Dtcs P0581 to P0643: Other Jeep Commander I

Monitor Conditions

1. When Monitored: With the ignition key on.

Set Conditions

1. Set Condition: Speed control switch input above the maximum acceptable voltage at the PCM. One trip fault.

Possible Causes

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

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1. 1) ACTIVE DTC Start the engine and allow it to idle for at least 60 seconds. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. NOTE: It may be necessary to test drive the vehicle and operate the speed control in order for this DTC to set. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) SPEED CONTROL SWITCHES Turn the ignition off. Remove and disconnect the Speed Control Switches from the steering wheel. Measure the resistance across each Speed Control Switch. Monitor the ohmmeter while pressing each function button on each switch. The following resistance specs are taken between terminals (V371) S/C Switch No. 1 Signal and (V397) S/C Switch Return circuits of the Switch when holding the switch button in the following position Not pressing any switch - 20.5 kohms On/Off - 0.47 kohms Set - 5.49 kohms Coast - 2.94 kohms Cancel - 1.24 kohms Resume/Accel - 15.4 kohms Does the function on the Speed Control Switches have the correct resistance value? Yes Go to 3) . No Replace the Speed Control Switch that had the incorrect resistance value. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) STEERING COLUMN CONTROL MODULE Disconnect the C1 and C3 SCCM harness connector per Service Information. Measure the resistance of the (V397) Switch Return circuit between the C1 and C3 SCCM harness connectors. Measure the resistance of the (V371) S/C Switch No. 1 Signal circuit between the C1 and C3 SCCM harness connectors. Was the resistance above 5.0 ohms for either circuit? Yes Replace the Steering Column Control Module. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (V371) S/C SWITCH NO. 1 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE Connect the SCCM harness connectors per Service Information. Disconnect the C3 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (V371) S/C Switch No. 1 Signal circuit in the Speed Control harness connector. Is the voltage above 0 volts? Yes Repair the short to battery voltage in the (V371) S/C Switch No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) (V371) S/C SWITCH NO. 1 SIGNAL CIRCUIT OPEN NOTE: The measurement must be taken from both Speed Control Switch harness connectors. Turn the ignition off. Disconnect the C3 SCCM harness connector. Measure the resistance of the (V371) S/C Switch No. 1 Signal circuit from the S/C Switch harness connectors to the C3 SCCM harness connector. Is the resistance below 5.0 ohms? Yes Go to 6) . No Repair the open in the (V371) S/C Switch No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) (V71) S/C SWITCH NO. 1 SIGNAL CIRCUIT OPEN Disconnect the C1 SCCM harness connector CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V71) S/C Switch No. 1 Signal circuit from the C1 SCCM harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms for both measurements? Yes Go to 7) . No Repair the open in the (V71) S/C Switch No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (V397) SWITCH RETURN CIRCUIT OPEN NOTE: The measurement must be taken from both Speed Control Switch harness connectors. Measure the resistance of the (V397) Switch Return circuit from the S/C Switch harness connector to the C3 SCCM harness connector. Is the resistance below 5.0 ohms? Yes Go to 8) . No Repair the open in the (V397) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) (V937) SWITCH RETURN CIRCUIT OPEN Measure the resistance of the (V937) Switch Return circuit from the C1 SCCM harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms for both measurements? Yes Go to 9) . No Repair the open in the (V937) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) SPEED CONTROL SWITCH VOLTAGE VALUES CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 and #8815-1 to perform diagnosis. Using a voltmeter check the voltage on the (V37) S/C Switch No. 1 Signal circuit at the appropriate terminal of the special tool #8815. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. Start the engine and allow it to reach normal operating temperature. Monitor the voltmeter. Allow the engine to idle. With a scan tool, monitor the S/C Switch voltage readings. SWITCH POSITION SWITCH No. 1 VOLTAGE VALUE SWITCH No. 2 VOLTAGE VALUE NO SWITCHES PRESSED 4.31 to 4.78 volts 4.31 to 4.78 volts ON/OFF PRESSED 0.59 to 1.13 volts 3.53 to 3.92 volts RES/ACCEL PRESSED 3.88 to 4.17 volts 2.04 to 2.47 volts SET PRESSED 3.16 to 3.56 volts 1.17 to 1.56 volts COAST PRESSED 2.57 to 2.94 volts 0.77 to 1.09 volts CANCEL PRESSED 1.59 to 1.99 volts 2.84 to 3.25 volts Compare the voltage readings on the voltmeter to what the scan tool displayed. Are the voltage readings out of the listed specification and is there less than a 0.2 of a volt difference between the voltmeter switch values and the scan tool switch value? Yes Replace the Speed Control Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
10. 10) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 384

1. When Monitored: Ignition on and battery voltage greater than 10 volts.

1. Set Condition: An open or shorted condition detected in the Speed control vacuum solenoid control circuit. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

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1. 1) SPEED CONTROL VACUUM CONTROL Ignition on, engine not running. With the scan tool, select View DTCs and record the related Freeze Frame data. With the scan tool, actuate the Speed Control Vacuum Solenoid and note operation. Does the Speed Control Vacuum Solenoid actuate properly? Yes Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure. No Go to 2) .
2. 2) (V30) S/C BRAKE SWITCH OUTPUT CIRCUIT Turn the ignition off. Disconnect the S/C Servo harness connector. Ignition on, engine not running. Using the scan tool, actuate the S/C Vacuum Solenoid. Using a test light connected to ground, probe the (V30) S/C Brake Switch Output circuit in the S/C Servo harness connector. Does the test light illuminate brightly and flash on and off? Yes Go to 5) . No Go to 3) .
3. 3) (V32) S/C SUPPLY CIRCUIT Turn the ignition off. Connect the S/C Servo harness connector. Disconnect the Stop Lamp Switch harness connector. Ignition on, engine not running. Using the scan tool, actuate the S/C Vacuum Solenoid. Using a test light connected to ground, probe the (V32) S/C Supply circuit in the Stop Lamp Switch harness connector. Does the test light illuminate brightly? Yes Go to 4) . No Go to 8) .
4. 4) (Z384) S/C GROUND CIRCUIT OPEN Turn the ignition off. Disconnect the S/C Servo harness connector. Measure the resistance of the (Z384) S/C Ground circuit at the S/C Servo harness connector to ground. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (Z384) S/C Ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) SPEED CONTROL VACUUM SOLENOID Ignition on, engine not running. With the scan tool, actuate the Speed Control Vacuum Solenoid. Using a 12-volt test light connected to battery voltage, probe the (V36) S/C Vacuum Control circuit. Does the test light illuminate brightly and flash on and off? Yes Replace the Speed Control Servo. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (V36) S/C VACUUM SOL CONTROL CIRCUIT OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V36) S/C Vacuum Sol Control circuit from the Speed Control Servo harness connector to the appropriate terminal of special tool # 8815. Is the resistance below 5.0 ohms? Yes Go to 7) . No Repair the open/high resistance in the (V36) S/C Vacuum Sol Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (V36) SPEED CONTROL VACUUM SOLENOID CONTROL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V36) S/C Vacuum Solenoid Control circuit at the Speed Control Servo harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V36) S/C Vacuum Sol Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
8. 8) (V32) S/C SUPPLY OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V32) S/C Supply circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 9) . No Repair the open/high resistance in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) (V32) S/C SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V32) S/C Supply circuit at the Speed Control Servo harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
10. 10) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 393

1. When Monitored: Ignition on.

1. Set Condition: Cruise Switch inputs are not coherent with each other. Example: PCM is reading Switch No. 1 as Accel and Switch No. 2 as Coast at the same time. One trip fault.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

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1. 1) ACTIVE DTC NOTE: This DTC is a two trip fault. If the scan tool indicates a one trip failure, the possible cause may have been the customer pressing both switches simultaneously. Test drive the vehicle and activate the Speed Control system. If the DTC matures to an active fault a repair is necessary. Ask the customer if it is possible that two buttons were pressed at the same time before this DTC set. If this is the case, no repair is necessary. Start the engine. Allow the engine to reach normal operating temperature. With a scan tool, select View DTCs. NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data. Is the DTC Active or Pending at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) SPEED CONTROL ON/OFF SWITCH With the scan tool, monitor the Speed Control Switch voltage. Disconnect the Speed Control On/Off Switch harness connector. Did the voltage change to above 4.8 volts? Yes Replace the Speed Control On/Off Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) SPEED CONTROL RESUME/ACCEL SWITCH With the scan tool, monitor the Speed Control Switch voltage. Disconnect the Speed Control Resume/Accel Switch harness connector. Did the voltage change to above 4.8 volts? Yes Replace the Speed Control Resume/Accel Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) SPEED CONTROL SWITCHES Turn the ignition off. Remove and disconnect the Speed Control Switches from the steering wheel per Service Information. Measure the resistance across each Speed Control Switch. Monitor the ohmmeter while pressing each function button on each switch. The following resistance specs are taken between terminals (V372) S/C Switch No. 2 Signal and (V397) S/C Switch Return circuits of the Switch when holding the switch button in the following position. Not pressing any switch - 20.5 kohms On/Off - 8.87 kohms Set - 0.825 kohms Coast - 0.47 kohms Cancel - 3.92 kohms Resume/Accel - 1.87 kohms The following resistance specs are taken between terminals (V371) S/C Switch No. 1 Signal and (V397) S/C Switch Return circuits of the Switch when holding the switch button in the following position Not pressing any switch - 20.5 kohms On/Off - 0.47 kohms Set - 5.49 kohms Coast - 2.94 kohms Cancel - 1.24 kohms Resume/Accel - 15.4 kohms Does the function on the Speed Control Switches have the correct resistance value? Yes Go to 5) . No Replace the Speed Control Switch that had the incorrect resistance value. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) S/C SWITCH SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE Disconnect the C3 PCM harness connector. Measure the voltage on the (V371) and (V372) S/C Switch Signal circuits at both Speed Control harness connectors. Is the voltage above 5.0 volts? Yes Repair the short to battery voltage in the (V371) or (V372) S/C Switch Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) STEERING COLUMN CONTROL MODULE Turn the ignition off. Disconnect the C1 and C3 SCCM harness connectors per Service Information. Measure the resistance of the (V371/V71) and (V372/V72) S/C Switch Signal circuits between the C1 and C3 SCCM connectors. Measure the resistance of the (V397/V937) Switch Return circuit between the C1 and C3 SCCM harness connectors. Is the resistance above 5.0 ohms for any one of the measurements? Yes Replace the SCCM per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 7) . NOTE: Connect the Steering Column Control Module harness connectors per Service Information before continuing.
7. 7) S/C SWITCH SIGNAL CIRCUIT OPEN CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V371/V71) and (V372/V72) S/C Switch Signal circuits from both Speed Control harness connectors to the appropriate terminals of special tool #8815. Is the resistance below 5.0 ohms for each measurement? Yes Go to 8) . No Repair the excessive resistance in the (V371/V71) or (V372/V72) S/C Switch Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) (V397/V937) SWITCH RETURN CIRCUIT OPEN NOTE: The measurement must be taken from both Speed Control Switch harness connectors. Measure the resistance of the (V397/V937) Switch Return circuit from both Speed Control harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms for both measurements? Yes Go to 9) . No Repair the excessive resistance in the (V397/V937) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) S/C SWITCH SIGNAL CIRCUITS SHORTED TO THE (V397/V937) SWITCH RETURN CIRCUIT Measure the resistance between the (V397) Switch Return circuit and both of the (V371) and (V372) S/C Switch Signal circuits in the S/C Switch harness connector. Is the resistance below 5.0 ohms? Yes Repair the short between the (V397/V937) Switch Return circuit and the (V371/V71) or (V372/V72) S/C Switch Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
10. 10) (V371/V71) S/C SWITCH NO. 1 SIGNAL CIRCUIT SHORTED TO THE (V372/V72) S/C SWITCH NO. 2 SIGNAL CIRCUIT Measure the resistance between the (V371/V71) S/C Switch No. 1 Signal circuit and the (V372/72) S/C Switch No. 2 Signal circuit at both Speed Control harness connectors. Is the resistance below 100 ohms for each circuit? Yes Repair the short between the (V372/V72) S/C Switch No. 2 Signal circuit and the (V371) S/C Switch No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 11) .
11. 11) S/C SWITCH SIGNAL CIRCUITS SHORTED TO GROUND Measure the resistance between ground and the (V371/V71) and (V372/V72) S/C Switch Signal circuits at both S/C Switch harness connectors. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V371/V71) or (V372/V72) S/C Switch Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 12) .
12. 12) SPEED CONTROL SWITCH VOLTAGE VALUES CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 and #8815-1 to perform diagnosis. Using a voltmeter check the voltage on the (V37) S/C Switch No. 1 Signal circuit and the (V38) S/C Switch No. 2 Signal circuit at the appropriate terminals of the special tool #8815. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. Start the engine and allow it to reach normal operating temperature. Monitor the voltmeter. Allow the engine to idle. With a scan tool, monitor the S/C Switch voltage readings. SWITCH POSITION SWITCH No. 1 VOLTAGE VALUE SWITCH No. 2 VOLTAGE VALUE NO SWITCHES PRESSED 4.31 to 4.78 volts 4.31 to 4.78 volts ON/OFF PRESSED 0.59 to 1.13 volts 3.53 to 3.92 volts RES/ACCEL PRESSED 3.88 to 4.17 volts 2.04 to 2.47 volts SET PRESSED 3.16 to 3.56 volts 1.17 to 1.56 volts COAST PRESSED 2.57 to 2.94 volts 0.77 to 1.09 volts CANCEL PRESSED 1.59 to 1.99 volts 2.84 to 3.25 volts Compare the voltage readings on the voltmeter to what the scan tool displayed. Are the voltage readings out of the listed specification and is there less than a 0.2 of a volt difference between the voltmeter switch values and the scan tool switch values? Yes Replace the Speed Control Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 13) .
13. 13) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: Ignition on and battery voltage greater than 10 volts.

1. Set Condition: An open or shorted condition detected in the Speed control vent solenoid control circuit. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

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1. 1) SPEED CONTROL VENT CONTROL Ignition on, engine not running. With the scan tool, select View DTCs and record the related Freeze Frame data. With the scan tool, actuate the Speed Control Vent Solenoid and note operation. Does the Speed Control Vent Solenoid actuate properly? Yes Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure. No Go to 2) .
2. 2) (V30) S/C BRAKE SWITCH OUTPUT CIRCUIT Turn the ignition off. Disconnect the S/C Servo harness connector. Ignition on, engine not running. Using the scan tool, actuate the S/C Vent Solenoid. Using a test light connected to ground, probe the (V30) S/C Brake Switch Output circuit in the S/C Servo harness connector. Does the test light illuminate brightly and flash on and off? Yes Go to 5) . No Go to 3) .
3. 3) (V32) S/C SUPPLY CIRCUIT Turn the ignition off. Connect the S/C Servo harness connector. Disconnect the Stop Lamp Switch harness connector. Ignition on, engine not running. Using the scan tool, actuate the S/C Vent Solenoid. Using a test light connected to ground, probe the (V32) S/C Supply circuit in the Stop Lamp Switch harness connector. Does the test light illuminate brightly? Yes Go to 4) . No Go to 8) .
4. 4) (Z384) S/C GROUND CIRCUIT OPEN Turn the ignition off. Disconnect the S/C Servo harness connector. Measure the resistance of the (Z384) S/C Ground circuit at the S/C Servo harness connector to ground. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (Z384) S/C Ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) SPEED CONTROL VENT SOLENOID Ignition on, engine not running. With the scan tool, actuate the Speed Control Vent Solenoid. Using a 12-volt test light connected to battery voltage, probe the (V36) S/C Vent Control circuit. Does the test light illuminate brightly and flash on and off? Yes Replace the Speed Control Servo. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (V35) S/C VENT CONTROL CIRCUIT OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V35) S/C Vent Sol Control circuit from the Speed Control Servo harness connector to the appropriate terminal of special tool # 8815. Is the resistance below 5.0 ohms? Yes Go to 7) . No Repair the open/high resistance in the (V35) S/C Vent Sol Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (V35) SPEED CONTROL VENT SOLENOID CONTROL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V35) S/C Vent Solenoid Control circuit at the Speed Control Servo harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V35) S/C Vent Sol Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
8. 8) (V32) S/C SUPPLY OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V32) S/C Supply circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 9) . No Repair the open/high resistance in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) (V32) S/C SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V32) S/C Supply circuit at the Speed Control Servo harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
10. 10) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: With the ignition key on.

1. Set Condition: Cruise switch voltage output is not out of range but it does not equal any of the values for any of the button positions. One trip fault.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

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1. 1) ACTIVE DTC Start the engine and allow it to idle for at least 60 seconds. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. NOTE: It may be necessary to test drive the vehicle and operate the speed control in order for this DTC to set. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) SPEED CONTROL SWITCHES Turn the ignition off. Remove the Speed Control Switches from the steering wheel. Measure the resistance across each Speed Control Switch. Monitor the ohmmeter while pressing each function button on each switch. The following resistance specs are taken between terminals (V372) S/C Switch No. 2 Signal and (V397) S/C Switch Return circuits of the Switch when holding the switch button in the following position. Not pressing any switch - 20.5 kohms On/Off - 8.87 kohms Set - 0.825 kohms Coast - 0.47 kohms Cancel - 3.92 kohms Resume/Accel - 1.87 kohms The following resistance specs are taken between terminals (V371) S/C Switch No. 1 Signal and (V397) S/C Switch Return circuits of the Switch when holding the switch button in the following position Not pressing any switch - 20.5 kohms On/Off - 0.47 kohms Set - 5.49 kohms Coast - 2.94 kohms Cancel - 1.24 kohms Resume/Accel - 15.4 kohms Does the function on the Speed Control Switches have the correct resistance value? Yes Go to 3) . No Replace the Speed Control Switch that had the incorrect resistance value. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) (V372) S/C SWITCH NO. 2 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE Disconnect the C3 PCM harness connector. Disconnect the C3 Steering Column Control Module harness connector. Ignition on, engine not running. Measure the voltage of the (V372) S/C Switch No. 2 Signal circuit in the S/C Switch harness connectors. Is the voltage above 0 volts? Yes Repair the short to battery voltage in the (V372) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (V72) S/C SWITCH NO. 2 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE Disconnect the C1 Steering Column Control Module harness connector per Service Information. Ignition on, engine not running. Measure the voltage on the (V72) S/C Switch No. 2 Signal circuit in the C1 SCCM harness connector. Is the voltage above 0 volts? Yes Repair the short to battery voltage in the (V72) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) STEERING COLUMN CONTROL MODULE Turn the ignition off. Measure the resistance of the (V372) S/C Switch No. 2 Signal circuit between the C1 and C3 SCCM connections. Measure the resistance of the (V397) Switch Return circuit between the C1 and C3 SCCM connections. Is the resistance above 5.0 ohms? Yes Replace the Steering Column Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (V372) S/C SWITCH NO. 2 SIGNAL CIRCUIT OPEN NOTE: The measurement must be taken from both Speed Control Switch harness connectors. Measure the resistance of the (V372) S/C Switch No. 2 Signal circuit from both Speed Control harness connectors to the C3 SCCM harness connector. Is the resistance below 5.0 ohms for both measurements? Yes Go to 7) . No Repair the open in the (V372) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (V72) S/C SWITCH NO. 2 SIGNAL CIRCUIT OPEN CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V72) S/C Switch No. 2 Signal circuit from the C1 SCCM harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms for both measurements? Yes Go to 8) . No Repair the open in the (V72) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) (V397) SWITCH RETURN CIRCUIT OPEN Measure the resistance of the (V397) Switch Return circuit from the S/C Switch harness connectors to the C3 SCCM harness connector. Is the resistance below 5.0 ohms for both measurements? Yes Go to 9) . No Repair the open in the (V397) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) (V937) SWITCH RETURN OPEN Measure the resistance of the (V397) Switch Return circuit from the C1 SCCM harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms for both measurement? Yes Go to 10) . No Repair the open in the (V937) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
10. 10) (V372) S/C SWITCH NO. 2 SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V372) S/C Switch No. 2 Signal circuit in the Speed Control harness connectors. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V372) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 11) .
11. 11) (V72) S/C NO. 2 SWITCH SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V72) S/C Switch No. 2 Signal circuit in the C1 SCCM harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V72) S/C Switch No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 12) .
12. 12) (V372) S/C SWITCH NO. 2 SIGNAL CIRCUIT SHORTED TO THE (V397) SWITCH RETURN CIRCUIT Measure the resistance between the (V372) S/C Switch No. 2 Signal circuit and the (V397) Switch Return circuit in the Speed Control harness connector. Is the resistance below 5.0 ohms? Yes Repair the short between the (V372) S/C Switch No. 2 Signal circuit and the (V397) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 13) .
13. 13) (V72) S/C SWITCH NO. 2 SIGNAL CIRCUIT SHORTED TO THE (V937) S/C SWITCH RETURN CIRCUIT Measure the resistance between the (V72) S/C Switch No. 2 Signal circuit and the (V937) S/C Switch Return circuit in the C1 SCCM harness connector. Is the resistance below 5.0 ohms? Yes Repair the short between the (V72) S/C Switch No. 2 Signal circuit and the (V937) Switch Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 14) .
14. 14) SPEED CONTROL SWITCH VOLTAGE VALUES CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 and #8815-1 to perform diagnosis. Using a voltmeter check the voltage on the (V37) S/C Switch No. 1 Signal circuit and the (V38) S/C Switch No. 2 Signal circuit at the appropriate terminals of the special tool #8815. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. Start the engine and allow it to reach normal operating temperature. Monitor the voltmeter. Allow the engine to idle. With a scan tool, monitor the S/C Switch voltage readings. SWITCH POSITION SWITCH No. 1 VOLTAGE VALUE SWITCH No. 2 VOLTAGE VALUE NO SWITCHES PRESSED 4.31 to 4.78 volts 4.31 to 4.78 volts ON/OFF PRESSED 0.59 to 1.13 volts 3.53 to 3.92 volts RES/ACCEL PRESSED 3.88 to 4.17 volts 2.04 to 2.47 volts SET PRESSED 3.16 to 3.56 volts 1.17 to 1.56 volts COAST PRESSED 2.57 to 2.94 volts 0.77 to 1.09 volts CANCEL PRESSED 1.59 to 1.99 volts 2.84 to 3.25 volts Compare the voltage readings on the voltmeter to what the scan tool displayed. Are the voltage readings out of the listed specification and is there less than a 0.2 of a volt difference between the voltmeter switch values and the scan tool switch values? Yes Replace the Speed Control Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 15) .
15. 15) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: With the ignition key on.

1. Set Condition: Speed control switch input No. 2 is below the minimum acceptable voltage at the PCM. One trip fault.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: With the ignition key on.

1. Set Condition: Speed Control Switch No. 2 input above the maximum acceptable voltage at the PCM. One trip fault.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: With the ignition key on. The speed control switched on.

1. Set Condition: The speed control power supply circuit is either open or shorted to ground for more than 2.6 seconds. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Scheme 411

Scheme 412

1. 1) ACTIVE DTC NOTE: If this code is setting on a vehicle that doesn't have a S/C Servo, flash the correct code into the PCM or the wrong PCM may have previously been installed. Ignition on, engine not running. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) (V32) S/C SUPPLY CIRCUIT Turn the ignition off. Disconnect the Stop Lamp Switch harness connector. Ignition on, engine not running. (It may be necessary to start the engine.) Using a 12-volt test light connected to ground, probe the (V32) S/C Supply circuit in the Switch harness connector while holding the Cruise Switch in the ON position. Does the test light illuminate brightly? Yes Go to 3) . No Go to 7) .
3. 3) STOP LAMP SWITCH Disconnect and remove the Stop Lamp Switch. Measure the resistance across the (V32) S/C Supply circuit terminal and the (V30) S/C Brake Switch Output circuit terminal in the Stop Lamp Switch. Push the Plunger of the Switch in and let it out. Does the resistance change from below 5.0 ohms to an open circuit? Yes Go to 4) . No Replace the Stop Lamp Switch. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (V30) S/C BRAKE SWITCH OUTPUT Turn the ignition off. Connect the Stop Lamp Switch harness connector and install the Switch. Disconnect the Speed Control Servo harness connector. Ignition on, engine not running. NOTE: It is necessary to PRESS and HOLD the Speed Control Switch in the ON position while checking for voltage. Using a 12-volt test light connected to ground, probe the (V30) S/C Brake Switch Output circuit in the Servo Harness connector. Does the test light illuminate brightly? Yes Replace the S/C Servo. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) (V30) S/C BRAKE SWITCH OUTPUT CIRCUIT OPEN Turn the ignition off. Disconnect the Brake Lamp Switch harness connector. Measure the resistance of the (V30) S/C Brake Switch Output circuit from the Stop Lamp Switch harness connector to the S/C Servo harness connector. Is the resistance below 5.0 ohms? Yes Repair the excessive resistance in the (V30) S/C Brake Switch Output circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (V30) S/C BRAKE SWITCH OUTPUT CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V30) S/C Brake Switch Output circuit in the Speed Control Servo harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V30) S/C Brake Switch Output circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
7. 7) (V32) S/C SUPPLY CIRCUIT OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (V32) S/C Supply circuit from the Stop Lamp Switch harness connector to the appropriate terminal of special tool #8815. Is the resistance above 5.0 ohms? Yes Repair the open in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (V32) S/C SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (V32) S/C Supply circuit in the Stop Lamp Switch harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (V32) S/C Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
9. 9) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: With the ignition on.

1. Set Condition: Internal Bus communication failure between processors. One Trip Fault. Three Global Good Trips to Clear.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: With the ignition on.

1. Set Condition: Internal checksum for software failed, does not match calculated value. One Trip Fault, Three Good Trips to clear.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Engine running.

1. Set Condition: When the PCM recognizes an internal failure to communicate with the ECM or the CMP and CKP Sensor count periods are too short. One trip fault. ETC light is flashing.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: When the Throttle Motor is powered.

1. Set Condition: When A2D reading does not return to ground within a set period of time of test activation, this fault sets. The test typically runs a couple of times per second, and is the reason why APP2 signal spikes to ground a couple of times per second in normal running. Reprogramming the module may not always fix this fault. One trip fault. ETC lamp is illuminated.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Throttle motor is powered and no matured faults related to APP Sensors.

1. Set Condition: When secondary software determines that APPS 1 and APPS 2 signals do not match for a period of time. One trip fault. ETC lamp will flash

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Throttle motor is powered and no matured faults related to TP Sensors.

1. Set Condition: When secondary software determines that TPS 1 and TPS 2 signals do not match for a period of time. One trip fault. ETC lamp will flash.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Throttle motor is powered and no matured faults related to the Engine Coolant Temp Sensor.

1. Set Condition: When secondary software determines that the Coolant Temperature is implausible for a period of time. One trip fault. ETC lamp will flash.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Throttle motor is powered.

1. Set Condition: When secondary software determines that the customer requested output is not being achieved by the engine for a period of time. One trip fault. ETC lamp will flash.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Throttle motor is powered and no camshaft or crankshaft electrical signal related DTCs are set.

1. Set Condition: When secondary software determines that the engine speed is implausible for a period of time. One trip fault. ETC lamp will flash.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: With the ignition on. Engine running.

1. Set Condition: When the PCM tries to regulate the generator field with no result during monitoring. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Scheme 413

Scheme 414

Scheme 415

Scheme 416

1. 1) ACTIVE DTC Start the engine and allow it to reach operating temperature. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death. Increase engine speed by pressing the accelerator pedal. Do not exceed 3500 RPM. With the scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) GENERATOR OPERATION Turn the ignition off. Disconnect the Generator harness connector. Using a 12-volt test light connected to ground, probe the (K125) Generator Field Control circuit in the Generator Field harness connector. Ignition on, engine not running. NOTE: The DTC needs to be cleared before actuating the Solenoid, if the DTC is not cleared, the Solenoid may not be allowed to actuate. With a scan tool, actuate the Generator Field Driver. NOTE: The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery. Does the test light illuminate brightly and flash on and off? Yes Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors. If OK, replace the Generator. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K125) GEN FIELD CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (K125) Gen Field Control circuit in the Generator Field harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K125) Gen Field Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (K125) GEN FIELD CIRCUIT OPEN Turn the ignition off. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (K125) Gen Field Control circuit from the Generator Field harness connector to appropriate terminal of the special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (K125) Gen Field Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K125) GEN FIELD CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K125) Gen Field Control circuit in the Generator Field harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K125) Gen Field Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM). Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 417

1. When Monitored: With the ignition on. Battery voltage greater than 10.4 volts and the ASD sense switch is on.

1. Set Condition: Actual Fuel Pump Relay state is not equal to desired state. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Scheme 418

Scheme 419

Scheme 420

Scheme 421

1. 1) FUEL PUMP RELAY OPERATION Ignition on, engine not running. With a scan tool, actuate the Fuel Pump Relay. Is the Fuel Pump Relay operating? Yes Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure. No Go to 2) .
2. 2) FUEL PUMP RELAY Turn the ignition off. Remove the Fuel Pump Relay from the IPM. Measure the resistance of the Fuel Pump Relay Coil. Is the resistance between 70 to 90 ohms? Yes Go to 3) . No Verify that there is good pin to terminal contact in the Fuel Pump Module, Relay, and Powertrain Control Module connectors. If OK, replace the Fuel Pump Relay. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) (A916) FUSED B+ CIRCUIT Using a 12-volt test light connected to ground, probe the (A916) Fused B+ circuit. Does the test light illuminate brightly? Yes Go to 4) . No Repair the open or short to ground in the (A916) Fused B+ circuit. Inspect the related fuse and repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (F942) FUSED IGNITION SWITCH OUTPUT CIRCUIT Ignition on, engine not running. Using a 12-volt test light connected to ground, probe the (F942) Fused Ignition Switch Output circuit. Does the test light illuminate brightly? Yes Go to 5) . No Repair the open or short to ground in the (F942) Fused Ignition Switch Output circuit. Inspect the related fuse and repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K31) FUEL PUMP RELAY CONTROL CIRCUIT OPEN Turn the ignition off. Disconnect the C3 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (K31) Fuel Pump Relay Control circuit from the IPM to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 6) . No Repair the open in the (K31) Fuel Pump Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) (K31) FUEL PUMP RELAY CONTROL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K31) Fuel Pump Relay Control circuit in the IPM. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K31) Fuel Pump Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 7) .
7. 7) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the Powertrain Control Module. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Fuel Pump Module and Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: Throttle motor is powered and no vehicle speed related DTCs have matured.

1. Set Condition: When secondary software determines that the vehicle speed is implausible for a period of time. One trip fault. ETC lamp will flash.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: At initialization.

1. Set Condition: The VIN has not been programmed into the PCM. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Ignition on.

1. Set Condition: Odometer is not programed into the PCM. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: Ignition on.

1. Set Condition: The Secret Key information has not been programmed into the PCM. One Trip Fault. Three good trips to turn off the MIL.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

1. When Monitored: The engine running. The engine speed greater than 1157 RPM.

1. Set Condition: The PCM recognizes the alternator output voltage is less than the Battery feed circuit voltage. One trip failure. The Generator light will illuminate. The fault will be checked again on the next key cycle.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Scheme 422

Scheme 423

1. 1) ACTIVE DTC NOTE: Inspect the vehicle for aftermarket accessories that may exceed the Generator System output. NOTE: The battery must be fully charged. NOTE: The Generator belt tension and condition must be checked before continuing. Ignition on, engine not running. With a scan tool, select View DTCs. Start the engine. Allow the idle to stabilize. With the scan tool, View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) EXCESSIVE RESISTANCE IN THE (A803) GENERATOR SENSE CIRCUIT Turn the ignition off. Disconnect the Generator harness connector. Disconnect the C1 PCM harness connector. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis. Measure the resistance of the (A803) Generator Sense circuit from the Generator harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 3) . No Repair the excessive resistance in the (A803) Generator Sense circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) (A803) GENERATOR SENSE CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (A803) Generator Sense circuit at the Generator harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (A803) Generator Sense circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) GENERATOR OPERATION Connect the C1 PCM harness connector. Ignition on, engine not running. NOTE: The DTC needs to be cleared before actuating the Solenoid, if the DTC is not cleared, the Solenoid may not be allowed to actuate. Using a 12-volt test light connected to ground, probe the (K20) Generator Field Control circuit in the Generator Field harness connector. With a scan tool, actuate the Generator Field Driver. NOTE: The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows 100% actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 25% actuation, the brightness should be 25% as bright as a direct connection to the battery. Does the test light illuminate brightly and flash on and off? Yes Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors. If OK, replace the Generator. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM). Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 424

1. When Monitored: Ignition on.

1. Set Condition: When the PCM recognizes the Primary 5-volt Supply circuit voltage is too low. One Trip Fault. ETC light is flashing.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Scheme 425

Scheme 426

1. 1) ACTIVE DTC Ignition on, engine not running. With a scan tool, select View DTCs. NOTE: Improperly installed aftermarket accessories can cause this DTC to set. Check for wiring added by customer. Is the DTC Active at this time? Yes Go to 2) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
2. 2) (F855) PRIMARY 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C2 PCM harness connector. Disconnect all the Sensors that share the (F855) Primary 5-volt Supply circuit. Measure the resistance between ground and the (F855) Primary 5-volt Supply circuit in the CKP Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (F855) Primary 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) 5-VOLT SENSOR Turn the ignition off. Reconnect all the previously disconnected Sensors except for the CKP Sensor harness connector. Ignition on, engine not running. Measure the voltage on the (F855) Primary 5-volt Supply circuit in the CKP Sensor harness connector. Is the voltage below 4.5 volts? Yes Go to 4) . No Replace the CKP Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) 5-VOLT SENSOR SHORTED TO GROUND Measure the voltage on the (F855) Primary 5-volt Supply circuit at the CKP Sensor harness connector. NOTE: You must Turn the Ignition OFF when disconnecting any of the Sensor harness connectors and Turn the Ignition On to check the voltage readings. While monitoring the voltage, disconnect each Sensor harness connector that shares the (F855) Primary 5-volt Supply circuit, one at a time. NOTE: Reconnect all the Sensors and clear all trouble codes before continuing. Does the voltage increase above 4.5 volts when disconnecting any of the remaining Sensors? Yes Replace the Sensor that causes the (F855) Primary 5-volt Supply circuit voltage to increase when disconnected. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) PCM NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits. Were there any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: Ignition on.

1. Set Condition: When the PCM recognizes the Primary 5-volt Supply circuit voltage is too high. One Trip Fault. ETC light is flashing.

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .