inspect for poor connections at the PCM harness connector. Did you find and correct the condition? If yes, go to step 21 . If no, go to next step.
20. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
21. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
22. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. The ignition is ON.
2. The ignition voltage is greater than 5.23 volts.
3. DTC P1635 is not set.

The APP sensor 2 voltage is less than 0.13 volts or more than 4.87 volts.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. With a scan tool, observe the APP sensor 2 voltage with the accelerator pedal in the rest position. Does the scan tool indicate voltage less than 0.13 V or greater than 4.87 V? If yes, go to step 5 . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
4. Turn OFF the ignition. Disconnect the accelerator pedal harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the APP sensor 2 voltage parameter. Does the scan tool indicate voltage at 5 V? If yes, go to next step. If no, go to step 12 .
5. With a test lamp connected to ground, probe the APP sensor 2 signal circuit. Does the test lamp illuminate? If yes, go to step 11 . If no, go to next step.
6. With the test lamp still connected to the APP sensor 2 signal circuit, observe the APP sensor 2 parameter. Does the scan tool indicate voltage at 0 V? If yes, go to next step. If no, go to step 11 .
7. With a Digital Multimeter (DMM), measure the voltage of the APP sensor 2 5-volt reference circuit. Does the DMM indicate voltage at 5 V? If yes, go to next step. If no, go to step 10 .
8. With a test lamp connected to battery voltage, probe the APP sensor 2 low reference circuit. Does the test lamp illuminate? If yes, go to next step. If no, go to step 14 .
9. Test the APP sensor low reference circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 18 .
10. Does the DMM indicate voltage less than 5 V on the APP sensor 2 5-volt reference circuit? If yes, go to step 14 . If no, go to step 16 .
11. Test the APP sensor 2 signal circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 13 .
12. Test the APP sensor 2 signal circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
13. Test the APP sensor 2 signal circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
14. Test the APP sensor 2 low reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
15. Test the APP sensor 2 5-volt reference circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
16. Test the APP sensor 2 5-volt reference circuit for a short to ground. Did you find and correct the condition? If yes, go to step 22 . If no, go to step 20 .
17. Test the APP sensor 2 5-volt reference circuit for a short to voltage. Repair as necessary. After repairs, go to step 22 .
18. Inspect for poor connections at the accelerator pedal harness connector. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
19. Replace the accelerator pedal assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 22 .
20. Inspect for poor connections at the PCM harness connector. Did you find and correct the condition? If yes, go to step 22 . If no, go to next step.
21. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
22. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
23. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. DTCs P0013, P0014, P0335, P0336, P0340, P0341, or P1345 are not set.
2. The engine coolant temperature is more than 158°F (70°C).

The crankshaft position system variation values are not stored in the PCM memory.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Clear the MIL and the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Perform the crankshaft position system variation learn procedure. See «CRANKSHAFT POSITION SENSOR»(ref-132531-S34845224152002012100000) under PROGRAMMING. Is the action complete? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S42518896392002012100000) .
3. Clear the DTCs with a scan tool. Turn OFF the ignition. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
4. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The crankshaft position system variation compensating values are stored in PCM memory after a learn procedure has been performed. If the actual crankshaft position variation is not within the crankshaft position system variation compensating values stored in the PCM, DTC P0300 may set.

The crankshaft position system variation learn procedure is also required when the following service procedures have been performed, regardless of whether DTC P1336 is set

1. Engine replacement PCM replacement.
2. A harmonic balancer replacement.
3. Crankshaft replacement.
4. Crankshaft position sensor replacement.
5. Any engine repairs which disturb the crankshaft to crankshaft position sensor relationship.

If the crankshaft position system variation learn procedure cannot be performed successfully, check for the following conditions and correct as necessary

1. A damaged reluctor wheel.
2. Excessive crankshaft runout.
3. A damaged crankshaft.
4. Interference in the signal circuit of the crankshaft position (CKP) sensor.
5. A coolant temperature that is not within the Conditions for Running DTC.
6. The ignition switch is in the ON position until the battery is drained.
7. A PCM power disconnect with the ignition ON may erase the stored value and set the DTC P1336.
8. The ignition switch is in the ON position until the battery is drained.
9. A PCM power disconnect with the ignition ON may erase the stored value and set the DTC P1336.

1. The engine is running.
2. The minimum voltage is 11 volts.

1. The variable cam phaser is commanded to zero.
2. The engine has been running for more than 16 seconds.

1. The PCM will illuminate the Malfunction Indicator Lamp (MIL) during the second consecutive trip in which the diagnostic test has been run and failed.
2. The PCM will store conditions which were present when the DTC set as Freeze Frame/Failure Records data.

1. The PCM will turn OFF the Malfunction Indicator Lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Connect a scan tool. Start the engine. Does the scan tool indicate that DTC P0014 failed this ignition? If yes, see «DTC P0014: CAM PHASER PERFORMANCE»(ref-132531-S28712909762002012100000) . If no, go to next step.
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S36840413272002012100000) .
4. With a scan tool, observe all the Cam Phase Angle parameters. Do all the Cam Phase Angle parameters measure 0°? If yes, see appropriate article in ENGINES. If no, go to next step.
5. Clear the DTCs with a scan tool. Turn OFF the ignition. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
6. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. This code will only set at idle.
2. An improperly torqued harmonic balancer or misbuilt engine.
3. The PCM will disable the ability to command the variable cam phaser on the scan tool. This will prevent engine damage from excessive valve overlap.

1. The engine load is less than 100 percent.
2. The engine speed is less than 6,500 RPM.
3. The vehicle speed is more than 0.6 MPH.
4. A misfire DTC is occurring and requesting the Malfunction Indicator Lamp (MIL) to be illuminated.

The PCM detects an EBCM rough road sensing error.

1. The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM will store the conditions present when the DTC set as Failure Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, see appropriate ANTI-LOCK article in BRAKES. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.

If DTC is determined to be intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. The engine load is less than 60 percent.
2. The engine speed is less than 3200 RPM.
3. The vehicle speed is more than 10 MPH.
4. A misfire DTC is occurring and requesting the MIL to be illuminated.

The PCM is detecting a loss of communication with the EBCM for less than 5 seconds.

1. The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
2. The PCM will store the conditions present when the DTC set as Failure Records data only.

1. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
2. The DTC can be cleared by using the scan tool Clear DTC Information function.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. Select chassis application on the scan tool. Attempt to display anti-lock brake system (ABS) data on the scan tool. Can ABS data be displayed? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM. If no, see appropriate ANTI-LOCK article in BRAKES.

Note. Use the connector test adapter kit J 35616-A for any test that requires probing the following items: The PCM harness connectors. The electrical center fuse/relay cavities. The component terminals. The component harness connector. Using this kit will prevent damage caused by the improper probing of connector terminals.

If DTC is determined to be intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0440, P0442, P0446, P0452, or P0453 are not set.
2. The ignition voltage is between 10-18 volts.
3. The Barometric (BARO) pressure is more than 75 kPa.
4. The fuel level is between 15-85 percent.
5. The Engine Coolant Temperature (ECT) is between 39-86°F (4-30°C).
6. The Intake Air Temperature (IAT) is between 39-86°F (4-30°C).
7. The start up ECT and IAT are within 16°F (9°C) of each other.
8. The Vehicle Speed Sensor (VSS) is less than 75 MPH.

A continuous open purge flow condition is detected during the diagnostic test (fuel tank pressure decreases to less than -11 in. H2O).

1. The PCM will turn the MIL OFF during the first trip in which the diagnostic has been run and passed.
2. The history DTC will clear when the PCM turns OFF the MIL.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Is DTC P0452 or P0453 also set? If yes, see «DTC P0452: FUEL TANK PRESSURE SENSOR - LOW VOLTAGE»(ref-132531-S42569336432002012100000) or «DTC P0453: FUEL TANK PRESSURE SENSOR - HIGH VOLTAGE»(ref-132531-S30789581442002012100000) . If no, go to next step.
3. With a scan tool, seal the EVAP system. Start the engine. Increase the engine idle to 1200-1500 RPM. Observe the FTP sensor with a scan tool. Is the FTP sensor near 0 in. Hg (0 in. H2O)? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S20817002132002012100000) .
4. Turn the ignition OFF. Disconnect the EVAP canister purge valve harness connector. Remove and then install the fuel fill cap. With a scan tool, seal the EVAP system. Start the engine. Increase the engine idle to 1200-1500 RPM. Observe the FTP sensor with a scan tool. Is the FTP sensor near 0 in. Hg (0 in. H2O)? If yes, go to step 7 . If no, go to next step.
5. Turn ON the ignition, with the engine OFF. Connect a test lamp between the control circuit and the ignition voltage circuit of the EVAP purge valve harness connector. Does the test lamp illuminate? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S20817002132002012100000) .
6. Test the purge valve control circuit for a short to ground. Did you find and correct the condition? If yes, go to step 10 . If no, go to step 8 .
7. Replace the EVAP canister purge valve. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 10 .
8. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 10 . If no, go to next step.
9. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
10. Connect all EVAP hardware that was previously disconnected. Use a scan tool to seal the EVAP system. Start the engine and idle at 1200-1500 RPM. Observe the Fuel Tank Pressure (FTP) with a scan tool. Is the fuel tank pressure near 0 in. Hg (0 in. H2O)? If yes, go to next step. If no, go to step 3 .
11. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

1. Carbon release from the EVAP canister could cause the purge valve to stick open intermittently. Check for carbon release in the EVAP system. If carbon is present, see EVAPORATIVE EMISSION SYSTEM CLEANING in REMOVAL, OVERHAUL & INSTALLATION.
2. Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

The ignition is ON.

The difference between the predicted and the actual throttle position is more than a calibrated amount.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and passes.
2. A History DTC clears after 40 consecutive warm-up cycles in which there are no failures reported of this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P1120, P1220, P1221, P1271, P1275 and P1280 also set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Turn OFF the ignition. Inspect the throttle body for the following conditions: A throttle valve that is NOT in the rest position. A throttle valve that is binding open or closed. A throttle valve that is free to move open or closed WITHOUT spring pressure. Did you find any of these conditions with the throttle body? If yes, go to step 15 . If no, go to next step.
4. Disconnect the throttle body harness connector. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 8 . If no, go to next step.
5. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery voltage. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 9 . If no, go to next step.
6. Turn OFF the ignition. Connect the test lamp between the TAC motor control 1 and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then turn OFF? If yes, go to next step. If no, go to step 10 .
7. Turn OFF the ignition. Connect a test lamp between the TAC motor control 2 circuit and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then OFF? If yes, go to step 13 . If no, go to step 10 .
8. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Does the test lamp illuminate? If yes, go to step 11 . If no, go to step 14 .
9. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery voltage. Does the test lamp illuminate? If yes, go to step 12 . If no, go to step 14 .
10. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor controls circuits. Test TAC motor control 1 and 2 circuits for an open or high resistance. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 14 .
11. Repair the short to voltage on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
12. Repair the short to ground on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
13. Test for a poor connection or terminal tension at the throttle body connector. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 15 .
14. Test for a poor connection or terminal tension at the PCM. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 16 .
15. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 17 .
16. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
17. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
18. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 20 percent. This is referred to as the rest position. The throttle valve should not be completely closed nor should they be open any more than the specified amount. The throttle valve should move open and to the closed position without binding under the normal spring pressure. The throttle should NOT be free to move open or closed WITHOUT spring pressure. Replace the throttle body if any of these conditions are found. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

Note. Operating the throttle blade with the Throttle Blade Control function of the scan tool may cause additional DTCs to set. Do not attempt to diagnose DTCs set during this function.

The scan tool has the ability to operate the throttle control system using Special Functions. Actuate the throttle valve using the throttle blade control function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly. Check for the following conditions

1. Use the J 35616-A Connector Test Adapter Kit for any test that requires probing the PCM harness connector or a component harness connector.
2. Poor connections at the PCM or at the component. Inspect the harness connectors for a poor terminal to wire connection. See «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. DTCs P1512, P1515, P1516, P1523, P1635, or P1639 are not set.
2. The engine is running and the engine speed is more than 600 RPM.

The PCM detects that the calculated airflow rate is more than expected.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM will turn OFF the Malfunction Indicator Lamp (MIL) during the third consecutive trip in which the diagnostic has run and passed.
2. The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
3. The DTC can be cleared by using a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are any other DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition. Start the engine. Operate the vehicle within the Conditions for Running 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 cycle? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S20853607312002013000000) .
4. Inspect for the following conditions: Vacuum hoses for splits, kinks, and proper connections as shown on Vehicle Emission Control Information label. Inspect thoroughly for any type of leak or restriction. Air leaks at throttle body mounting area and intake manifold sealing surfaces. Did you find and correct the condition? If yes, go to step 8 . If no, go to next step.
5. Allow the engine to reach operating temperature. Observe the MAP sensor voltage parameter with a scan tool. Is the MAP sensor voltage 0.8-4.0 V? If yes, go to next step. If no, see «DTC P0105: MAP SYSTEM PERFORMANCE»(ref-132531-S33534962272002012100000) .
6. Idle the engine. Observe the MAP sensor kPa parameter with a scan tool. Increase the engine speed slowly and then back to idle. Does the MAP sensor kPa change smoothly and gradually as engine speed is increased and returned to idle? If yes, go to next step. If no, see «DTC P0105: MAP SYSTEM PERFORMANCE»(ref-132531-S33534962272002012100000) .
7. Inspect the throttle body for the following conditions while modulating the throttle through the entire range using the scan tool: Loose or damaged throttle blade. Broken throttle shaft. Drive mechanism damage. If any of these conditions exist, replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Did you find and correct the condition? If yes, go to next step. If no, see «DIAGNOSTIC AIDS»(ref-132531-S20853607312002013000000) .
8. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
9. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

Inspect for the following conditions

1. The throttle blade for damage.
2. A skewed cam sensor signal. Inspect for signals that are intermittently shorted to ground, causing a fluctuating RPM on the scan tool.

If the condition is intermittent, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.

1. The ignition is ON.
2. The ignition voltage is greater than 8 volts.
3. The system is not in battery saver mode.
4. The engine is running.
5. DTC P1514 is not set.

The difference between the predicted and the actual throttle position is more than a calibrated amount.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and passes.
2. A History DTC clears after 40 consecutive warm-up cycles in which there are no failures reported of this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P1120, P1220, P1221, P1271, P1275 and P1280 also set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Turn OFF the ignition. Inspect the throttle body for the following conditions: A throttle valve that is NOT in the rest position. A throttle valve that is binding open or closed. A throttle valve that is free to move open or closed WITHOUT spring pressure. Did you find any of these conditions with the throttle body? If yes, go to step 15 . If no, go to next step.
4. Disconnect the throttle body harness connector. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 8 . If no, go to next step.
5. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery voltage. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 9 . If no, go to next step.
6. Turn OFF the ignition. Connect the test lamp between the TAC motor control 1 and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then turn OFF? If yes, go to next step. If no, go to step 10 .
7. Turn OFF the ignition. Connect a test lamp between the TAC motor control 2 circuit and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then OFF? If yes, go to step 13 . If no, go to step 10 .
8. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Does the test lamp illuminate? If yes, go to step 11 . If no, go to step 14 .
9. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery voltage. Does the test lamp illuminate? If yes, go to step 12 . If no, go to step 14 .
10. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Test the TAC motor control 1 and 2 circuits for an open or high resistance. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 14 .
11. Repair the short to voltage on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
12. Repair the short to ground on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
13. Test for a poor connection or terminal tension at the throttle body connector. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 15 .
14. Test for a poor connection or terminal tension at the PCM. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 16 .
15. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 17 .
16. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
17. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
18. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 20 percent. This is referred to as the rest position. The throttle valve should not be completely closed nor should they be open any more than the specified amount. The throttle valve should move open and to the closed position without binding under the normal spring pressure. The throttle should NOT be free to move open or closed WITHOUT spring pressure. Replace the throttle body if any of these conditions are found. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

Note. Operating the throttle blade with the Throttle Blade Control function of the scan tool may cause additional DTCs to set. Do not attempt to diagnose DTCs set during this function.

The scan tool has the ability to operate the throttle control system using Special Functions. Actuate the throttle valve using the throttle blade control function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly. Check for the following conditions

1. Use the J 35616-A Connector Test Adapter Kit for any test that requires probing the PCM harness connector or a component harness connector.
2. Poor connections at the PCM or at the component. Inspect the harness connectors for a poor terminal to wire connection.
3. If the condition is intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The ignition is ON.
2. The ignition voltage is greater than 8 volts.
3. The system is not in the battery save mode.
4. The engine is running.
5. DTC P1514 is not set.

The difference between the predicted and the actual throttle position is more than a calibrated amount.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) when the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame and/or the Failure Records.
3. The control module commands the TAC system to operate in the Reduced Engine Power mode; or, under certain conditions the control module commands the engine OFF.
4. The message center displays Reduced Engine Power.

1. The PCM turns OFF the MIL after 3 consecutive drive trips that the diagnostic runs and passes.
2. A History DTC clears after 40 consecutive warm-up cycles in which there are no failures reported of this diagnostic or any other emission related diagnostic.
3. The scan tool clears the MIL/DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P1120, P1220, P1221, P1271, P1275, and P1280 also set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Turn OFF the ignition. Inspect the throttle body for the following conditions: A throttle valve that is NOT in the rest position. A throttle valve that is binding open or closed. A throttle valve that is free to move open or closed WITHOUT spring pressure. Did you find any of these conditions with the throttle body? If yes, go to step 14 . If no, go to next step.
4. Disconnect the throttle body harness connector. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 7 . If no, go to next step.
5. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery positive. Did the test lamp illuminate and remain illuminated on either circuit? If yes, go to step 8 . If no, go to next step.
6. Turn OFF the ignition. Connect the test lamp between the TAC motor control 1 and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then turn OFF? If yes, go to next step. If no, go to step 10 .
7. Turn OFF the ignition. Connect a test lamp between the TAC motor control 2 circuit and battery ground. Observe the test lamp as you turn ON the ignition. Does the test lamp flash ON and then OFF? If yes, go to step 13 . If no, go to step 10 .
8. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor controls circuits. Turn ON the ignition, with the engine OFF. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to ground. Does the test lamp illuminate? If yes, go to step 11 . If no, go to step 14 .
9. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Probe the TAC motor control 1 and 2 circuits with the test lamp connected to battery positive. Does the test lamp illuminate? If yes, go to step 12 . If no, go to step 14 .
10. Turn OFF the ignition. Disconnect the PCM connector that contains the TAC motor control circuits. Test the TAC motor control 1 and 2 circuits for an open or high resistance. Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 14 .
11. Repair the short to voltage on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
12. Repair the short to ground on the circuit where the test lamp remained illuminated. After repairs, go to step 17 .
13. Test for a poor connection or terminal tension at the throttle body connector. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 15 .
14. Test for a poor connection or terminal tension at the PCM. Did you find and correct the condition? If yes, go to step 17 . If no, go to step 16 .
15. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 17 .
16. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
17. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
18. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The throttle valve is spring loaded to a slightly open position. The throttle valve should be open approximately 20 percent. This is referred to as the rest position. The throttle valve should not be completely closed nor should they be open any more than the specified amount. The throttle valve should move open and to the closed position without binding under the normal spring pressure. The throttle should NOT be free to move open or closed WITHOUT spring pressure. Replace the throttle body if any of these conditions are found. See appropriate REMOVAL, OVERHAUL & INSTALLATION article.

Note. Operating the throttle blade with the Throttle Blade Control function of the scan tool may cause additional DTCs to set. Do not attempt to diagnose DTCs set during this function.

The scan tool has the ability to operate the throttle control system using Special Functions. Actuate the throttle valve using the throttle blade control function located in the TAC System menu. This function will operate the throttle valve through the entire range in order to determine if the throttle body and system operate correctly. Check for the following conditions

1. Use the J 35616-A Connector Test Adapter Kit for any test that requires probing the PCM harness connector or a component harness connector.
2. Poor connections at the PCM or at the component. Inspect the harness connectors for a poor terminal to wire connection.
3. If the condition is intermittent, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.

1. The ignition is ON and the engine is OFF.
2. The ignition voltage is more than 8.5 volts.
3. Battery Saver Mode is active.

The PCM detects that the commanded and actual throttle positions are not within a calibrated range of each other.

The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.

1. The DTC becomes history when the conditions for setting the DTC are no longer present.
2. The history DTC clears after 40 malfunction free warm-up cycles.
3. The PCM receives a clear code command from the scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are any other DTCs set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Turn OFF the ignition for 15 seconds. Turn ON the ignition, with the engine OFF. Allow the pedal to rest at idle stop for 20 seconds. With a scan tool, observe the indicated throttle position parameter. Does the scan tool indicate throttle position 10.8-23.2%? If yes, go to step 6 . If no, go to next step.
4. Remove the throttle body assembly. Did you find any obstructions preventing the throttle blade from returning to the default position? If yes, go to next step. If no, go to step 6 .
5. Remove the obstruction. After repairs, go to step 7 .
6. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to next step.
7. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
8. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

If you do not find any trouble, inspect for mechanical conditions or binding that may be temperature related. Components may not move freely in extreme heat or cold due to the presence of contaminants or ice formation.

The ignition is ON.

The ignition 1 voltage is present but ignition 0 is not.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The Malfunction Indicator Lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center, if equipped, may display a message.

1. A current DTC Last Test Failed clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Clear the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Are DTCs P0740, P0753, P0785, or P1860 also set? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, go to next step.
3. Test the IGN 0 circuit for an open between the splice and the PCM. Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.
4. Test for poor connections at the PCM connectors. Did you find and correct the condition? If yes, go to step 6 . If no, go to next step.
5. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
6. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
7. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The ignition is ON.

1. The PCM detects a voltage that is higher or lower than required on the 5-volt reference circuit.
2. The above condition is present for longer than 10 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close as possible to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
3. Turn OFF the ignition. Disconnect the throttle body electrical connector. Turn ON the ignition, with the engine OFF. Measure the voltage from the 5-volt reference A circuit of the Throttle Position (TP) sensor 1 to a good ground with a Digital Multimeter (DMM). Is the voltage near 5 V? If yes, go to step 5 . If no, go to next step.
4. Is the voltage more than 5 V? If yes, go to step 8 . If no, go to step 6 .
5. Connect the throttle body electrical connector. Disconnect the AC pressure sensor. Measure the voltage from the 5-volt reference circuit of the AC pressure sensor to a good ground with a DMM. Is the voltage near 5 V? If yes, go to step 10 . If no, go to step 9 .
6. Monitor the DMM while disconnecting all other devices connected to the 5-volt reference A circuit one at a time. If voltage changes when one of the above components are disconnected, replace the component. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Was a component replaced? If yes, go to step 12 . If no, go to next step.
7. Turn OFF the ignition. Disconnect the PCM. Test the 5-volt reference A circuit for a short to ground or for any sensor low reference circuit. If a condition is found, repair as necessary. Did you find and correct a condition? If yes, go to step 12 . If no, go to step 10 .
8. Turn ON the ignition, with the engine OFF. Test the following circuits for a short to voltage: The 5-volt reference A circuit. The FTP sensor signal circuit. If a condition is found, repair as necessary. Did you find and correct a condition? If yes, go to step 12 . If no, go to step 10 .
9. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 12 .
10. Test the 5-volt reference A circuit for a short to the TAC motor control 1 or 2 circuits. Did you find and correct a condition? If yes, go to step 12 . If no, go to next step.
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The ignition is ON.

1. The PCM detects a voltage that is higher or lower than required on the 5-volt reference circuit.
2. The above condition is present for longer than 10 seconds.

1. The control module illuminates the Malfunction Indicator Lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
2. The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records.

1. The control module turns OFF the Malfunction Indicator Lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
2. A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
3. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
4. Use a scan tool in order to clear the MIL and the DTC.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close as possible to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) under SELF-DIAGNOSTIC SYSTEM.
3. Turn OFF the ignition. Disconnect the throttle body electrical connector. Turn ON the ignition, with the engine OFF. Measure the voltage from the 5-volt reference B circuit of the Throttle Position (TP) sensor 2 to a good ground with a Digital Multimeter (DMM). Is the voltage near 5 V? If yes, go to step 5 . If no, go to next step.
4. Is the voltage more than 5 V? If yes, go to step 8 . If no, go to step 6 .
5. Connect the throttle body electrical connector. 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. Is the voltage near 5 V? If yes, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) . If no, go to step 9 .
6. Monitor the DMM while disconnecting all other devices connected to the 5-volt reference B circuit one at a time. If voltage changes when one of the above components are disconnected, replace the component. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Was a component replaced? If yes, go to step 12 . If no, go to next step.
7. Turn OFF the ignition. Disconnect the PCM. Test the 5-volt reference B circuit for a short to ground or for any sensor low reference circuit. If a condition is found, repair as necessary. Did you find and correct a condition? If yes, go to step 12 . If no, go to step 10 .
8. Turn ON the ignition, with the engine OFF. Test the following circuits for a short to voltage: The 5-volt reference B circuit. The MAP sensor signal circuit. If a condition is found, repair as necessary. Did you find and correct a condition? If yes, go to step 12 . If no, go to step 10 .
9. Replace the throttle body assembly. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 12 .
10. Test the 5-volt reference B circuit for a short to the TAC motor control 1 or 2 circuits. Did you find and correct a condition? If yes, go to step 12 . If no, go to next step.
11. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
12. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
13. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.

The ignition is ON.

The ignition 1 voltage is less than 10 volts.

1. The control module stores the DTC information into memory when the diagnostic runs and fails.
2. The Malfunction Indicator Lamp (MIL) will not illuminate.
3. The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
4. The driver information center, if equipped, may display a message.

1. A current DTC Last Test Failed clears when the diagnostic runs and passes.
2. A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
3. Clear the DTC with a scan tool.

1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, see «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-132531-S16910731432002012100000) under SELF-DIAGNOSTIC SYSTEM.
2. Turn ON the ignition, with the engine OFF. With a scan tool, command the throttle blade to 100 percent and back to 0 percent. Exit the throttle blade control function. Did the throttle blade angle follow the commanded angle? If yes, go to next step. If no, go to step 4 .
3. Observe the Freeze Frame/Failure Records data for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see «INTERMITTENT CONDITIONS»(ref-132531-S01351098122002012100000) .
4. With a test lamp connected to ground, probe both sides of the ETC fuse. Does the test lamp illuminate on both sides of the fuse? If yes, go to next step. If no, go to step 6 .
5. With a test lamp connected to ground, probe both sides of the PCM fuse. Does the test lamp illuminate on both sides of the fuse? If yes, go to step 10 . If no, go to step 8 .
6. Test the ETC ignition 1 voltage circuit for a short to ground. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
7. Test the supply voltage to the ETC fuse for an open or high resistance. If a short to ground is found, replace the affected fuse. Did you find and correct the condition? If yes, go to step 16 . If no, go to step 10 .
8. Test the PCM ignition 1 voltage circuit for a short to ground. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
9. Test the supply voltage to the PCM fuse for an open or high resistance. If a short to ground is found, replace the affected fuse. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
10. Disconnect the PCM connector containing the ETC ignition 1 voltage. With a Digital Multimeter (DMM) connected to ground, measure the voltage on the ETC ignition 1 voltage circuit. Does the voltage measure near 12 V? If yes, go to next step. If no, go to step 12 .
11. Disconnect the PCM connector containing the PCM ignition 1 voltage. With a DMM connected to ground, measure the voltage on the PCM ignition 1 voltage circuit. Does the voltage measure near 12 V? If yes, go to step 14 . If no, go to step 13 .
12. Test the ETC ignition 1 voltage circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
13. Test the PCM ignition 1 voltage circuit for an open or high resistance. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
14. Test for poor connections at the PCM connectors. Did you find and correct the condition? If yes, go to step 16 . If no, go to next step.
15. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See «POWERTRAIN CONTROL MODULE»(ref-132531-S15401290812002012100000) under PROGRAMMING. After repairs, go to next step.
16. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2 .
17. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see «DIAGNOSTIC TROUBLE CODE DEFINITIONS»(ref-132531-S07878208602002012100000) . If no, system is okay.