Dtcs P0325 to P0501: Other Jeep Commander I

Monitor Conditions

1. When Monitored: This monitor runs above 2000 RPM, under open throttle conditions. The Knock diagnostic does not run at idle or during decelerations. The high voltage test runs all the times the engine is running.

Set Conditions

1. Set Condition: The High voltage fault will set at 4.8 volts. Two Trip Fault. Three good trips to turn off the MIL.

Possible Causes

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

Scheme 237

Scheme 238

Scheme 239

Scheme 240

Scheme 241

1. 1) ACTIVE DTC 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) (K42) KNOCK SENSOR NO. 1 SIGNAL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the Knock Sensor harness connector. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (K42) Knock Sensor No. 1 Signal circuit in the Knock Sensor harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K42) Knock Sensor No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K42) KNOCK SENSOR NO. 1 SIGNAL 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 (K42) Knock Sensor No. 1 Signal circuit from the Knock Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 4) . No Repair the open in the (K42) Knock Sensor No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (K942) KNOCK SENSOR NO. 1 RETURN CIRCUIT OPEN Measure the resistance of the (K942) Knock Sensor No. 1 Return circuit from the Knock Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (K942) Knock Sensor No. 1 Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K42) KNOCK SENSOR NO. 1 SIGNAL CIRCUIT SHORTED TO THE (K942) KNOCK SENSOR NO. 1 RETURN CIRCUIT Measure the resistance between the (K42) Knock Sensor No. 1 Signal circuit and the (K942) Knock Sensor No. 1 Return circuit in the Knock Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short between the (K42) Knock Sensor No. 1 Signal circuit and the (K942) Knock Sensor No. 1 Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (K42) KNOCK SENSOR NO. 1 SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K42) Knock Sensor No. 1 Signal circuit in the Knock Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K42) Knock Sensor No. 1 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 7) .
7. 7) KNOCK SENSOR 1 Turn the ignition off. Replace the Knock Sensor 1. Connect the Powertrain Control Module (PCM) connector. Turn the ignition on. With the scan tool, clear DTCs. Start the engine and allow it to reach normal 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. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to reset. With the scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 8) . No Test complete. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Knock Sensor 1 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. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: This monitor runs above 2000 RPM, under open throttle conditions. The Knock diagnostic does not run at idle or during decelerations. The high voltage test runs all the times the engine is running.

1. Set Condition: The High voltage fault will set at 4.8 volts. Two 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 242

Scheme 243

Scheme 244

Scheme 245

Scheme 246

1. 1) ACTIVE DTC 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) (K242) KNOCK SENSOR NO. 2 SIGNAL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the No. 2 Knock Sensor harness connector. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (K242) Knock Sensor No. 2 Signal circuit in the Knock Sensor harness connector. Is there any voltage present? Yes Repair the short to battery voltage in the (K242) Knock Sensor No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K242) KNOCK SENSOR NO. 2 SIGNAL 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 (K242) Knock Sensor No. 2 Signal circuit from the Knock Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 4) . No Repair the open in the (K242) Knock Sensor No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (K924) KNOCK SENSOR NO. 2 RETURN CIRCUIT OPEN Measure the resistance of the (K924) Knock Sensor No. 2 Return circuit from the Knock Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (K924) Knock Sensor No. 2 Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K242) KNOCK SENSOR NO. 2 SIGNAL CIRCUIT SHORTED TO THE (K924) KNOCK SENSOR NO. 2 RETURN CIRCUIT Measure the resistance between the (K242) Knock Sensor No. 2 Signal circuit and the (K924) Knock Sensor No. 2 Return circuit in the Knock Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short between the (K242) Knock Sensor No. 2 Signal circuit and the (K924) Knock Sensor No. 2 Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (K242) KNOCK SENSOR NO. 2 SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K242) Knock Sensor No. 2 Signal circuit in the Knock Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K242) Knock Sensor No. 2 Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 7) .
7. 7) KNOCK SENSOR 2 Turn the ignition off. Replace the Knock Sensor 2. Connect the Powertrain Control Module (PCM) connector. Turn the ignition on. With the scan tool, clear DTCs. Start the engine and allow it to reach normal 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. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to reset. With the scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 8) . No Test complete. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Knock Sensor 2 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. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 247

1. When Monitored: Engine cranking.

1. Set Condition: No CKP signal is present during engine cranking, and at least 8 camshaft position sensor signals have occurred. 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 248

Scheme 249

Scheme 250

Scheme 251

Scheme 252

Scheme 253

Scheme 254

Scheme 255

1. 1) ACTIVE DTC Crank the engine. Ignition on, engine not running. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Go to 14) .
2. 2) (F855) 5-VOLT SUPPLY CIRCUIT Turn the ignition off. Disconnect the CKP Sensor harness connector. Ignition on, engine not running. Measure the voltage on the (F855) 5-volt Supply circuit in the CKP Sensor harness connector. Is the voltage between 4.5 and 5.2 volts? Yes Go to 3) . No Go to 10) .
3. 3) (K24) CKP SIGNAL CIRCUIT Measure the voltage on the (K24) CKP Signal circuit in the CKP Sensor harness connector. NOTE: The sensor voltage should be approximately 5.0 volts (plus or minus .1 volt) with the connector disconnected. Does the scan tool display the voltage as described above? Yes Go to 4) . No Go to 7) .
4. 4) (K900) SENSOR GROUND CIRCUIT OPEN Turn the ignition off. Disconnect the C2 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 (K900) Sensor ground circuit from the CKP Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (K900) Sensor ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K24) CKP SIGNAL CIRCUIT SHORTED TO THE (F855) 5-VOLT SUPPLY CIRCUIT Measure the resistance between the (K24) CKP Signal circuit and the (F855) 5-volt Supply circuit in the CKP Sensor harness connector. Is the resistance below 5.0 ohms? Yes Repair the short between the (K24) CKP Signal circuit and the (F855) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) CRANKSHAFT POSITION SENSOR NOTE: Inspect the slots on the flywheel for damage. If a problem is found repair as necessary. If there are no possible causes remaining, view repair. Repair Replace the Crankshaft Position Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (K24) CKP SIGNAL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (K24) CKP Signal circuit in the CKP Sensor harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K24) CKP Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (K24) CKP SIGNAL 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 (K24) CKP Signal circuit from the CKP Sensor 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 in the (K24) CKP Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) (K24) CKP SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K24) CKP Signal circuit in the CKP Sensor harness connector. Is the resistance below 5.0 ohms? Yes Repair the short to ground in the (K24) CKP Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 13) .
10. 10) (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (F855) 5-volt Supply circuit in the CKP Sensor harness connector. Is there any voltage present? Yes Repair the short to voltage in the (F855) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 11) .
11. 11) (F855) 5-VOLT SUPPLY 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 (F855) 5-volt Supply circuit from the CKP Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 12) . No Repair the open in the (F855) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
12. 12) (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (F855) 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) 5-volt Supply circuit. 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) .
14. 14) ERRATIC CKP SENSOR SIGNAL Turn the ignition off. With a lab scope probe and the Miller special tool #6801, backprobe the (K24) CKP Signal circuit in the CKP harness connector. 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. Ignition on, engine not running. Wiggle the related wire harness and lightly tap on the Crank Position Sensor. Observe the lab scope screen. Look for any pulses generated by the CKP Sensor. Allow the engine to idle. Observe the lab scope screen. Did the CKP Sensor generate any erratic pulses? Yes Inspect the related wire harness and replace the Crankshaft Position Sensor if no wiring problems were found. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 15) .
15. 15) ERRATIC CMP SIGNAL Turn the ignition off. With a lab scope probe and the Miller special tool #6801, backprobe the (K44) CMP Signal circuit in the CMP harness connector. 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. Ignition on, engine not running. Wiggle the related wire harness and lightly tap on the Cam Position Sensor. Observe the lab scope screen. Look for any pulses generated by the CMP Sensor. Allow the engine to idle. Observe the lab scope screen. Did the CMP Sensor generate any pulses? Yes Inspect the related wire harness and replace the Camshaft Position Sensor if no wiring problems were found. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Test complete, the conditions that set this DTC are not present at this time.

1. When Monitored: While cranking the engine and with the engine running.

1. Set Condition: When the CKP Sensor failure counter reaches 20. 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: During engine cranking and with the engine running. Battery voltage greater than 10 volts.

1. Set Condition: At least 5 seconds or 2.5 engine revolutions have elapsed with crankshaft position sensor signals present but no camshaft position sensor signal. 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 256

Scheme 257

Scheme 258

Scheme 259

Scheme 260

Scheme 261

Scheme 262

Scheme 263

1. 1) ACTIVE DTC Crank the engine. Ignition on, engine not running. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 2) . No Go to 14) .
2. 2) (F856) 5-VOLT SUPPLY CIRCUIT Turn the ignition off. Disconnect the CMP Sensor harness connector. Ignition on, engine not running. Measure the voltage on the (F856) 5-volt Supply circuit in the CMP Sensor harness connector. Is the voltage between 4.5 and 5.2 volts? Yes Go to 3) . No Go to 10) .
3. 3) (K44) CMP SIGNAL CIRCUIT Measure the voltage on the (K44) CMP Signal circuit in the CMP Sensor harness connector. Is the voltage between 4.5 and 5.0 volts? Yes Go to 4) . No Go to 7) .
4. 4) (K900) SENSOR GROUND CIRCUIT OPEN Turn the ignition off. Disconnect the C2 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 (K900) Sensor ground circuit from the CMP Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the (K900) Sensor ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (K44) CMP SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT Measure the resistance between the (K44) CMP Signal circuit and the (F856) 5-volt Supply circuit in the CMP Sensor harness connector. Is the resistance below 5.0 ohms? Yes Repair the short between the (K44) CMP Signal circuit and the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) CAMSHAFT POSITION SENSOR NOTE: Inspect the Camshaft sprocket for damage per the Service Information. If a problem is found repair as necessary. If there are no possible causes remaining, view repair. Repair Replace the Camshaft Position Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (K44) CMP SIGNAL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C2 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (K44) CMP Signal circuit in the CMP Sensor harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K44) CMP Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (K44) CMP SIGNAL 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 (K44) CMP Signal circuit from the CMP Sensor 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 in the (K44) CMP Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) (K44) CMP SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (K44) CMP Signal circuit in the CMP Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K44) CMP Signal circuit Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 10) .
10. 10) (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C1 PCM harness connector. Ignition on, engine not running. Measure the voltage on the (F856) 5-volt Supply circuit in the CMP Sensor harness connector. Is there any voltage present? Yes Repair the short to voltage in the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 11) .
11. 11) (F856) 5-VOLT SUPPLY 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 (F856) 5-volt Supply circuit between the CMP Sensor harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 12) . No Repair the open in the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
12. 12) (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (F856) 5-volt Supply circuit in the CMP Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (F856) 5-volt Supply circuit. 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) .
14. 14) ERRATIC CMP SIGNAL With a lab scope probe and the Miller special tool #6801, back probe the (K44) CMP Signal circuit in the CMP harness connector. 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. Ignition on, engine not running. Wiggle the related wire harness and lightly tap the Camshaft Position Sensor. Observe the lab scope screen. Allow the engine to idle. Observe the lab scope screen. Did the CMP Sensor generate any erratic pulses? Yes Replace the Camshaft Position Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 15) .
15. 15) ERRATIC CKP SIGNAL Turn the ignition off. With a lab scope probe and the Miller special tool #6801, backprobe the (K24) CKP Signal circuit in the CKP harness connector. 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. Ignition on, engine not running. Wiggle the related wire harness and lightly tap on the Crankshaft Position Sensor. Observe the lab scope screen. Allow the engine to idle. Observe the lab scope screen. Did the CKP Sensor generate any erratic pulses? Yes Replace the Crankshaft Position Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Test complete, the conditions that set this DTC are not present at this time

1. When Monitored: While cranking the engine and engine running.

1. Set Condition: When the failure counter reaches 20. 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: Engine running for greater than two minutes with the Engine Coolant Temp greater than 70° C (158° F). EGR active. Less than 8500 feet. Ambient temperature greater than -6° C (20° F).

1. Set Condition: The PCM closes the EGR valve while monitoring the O2 Sensor signal. Once a closed EGR fueling sample has been established the PCM then ramps in EGR and additional fueling while monitoring the O2 sensor signal in the open state. A fueling sample is again established. The PCM then compares the different O2 Sensor signal readings (fueling samples). If a larger than expected variation is detected, a soft failure is recorded. Three soft failures set a one trip failure. After two failed trips, a DTC is set and the MIL is illuminated.

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

Scheme 264

Scheme 265

Scheme 266

1. 1) ACTIVE DTC NOTE: Diagnose and repair any EGR circuit DTCs before continuing with this procedure. Turn the ignition on. With the scan tool, select View DTCs. Copy DTC and Freeze Frame information. 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. NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set. With a scan tool, select View DTCs. 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) ROUGH IDLE OR STALLING AT IDLE Turn the ignition off. Turn all accessories off. Start the engine. 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. Does the engine run rough or stall at idle? Yes Go to 3) . No Go to 5) .
3. 3) EGR VALVE ASSEMBLY CONTROL CIRCUIT Turn the ignition off. Disconnect the EGR Valve Assembly harness connector. Start the engine. 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. Does the engine continue to run rough or stall with the EGR Valve Assembly connector disconnected? Yes Go to 8) . No Go to 4) .
4. 4) (K35) EGR SOLENOID CONTROL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C2 PCM harness connector. Disconnect the EGR Solenoid harness connector. Ignition on, engine not running. Measure the voltage on the (K35) EGR Solenoid Control circuit in the EGR Solenoid connector. Is there any voltage present? Yes Repair the short to voltage in the (K35) EGR Solenoid Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
5. 5) EGR SYSTEM TEST Turn all accessories off. 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. With the scan tool, perform the EGR System Test. Select OPEN to open the EGR valve. Did the engine run rough or stall when the valve was opened during the system test? Yes Go to 8) . No Go to 6) .
6. 6) (Z42) EGR SOLENOID GROUND CIRCUIT OPEN Turn the ignition off. Using a 12-volt test light connected to battery voltage, probe the (Z42) EGR Solenoid ground circuit in the EGR Solenoid harness connector. Does the 12-volt test light illuminate brightly? Yes Go to 7) . No Repair the open in the (Z42) EGR Solenoid ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (K35) EGR CONTROL CIRCUIT HIGH RESISTANCE Turn the ignition off. Connect the EGR Valve Assembly 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 along with the #8815-1 to perform the diagnosis. Using a voltmeter, perform a voltage drop test by backprobing the (K35) EGR Control circuit at the EGR Valve Assembly harness connector and probing the appropriate terminal of the special tool #8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter. 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. With the scan tool, perform the EGR System Test. Select OPEN to open the EGR valve. Monitor the circuit voltage on the voltmeter. Is the voltage below 0.5 volts when the valve was opened during the system test? Yes Go to 8) . No Repair the (K35) EGR Control circuit for excessive resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) EGR VALVE ASSEMBLY WARNING: The normal operating temperature of the EGR system is very high. Never work around or attempt to service any part of the EGR system until it has cooled. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Valve Assembly 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 EGR Solenoid and the Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Inspect the EGR Valve Assembly for the following: - Proper mounting, leaking gasket(s) - Damaged, leaking, or obstructed EGR tube(s) - Carbon build up on or near the EGR pintle or within passages. Were any problem found? Yes Repair or replace the EGR system components as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace the EGR Valve Assembly. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid Assembly 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 Solenoid and the 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: Engine running. Battery voltage greater than 10 volts.

1. Set Condition: The EGR solenoid control circuit is not in the expected state when requested to operate by the PCM. One Trip Fault.

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

Scheme 267

1. 1) DTC IS ACTIVE Turn the ignition on. With the scan tool, Clear DTCs in the Powertrain Control Module (PCM). With the scan tool, actuate the EGR Valve Solenoid Duty Cycle to 79.9%. 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) (K35) EGR CONTROL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the EGR Valve Assembly connector. Disconnect the C2 PCM harness connector. Turn the ignition on. Measure the voltage of the (K35) EGR Control circuit in the EGR Valve Assembly harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K35) EGR Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K35) EGR CONTROL CIRCUIT SHORTED TO GROUND Turn the ignition off. Measure the resistance between ground and the (K35) EGR Control circuit in the EGR Valve Assembly harness connector. Is the resistance above 100 ohms? Yes Go to 4) . No Repair the short to ground in the (K35) EGR Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (K35) EGR CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 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 (K35) EGR Control circuit between the EGR Valve Assembly harness connector and the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the excessive resistance in the (K35) EGR Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (Z42) GROUND CIRCUIT OPEN OR HIGH RESISTANCE Using a 12 volt test light connected to 12 volts, check the (Z42) Ground circuit in the EGR Valve Assembly harness connector. NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery. Is the test light illuminated and bright? Yes Go to 6) . No Repair the excessive resistance in the (Z42) Ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) EGR VALVE ASSEMBLY Connect the C2 PCM harness connector. Turn the ignition on. With the scan tool, actuate the EGR Valve Solenoid Duty Cycle. Select the Duty Cycle reading of 79.9% Using a 12 volt test light connected to ground, check the (K35) EGR Control circuit in the EGR Valve Assembly harness connector. NOTE: If the DTC is active, the actuation test may not be allowed by the PCM. If may be necessary to clear the DTCs before starting the actuation. NOTE: The voltage supplied to the solenoid circuit during the actuation may be less than battery voltage. The test light should be illuminated, but may not be as bright as a direct connection to the battery. 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 accordingly during the actuation? Yes Verify that there is good pin to terminal contact in the Solenoid and the Powertrain Control Module connectors. Replace the EGR Valve Assembly in accordance with the Service Information if no problems were found with the connectors. 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 EGR Solenoid Assembly 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 Solenoid and the Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: Engine running.

1. Set Condition: The EGR flow or valve movement is not what is expected. A rationality error has been detected fro the EGR Close Position Performance. Two trip fault.

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

Scheme 268

Scheme 269

Scheme 270

1. 1) ACTIVE DTC NOTE: Diagnose and repair any EGR signal circuit high or low DTCs before continuing with this procedure. Turn the ignition on. With the scan tool, select View DTCs. Record DTC and Freeze Frame information. 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. WARNING: The normal operating temperature of the EGR system is very high. Never work around or attempt to service any part of the EGR system until it has cooled. NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set. With a scan tool, select View DTCs. 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) (F856) 5 VOLT SUPPLY CIRCUIT HIGH RESISTANCE 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 along with the #8815-1 to perform the diagnosis. Using a voltmeter, perform a voltage drop test by backprobing the (F856) 5 Volt Supply circuit at the EGR Valve Assembly harness connector and probing the appropriate terminal of the special tool #8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter. 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. Is the voltage below 0.5 volts? Yes Go to 3) . No Repair the (F856) 5 Volt Supply circuit for high resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) (K34) EGR SIGNAL CIRCUIT HIGH RESISTANCE 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 along with the #8815-1 to perform the diagnosis. Using a voltmeter, perform a voltage drop test by backprobing the (K34) EGR Signal circuit at the EGR Valve Assembly harness connector and probing the appropriate terminal of the special tool #8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter. 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. Is the voltage below 0.5 volts? Yes Go to 4) . No Repair the (K34) EGR Signal circuit for high resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (K900) SENSOR GROUND CIRCUIT HIGH RESISTANCE 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 along with the #8815-1 to perform the diagnosis. Using a voltmeter, perform a voltage drop test by backprobing the (K900) Sensor Ground circuit at the EGR Valve Assembly harness connector and probing the appropriate terminal of the special tool #8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter. 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. Is the voltage below 0.5 volts? Yes Go to 5) . No Repair the (K900) Sensor Ground circuit for high resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (Z42) GROUND CIRCUIT OPEN OR HIGH RESISTANCE Turn the ignition off. Disconnect the EGR Valve Assembly harness connector. Using a 12 volt test light connected to the 12 volts, check the (Z42) Ground circuit in the EGR Valve Assembly harness connector. NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery. Is the test light illuminated and bright? Yes Go to 6) . No Repair the (Z42) Ground circuit for an open circuit of high resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) (K35) EGR CONTROL CIRCUIT HIGH RESISTANCE Turn the ignition off. Connect the EGR Valve Assembly 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 along with the #8815-1 to perform the diagnosis. Using a voltmeter, perform a voltage drop test by backprobing the (K35) EGR Control circuit at the EGR Valve Assembly harness connector and probing the appropriate terminal of the special tool #8815. Make sure the voltmeter leads are connected so that positive polarity is displayed on the voltmeter. 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. With the scan tool, perform the EGR System Test. Select OPEN to open the EGR valve. Monitor the circuit voltage on the voltmeter. Is the voltage below 0.5 volts when the valve was opened during the system test? Yes Go to 7) . No Repair the (K35) EGR Control circuit for excessive resistance. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) EGR VALVE ASSEMBLY Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Valve Assembly and the Powertrain Control Module (PCM). Look for any chafed, pierced, pinched, or partially broken wires. Verify that there is good pin to terminal contact in the Solenoid and the Powertrain Control Module connectors. Look for broken, bent, pushed out or corroded terminals. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair or replace the EGR system components as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace the EGR Valve Assembly. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: With the ignition on. Battery voltage above 10.0 volts.

1. Set Condition: EGR Position Sensor Signal is less than the minimum acceptable value. One trip Fault.

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

Scheme 271

Scheme 272

Scheme 273

Scheme 274

1. 1) ACTIVE DTC Start the engine and allow it to reach normal 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. NOTE: Diagnose and repair any system voltage or sensor supply voltage DTCs before continuing with this test. 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) (F856) 5-VOLT SUPPLY CIRCUIT Turn the ignition off. Disconnect the EGR Solenoid harness connector. Ignition on, engine not running. Measure the voltage of the (F856) 5-volt Supply circuit in the EGR Solenoid harness connector. Is the voltage between 4.5 to 5.2 volts? Yes Go to 3) . No Go to 7) .
3. 3) (K34) EGR POSITION SENSOR SIGNAL CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C2 PCM harness connector. Measure the resistance between ground and the (K34) EGR Position Sensor Signal circuit in the EGR Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground circuit in the (K34) EGR Position Sensor Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (K34) EGR SENSOR SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT Measure the resistance between the (K34) EGR Position Sensor Signal circuit and (K900) Sensor ground circuit in the EGR Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short between the (K900) Sensor ground and the (K34) EGR Position Sensor Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) EXCESSIVE RESISTANCE IN THE (K34) EGR SIGNAL CIRCUIT 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 (K34) EGR Signal circuit between the Exhaust Gas Recirculation Valve harness connector and the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 6) . No Repair the excessive resistance in the (K34) EGR Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) EXHAUST GAS RECIRCULATION VALVE Turn the ignition off. Connect the C2 PCM harness connector. Turn the ignition on. With the scan tool, read the Exhaust Gas Recirculation Valve signal voltage. NOTE: The sensor voltage should be approximately 5.0 volts (plus or minus .1 volt) with the connector disconnected. Does the scan tool display the voltage as described above? Yes Verify that there is good pin to terminal contact in the Solenoid and the Powertrain Control Module connectors. Replace the EGR Valve Assembly in accordance with the Service Information if no problems were found with the connectors. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
7. 7) (F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C1 PCM harness connector. Measure the resistance between ground and the (F856) 5-volt Supply circuit in the EGR Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (F856) 5-VOLT SUPPLY 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 (F856) 5-volt Supply circuit from the EGR Solenoid 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 in the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid Assembly 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 Solenoid and the 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: With the ignition on. Battery voltage greater than 10 volts.

1. Set Condition: EGR position sensor signal is greater than 4.5 volts. One trip Fault.

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

Scheme 275

Scheme 276

Scheme 277

1. 1) ACTIVE DTC Turn the ignition on. With the scan tool, select View DTCs. Record DTC and Freeze Frame information. Start the engine and allow it to reach normal 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. WARNING: The normal operating temperature of the EGR system is very high. Never work around or attempt to service any part of the EGR system until it has cooled. NOTE: Attempt to operate the vehicle under conditions similar to which the DTC was set. NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions 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) (K34) EGR POSITION SENSOR SIGNAL CIRCUIT SHORTED TO THE (F856) 5-VOLT SUPPLY CIRCUIT Turn the ignition off. Disconnect the EGR Solenoid harness connector. Disconnect the C1 and C2 PCM harness connectors. Measure the resistance between the (K34) EGR Position Sensor Signal circuit and the (F856) 5-volt Supply circuit in the EGR Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short between the (K34) EGR Position Sensor Signal circuit and the (F856) 5-volt Supply circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K34) EGR POSITION SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE Ignition on, engine not running. Measure the voltage on the (K34) EGR Sensor Signal circuit in the EGR Solenoid harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K34) EGR Position Sensor Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) EGR SOLENOID ASSEMBLY Turn the ignition off. Connect the PCM harness connectors. Ignition on, engine not running. With the scan tool, monitor the EGR Position Sensor voltage. Connect a jumper wire between the (K34) EGR Position Sensor Signal circuit and the (K900) Sensor ground circuit. NOTE: The sensor voltage should be approximately 0.0 volts (plus or minus .1 volt) with the jumper wire in place. Does the scan tool display the voltage as described above? Yes Verify that there is good pin to terminal contact in the EGR Solenoid and the Powertrain Control Module connectors. Replace the EGR Valve Assembly in accordance with the Service Information if no problems were found with the connectors. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) . NOTE: Remove the jumper wire before continuing.
5. 5) (K34) EGR POSITION SENSOR SIGNAL CIRCUIT OPEN Turn the ignition off. Disconnect the C2 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 (K34) EGR Position Sensor Signal circuit from the EGR Solenoid harness connector 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 (K34) EGR Position Sensor Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) (K900) SENSOR GROUND CIRCUIT OPEN Measure the resistance of the (K900) Sensor ground circuit from the EGR Solenoid harness connector to the appropriate terminal of special tool #8815. Is the resistance below 30 ohms? Yes Go to 7) . No Repair the open in the (K900) Sensor ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the EGR Solenoid Assembly 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 Solenoid and the 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 278

1. When Monitored: The monitor will run at between 1400 and 2300 RPM. It also runs between 40 and 70 kPa.

1. Set Condition: If the final State of Change index is within the calibrated fail threshold. Two 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 279

Scheme 280

Scheme 281

1. 1) ACTIVE DTC NOTE: A new rear O2 Sensor along with an aging front O2 Sensor may cause the DTC to set. Review the repair history of the vehicle before continuing. NOTE: If an O2 Sensor DTC set along with the Catalytic Converter Efficiency DTC diagnose the O2 Sensor DTC(s) before continuing. NOTE: Check for contaminants that may have damaged the O2 Sensor and Catalytic Converter: contaminated fuel, unapproved silicone, oil and coolant, repair 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) VISUALLY INSPECT CATALYTIC CONVERTER Inspect the Catalytic Converter for the following damage. Damage Catalytic Converter, dents or holes. Severe discoloration caused by overheating the Catalytic Converter. Catalytic Converter broke internally. Inspect both ends of the converter, inlet and outlet. Leaking Catalytic Converter. Were any problems found? Yes Replace the Catalytic Converter. Repair the condition that may have caused the failure. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (K902) O2 RETURN UPSTREAM CIRCUIT VOLTAGE CHECK Turn the ignition off. Disconnect the 1/1 O2 Sensor harness connector. Turn the ignition on. Measure the voltage on the (K902) O2 Return Upstream circuit in the O2 Sensor harness connector. Is the voltage at 2.5 volts? Yes Go to 4) . No Go to 5) .
4. 4) (K904) O2 RETURN DOWNSTREAM CIRCUIT VOLTAGE CHECK Turn the ignition off. Disconnect the 1/2 O2 Sensor harness connector. Turn the ignition on. Measure the voltage on the (K904) O2 Return Downstream circuit in the O2 Sensor harness connector. Is the voltage at 2.5 volts? Yes Go to 10) . No Go to 7) .
5. 5) (K902) O2 RETURN UPSTREAM CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C1 and C2 PCM harness connectors. Measure the resistance between ground and the (K902) O2 Return Upstream circuit in the 1/1 O2 Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K902) O2 Return Upstream circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (K902) O2 RETURN UPSTREAM CIRCUIT OPEN Measure the resistance of the (K902) O2 Return Upstream circuit from the 1/1 O2 Sensor 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 in the (K902) O2 Return Upstream circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (K904) O2 RETURN DOWNSTREAM CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the 1/2 O2 harness connector. Measure the resistance between ground and the (K904) O2 Return Downstream circuit in the 1/2 O2 Sensor harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K904) O2 Return Downstream circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (K904) O2 RETURN DOWNSTREAM CIRCUIT OPEN Measure the resistance of the (K904) O2 Return Downstream circuit from the 1/2 O2 Sensor 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 in the (K904) O2 Return Downstream circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Sensor 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 Sensor and the 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) .
10. 10) CHECKING THE EXHAUST SYSTEM FOR LEAKS Turn the ignition off. Raise the vehicle in accordance with the Service Information. WARNING: The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operating time. Connect Exhaust Cone #8404-EC or #8404-EC to Air Pressure Regulator (with hose) #W-18-MIL-1146AS. CAUTION: The air pressure must not exceed 27.6 kPa (4 psi), otherwise engine damage can occur. Attach shop air to the air pressure regulator. Adjust the Air Pressure Regulator to 27.6 kPa (4 psi) Insert the exhaust cone into the vehicle tail pipe. If the vehicle is equipped with dual exhaust. Use the #8404-ECT with equipped attached plug, plug one side of the dual exhaust pipe. Pressurize the other as described above. Apply SNOOP leak finder liquid or a mixture of liquid dish soap and water to the following areas: - All welded joints from the exhaust manifold to 152.4 mm (6 inches) behind the downstream O2 sensor - O2 sensor seal points - O2 sensor boss welds - Flange/joint connection(s) - Exhaust manifold to cylinder head connection(s) - EGR solenoid gasket base and tube seal points (if equipped) Watch for the liquid/soapy water to bubble. Use the following definitions to help determine if system or component repair/replacement is necessary: Type 1 Leak is defined as a leak where very small foam like bubbles 1 mm (0.04 of an inch) or less appear. Any Type 1 or greater leaks found in welded joints, O2 sensor seal points or O2 sensor boss welds must be repaired or the component must be replaced. Type 2 Leak is defined as a leak where larger bubbles pea size, 8 mm (0.3 of an inch) or greater appear. Any Type 2 or greater leaks found in flange or joint connections, exhaust manifold to cylinder head connections, or EGR gasket and tube seal points must be repaired or the components must be replaced Leak Location Repair required if results at 4 psi reveal bubble size: Welded joints Type 1, 1 mm (0.04 of an inch) or greater O2 Sensor seal points Type 1, 1 mm (0.04 of an inch) or greater O2 Sensor boss welds Type 1, 1 mm (0.04 of an inch) or greater Flange / joint connections Type 2, 8 mm (0.3 of an inch) or greater Exhaust Manifold to cylinder head connections Type 2, 8 mm (0.3 of an inch) or greater EGR gasket and tube seal points Type 2, 8 mm (0.3 of an inch) or greater If a leak is found that matches the above definition, repair or replace the component as necessary. Once the repair is complete, repeat the procedure to verify that all leaks have been repaired. Were any exhaust leaks found? Yes Repair or replace the leaking exhaust parts as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 11) .
11. 11) ENGINE MECHANICAL CONDITION Check the exhaust for excessive smoke caused by an internal problem in the engine. Is an engine mechanical condition present? Yes Repair the engine mechanical condition as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 12) .
12. 12) AGING O2 SENSOR A new rear O2 Sensor along with an aging front O2 Sensor may cause the DTC to set. Review the vehicles repair history. Has the rear O2 Sensor been replaced without replacing the front O2 Sensor? Yes Replace the Front O2 Sensor as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 13) .
13. 13) CATALYTIC CONVERTER If there are no possible cause remaining, view repair. Repair Replace the Catalytic Converter. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

Scheme 282

1. When Monitored: The monitor will run at between 1400 and 2300 RPM. It also runs between 40 and 70 kPa.

1. Set Condition: If the final State of Change index is within the calibrated fail threshold. Two 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: Engine running after a cold start with the difference between ECT and AAT is less than 10° C (19° F). Fuel Level between 12% and 88% full. Manifold vacuum greater than a calculated minimum value. Ambient Temperature between 4° C and 32° C (39° F and 89° F).

1. Set Condition: When the monitor conditions are met, the PCM will ramp in purge flow. If the PCM does not sense an ESM switch closure after a calculated amount of purge flow accumulation, an error is detected. Two 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 283

Scheme 284

Scheme 285

Scheme 286

Scheme 287

Scheme 288

1. 1) VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION Ignition on, engine not running. With a scan tool, select View DTCs. Record the related Freeze Frame data if any DTC(s) are present. Whether or not any DTC(s) are active you will want to check the following items which may assist in repairing the customer's complaint successfully. Check the vehicles repair history. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly. Check for any service bulletin(s) related to the customer's complaint or DTCs. If a service bulletin applies, follow the instructions per the service bulletin. Choose the following scenario that best applies. The service bulletin repaired the customer's complaint. Testing complete. A DTC is present, no service bulletins apply, or the service bulletin didn't repair the customer's complaint. Go to 2) .
2. 2) ACTIVE DTC NOTE: Allow the vehicle to reach ambient temperature before continuing with this procedure. NOTE: A loose gas cap could have caused this DTC to set. Make sure the gas cap is tight and in good condition. NOTE: If the customer is experiencing an early fuel shut off during the fuel filling process along with P0440, P0441, and P0452 setting, you need to check for restrictions in the Evap Purge tubes/hoses as well as the Fresh Air Filter before continuing. 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 3) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
3. 3) VISUAL AND PHYSICAL INSPECTION Turn the ignition off. Perform a visual and physical inspection of the entire Evaporative Emission system. Check for the following conditions: - Hoses disconnected or left off - Holes or cracks - Loose seal points - Evidence of damaged components - Incorrect routing of hoses and tubes - Fuel Cap left off or bad gasket seal Were any of the above conditions found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) EVAP VACUUM SUPPLY HOSE INSPECTION Carefully inspect the Evap Purge Solenoid vacuum supply hose for proper routing. Check for a pinched or plugged hose from the throttle body or intake manifold to the Purge Solenoid. Make sure the vacuum port at the throttle body or intake manifold is free from any blockage. Were any problems found? Yes Repair the vacuum supply, hose/tube as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) EVAP PURGE SOLENOID NOTE: To continue testing you will need Miller Tool #8404 Evaporative Emission Leak Detector (EELD). WARNING: Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases, Keep the test area well ventilated. Connect the red power lead of the EELD to the battery positive terminal and the black ground lead to battery negative terminal. Disconnect the vacuum hoses at the Evap Purge Solenoid. Connect the SMOKE supply tip (black hose) to the "CAN" port on the Evap Purge Solenoid. Set the smoke/air control switch to SMOKE. While still holding the remote smoke/air start button, check to see if smoke is exiting the purge valve. This indicates that there is a leak internal to the purge valve. NOTE: This is an optional method of checking the purge valve for leaks if the EELD is unavailable. Disconnect the Smoke supply tip from the vacuum supply hoses at the Evap Purge Solenoid. Using a hand vacuum pump, apply 10 inches of Hg to the "CAN" side of the Evap Purge Solenoid. Observe the vacuum gauge for at least 15 seconds. Is smoke visible from the Evap Purge Solenoid or NOT hold a vacuum? Yes Replace the Evap Purge Solenoid. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) ESIM SWITCH STATE Turn the ignition off. Connect the previously disconnected vacuum hose. Disconnect the Evap System Monitor Switch harness connector. Ignition on, engine not running. Monitor the ESIM Switch state on the scan tool. Carefully connect a jumper wire between the (K107) ESM Signal circuit and the (Z910) Ground circuit in the Evap System Monitor Switch harness connector. Monitor the ESIM Switch state on the scan tool. Did the Switch change from OPEN to CLOSED when the jumper wire was installed? Yes Go to 9) . No Go to 7) .
7. 7) EXCESSIVE RESISTANCE IN THE (K107) ESM SIGNAL CIRCUIT 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 (K107) ESM Signal circuit from the ESM harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 8) . No Repair the excessive resistance in the (K107) ESM Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) EXCESSIVE RESISTANCE IN THE (Z910) GROUND CIRCUIT Using a 12-volt test light connected to B+, probe the (Z910) Ground circuit in the ESM harness connector. NOTE: The test light should illuminate brightly. Compare the brightness to that of a direct connection to B- (ground). Does the test light illuminate brightly? Yes Go to 14) . No Repair the excessive resistance in the (Z910) Ground circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
9. 9) VERIFY EVAPORATIVE EMISSION LEAK WARNING: Keep lit cigarettes, sparks, flames, and other ignition sources away from the test area to prevent the ignition of explosive gases. Keep the test area well ventilated. Turn the ignition off. To continue testing you will need Miller Tool #8404 Evaporative Emission Leak Detector (EELD). NOTE: The fuel tank should have between 20% and 80% of fuel tank capacity to properly test the Evap system. Connect the red power lead of EELD to the battery positive terminal and the black ground lead to battery negative terminal. Block the vent hose of the Evap Canister. Connect shop air to the EELD. Set the smoke/air control switch to AIR. Insert the tester's AIR supply tip (clear hose) into the .040 orifice on the tester's control panel. Press the remote smoke/air start button. Position the red flag on the air flow meter so it is aligned with the indicator ball. When the calibration is complete, release the remote button. The EELD flow meter is now calibrated in liters per minute. Install the service port adapter #8404-14 on the vehicle's service port (if equipped) or install the #8404-ADP into the filter line. Connect the Air supply hose from the EELD to the service port (if equipped) or to the #8404-ADP adapter. Press the remote button to activate AIR flow. Compare the flow meter indicator ball reading to the red flag. ABOVE the red flag indicates a leak present. BELOW the red flag indicates a sealed system. Is the indicator ball above the red flag? Yes Go to 10) . No Go to 12) .
10. 10) EVAPORATIVE EMISSION LEAK DETECTION NOTE: A thorough visual inspection of the Evap system hoses, tubes, and connections may save time in your diagnosis. Look for any physical damage or signs of wetness at connections. The strong smell of fuel vapors may aid diagnosis also. Remove the Air supply hose from the service port or the #8404-ADP adapter. Connect the SMOKE supply tip (black hose) to the service port (if equipped) or to the #8404-ADP adapter. Set the smoke/air control switch to SMOKE. NOTE: The flow meter indicator ball will not move at this point. Press the remote smoke/air start button. NOTE: Make sure that smoke has filled the Evap system by continuing to press the remote smoke/air start button, remove the vehicle fuel cap, and wait for the smoke to exit. Once smoke is indicated reinstall the fuel cap. NOTE: For optimal performance, introduce smoke into the system for an additional 60 seconds; continue introducing smoke at 15 second intervals, as necessary. While still holding the remote smoke/air start button, use the white light (#8404-CLL) to follow the Evap system path, and look for the source of the leak indicated by exiting smoke. If a leak is concealed from view (i.e, top of fuel tank), release the remote smoke/air start button, and use the ultraviolet (UV) black light #8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that are left behind by the smoke. The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a UV light. NOTE: The Evap System is divided into three zones. A leak from any of these zones can cause this DTC to set. The lists below specify the possible leak points in that specific zone. For further assistance see the Zone Identification Charts shown in the illustrations below. ZONE 1 1 Fuel Cap 2 Recirculation Check Valve. 3 Vapor Recirculation Line. 4 Signal Vapor Line for FVM. 5 Flow Management Valve. 6 Fuel Tank to Canister Vapor Line connection. 7 Fuel Tank Vent (Check Valve). 8 Vapor Line to Canister. 9 Flow Control Orifice. 10 Control Valve. 11 Liquid Trap. 12 Fuel Tank. 13 Check valve. 14 Fuel Fill Tube to Tank connector. 15 Fuel Fill Tube Damaged or disconnected Evap System components. ZONE 2 1 Filter. 2 ESIM. 3 Canister Vent Line. 4 Evap Canister. 5 Chassis Purge Valve. 6 Fuel Tank to Canister Vapor Line connection. 7 Evap Purge connection. ZONE 3 1 Evap Purge Vacuum Line. 2 Connection to Chassis Line. 3 Connection to Canister. 4 Chassis Purge Line. 5 Evap Purge Vacuum Line. 6 Connection to Evap Purge Harness. 7 Chassis Evap Purge Line connection to Engine Vacuum. 8 Evap Purge Valve. 9 Service Port. NOTE: Carefully inspect the vent side of the Evap Canister. Due to the filtering system in the canister the smoke or dye may or may not be visible. Introducing smoke into the filtered side of the canister may assist in locating the leak. Select the appropriate response from the list below: A leak was found at the gas cap or fuel filler tube. Go to 11) . A leak was found in one or more of the Evap System zones. If the leak is at a hose connection, remove the hose then reconnect the hose and check for a leak again. All other leaks repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No leaks were detected. Go to 12) .
11. 11) LEAK AT GAS CAP Remove the SMOKE supply tip (black hose) from the service port (if equipped) or to the #8404-ADP adapter. Install gas cap adapter, Miller Tool #8382 (1/4 turn cap) or #6922 (screw cap) and #8399* (secondary seal depressor) and repeat test 5. NOTE: The gas cap adapter is being used as a known good cap. Was a leak found at the gas cap adapter? Yes Replace the Fuel Filler tube assembly. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace the gas cap. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
12. 12) EVAP PURGE HOSE/TUBE AND FRESH AIR FILTER OBSTRUCTION Inspect the Evap Purge hose/tube for proper routing and installation between the Evap Purge Solenoid and the Fuel Tank between the Fuel Tank and the Evap Purge Canister Make sure the hose/tube and fresh air filter are not damaged, kinked, and free from any obstructions. Were any problems found? Yes Repair or replace as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 13) .
13. 13) EVAP SYSTEM MONITOR SWITCH Use the wiring diagram/schematic as a guide, inspect the wiring and connections between the Evap System Monitor Switch and the 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 ESIM Switch and the Powertrain Control Module connectors. Look for any broken, bent, pushed out, or corroded terminals. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair and Replace as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace the Evap System Monitor Switch per Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
14. 14) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid Assembly, ESIM Switch 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 Switch, Solenoid, and the 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: After the Evap System small leak test has passed, with the engine running, ambient temperature between 4° C (39° F) and 35° (95° F), with the engine at idle after a calibrated amount of drive time has accumulated.

1. Set Condition: If the PCM detects that the purge vapor ratio and the ESM switch closed ratio are below a calculated value, the PCM commands the purge solenoid to flow at a specified rate to update the purge vapor ratio. If the ratio remains below a specified value, a one trip failure is recorded. Two 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 ignition on or engine running. Battery voltage greater than 10 volts.

1. Set Condition: The PCM will set a trouble code if the actual state of the solenoid does not match the intended 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 289

Scheme 290

Scheme 291

Scheme 292

Scheme 293

Scheme 294

1. 1) VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION Ignition on, engine not running. With a scan tool, select View DTCs and record the related Freeze Frame data if any DTC(s) are present. Whether or not any DTC(s) are Active you will want to check the following items which may assist in repairing the customer's complaint successfully. Check the vehicles repair history. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly. Check for any service bulletin(s) related to the customer's complaint or DTC(s). If a service bulletin applies, follow the instructions per the service bulletin. Choose the following scenario that best applies. The service bulletin repaired the customer's complaint. Testing complete. A DTC is present, no service bulletins apply, or the service bulletin didn't repair the customer's complaint. Go to 2) .
2. 2) ACTIVE DTC Ignition on, engine not running. With the scan tool, Select View DTCs. Is the DTC Active at this time? Yes Go to 3) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
3. 3) (K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the Evap Purge Solenoid harness connector. Disconnect the C3 PCM harness connector. Ignition on, engine not running. Measure the voltage of the (K52) Evap Purge Control circuit in the Evap Purge Solenoid harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K52) Evap Purge Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (K70) EVAP PURGE RETURN CIRCUIT SHORTED TO VOLTAGE Measure the voltage of the (K70) Evap Purge Return circuit in the Evap Purge Solenoid harness connector. Is there any voltage present? Yes Repair the short to voltage in the (K70) Evap Purge Return circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) (K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO GROUND Turn the ignition off. Measure the resistance between ground and the (K52) Evap Purge Control circuit in the Evap Purge Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K52) Evap Purge Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) (K52) EVAP PURGE SOLENOID CONTROL 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 (K52) Evap Purge Solenoid Control circuit from the Evap Purge Solenoid 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 in the (K52) EVAP Purge Solenoid Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) (K70) EVAP PURGE SOLENOID 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 (K70) Evap Purge Solenoid Signal circuit from the Evap Purge Solenoid harness connector to the appropriate terminal of special tool #8815. Is the resistance below 5.0 ohms? Yes Go to 8) . No Repair the open in the (K70) Evap Purge Solenoid Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
8. 8) EVAP PURGE SOLENOID Connect the C3 PCM harness connector. Ignition on, engine not running. With the scan tool, actuate the Evap Purge Solenoid control to the ON (100%) position. NOTE: The DTC needs to be cleared before actuating the Purge Solenoid, if the DTC is not cleared, the Solenoid may not be allowed to actuate. Using a 12-volt test light connected to ground, check the (K52) Evap Purge Control circuit in the Evap Purge Solenoid harness connector. NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the B- (ground). 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 accordingly during the actuation? Yes Verify that there is good pin to terminal contact in the Evap Solenoid and the Powertrain Control Module connectors. Replace the Evap Purge Solenoid if no problems were found in the connectors. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
9. 9) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid Assembly, ESIM Switch 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 Switch, Solenoid, and the 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: Immediately after the ignition has been turned off.

1. Set Condition: At key off, the PCM energizes the Purge Solenoid for a calibrated amount of time (30 seconds maximum) and stores the state of the ESIM switch. The state is evaluated again at the next key on. If the PCM does not detect that the ESIM switch is open, an error is detected. Two 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 295

1. 1) VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION Ignition on, engine not running. With a scan tool, select View DTC(s) and record the related Freeze Frame data if any DTC(s) are present. Whether or not any DTC(s) are Active you will want to check the following items which may assist in repairing the customer's complaint successfully. Check the vehicles repair history. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly. Check for any service bulletin(s) related to the customer's complaint or DTC(s). If a service bulletin applies, follow the instructions per the service bulletin. Choose the following scenario that best applies. The service bulletin repaired the customer's complaint. Testing complete. A DTC is present, no service bulletins apply, or the service bulletin didn't repair the customer's complaint. Go to 2) .
2. 2) ACTIVE DTC NOTE: If the customer is experiencing an early fuel shut off during the fuel filling process along with P0440, P0441, and P0452 setting, you need to check for restrictions in the Evap Purge tubes/hoses as well as the Fresh Air Filter before continuing. Ignition on, engine not running. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go to 3) . No Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure.
3. 3) ESIM SWITCH STATE With a scan tool, select Data Display and view the ESIM Switch state. Disconnect the purge hose from the Evap canister. Is the ESIM Switch state change from 'Closed' to 'Open' when the purge hose was disconnected? Yes Go to 4) . No Go to 7) .
4. 4) EVAP PURGE HOSE/TUBE AND FRESH AIR FILTER OBSTRUCTION Turn the ignition off. Inspect the Evap Purge hose/tube for proper routing and installation between the Evap Purge Solenoid and the Fuel Tank and between the Fuel Tank and the Evap Purge Canister. Make sure the hose/tube and fresh air filter are not damaged, kinked, and free from any obstructions. Check for any kink in the purge line connecting the LPV (Linear Purge Valve) to intake manifold. Were any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) (K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO GROUND Disconnect the C3 PCM harness connector. Measure the resistance between ground and the (K52) Evap Purge Control circuit in the Evap Purge Solenoid harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K52) Evap Purge Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) EVAP PURGE SOLENOID Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid 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 Evap Solenoid and the Powertrain Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were any problems found? Yes Repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Replace the Evap Purge Solenoid in accordance with the Service Information. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
7. 7) ESIM ASSEMBLY With a scan tool, select Data Display and view the ESIM Switch state. Disconnect the Evap System Monitor Switch electrical connector. Does the ESIM Switch state change from CLOSED to OPEN when the switch is disconnected? Yes Verify that there is good pin to terminal contact in the Switch and the Powertrain Control Module connectors. Replace the ESIM Switch Assembly if no problems were found with the connectors. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) (K107) ESM SWITCH SIGNAL CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C3 PCM harness connector. Measure the resistance between ground and the (K107) ESIM Switch Signal circuit in the ESIM Assembly harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (K107) ESIM Switch Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 9) .
9. 9) POWERTRAIN CONTROL MODULE (PCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid Assembly, ESIM Switch 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 ESIM, Evap Purge Solenoid, and the 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: With the engine running, during a cold start test with the fuel level above 12%, ambient temperature between 4° C and 32° C (39° F and 89° F) and the fuel system in closed loop. The test runs when the small leak test is maturing.

1. Set Condition: The PCM activates the Evap Purge Solenoid to pull the Evap system into a vacuum to close the ESM switch. Once the ESM switch is closed, the PCM turns the Evap Purge solenoid off to seal the Evap system. If the ESM switch reopens before the calibrated amount of time, a large leak error is detected. Two 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: With the ignition off, fuel level less than 88%, ambient temperature between 4° C and 43° C (39° F and 109° F), and the fuel system in closed loop.

1. Set Condition: As temperatures change, a vacuum is created in the fuel tank and Evap System. With the Evap System sealed, the PCM monitors the ESM switch. If the ESM switch does not close within a calibrated time, an error is detected by 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. Ambient Temperature between 4° C and 32° C (39° F and 89° F) Close Loop fuel system. Test runs after the medium leak test is inconclusive and the PCM has senses a fuel increase.

1. Set Condition: If a leak greater than .090" is detected by the PCM for two consecutive cold start trips after a significant fuel level change, this DTC will set. One good trip turns off the MIL.

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

1. When Monitored: TEST No. 1: With the ignition on, the fuel level is compared to the previous key down after a 20 second delay. TEST No. 2: The PCM monitors the fuel level at ignition on.

1. Set Condition: TEST No. 1: If the PCM does not see a difference in fuel level of greater than 0.1 volt the test will fail. TEST No. 2: If the PCM does not see a change in the fuel level of .1765 over a set amount of miles the test will fail. Two 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 296

Scheme 297

Scheme 298

Scheme 299

1. 1) ACTIVE DTC NOTE: Diagnose any CAN - C or CAN - B Communication DTCs before continuing. NOTE: Diagnose P0462 or P0463 first, if set along with P0461. 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) VISUALLY INSPECT FUEL TANK Visually inspect the Fuel Tank for damage that may restrict the Fuel Sending Unit float from moving. Is the Fuel Tank OK? Yes Go to 3) . No Replace the Fuel Tank as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) (A109) FUSED B+ CIRCUIT Using a 12-volt test light connected to ground, probe the (A109) Fused B+ circuit. Does the test light illuminate brightly? Yes Go to 4) . No Repair the open or short to ground in the (A109) Fused B+ circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (Z912), (Z210) GROUND CIRCUITS Using a 12-volt test light connected to B+, probe the (Z912) and (Z210) Ground circuits. Does the test light illuminate brightly? Yes Go to 5) . No Repair the open in the (Z912) and (Z210) Ground circuits. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN Turn the ignition off. Disconnect the Fuel Pump Module harness connector. Disconnect the C1 Cluster harness connector. Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the C1 Cluster harness connector. Is the resistance below 5.0 ohms? Yes Go to 6) . No Repair the open in the (N4) Fuel Level Signal circuit. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) .
6. 6) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the (N4) Fuel Level Signal circuit in the Fuel Pump Module harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (N4) Fuel Level Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 7) .
7. 7) INTERNAL INSPECTION OF THE FUEL TANK WARNING: The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in personal injury or death. Remove the Fuel Tank per Service Information. Remove the Fuel Pump Module. Visually inspect the inside of the Fuel Tank for any obstructions or deformities. Inspect the Fuel Pump Module Float arm for damage. Were any problems found? Yes Repair or replace as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 8) .
8. 8) FUEL LEVEL SENSOR If there are no possible causes remaining, view repair. Repair Replace the Fuel Level Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .

1. When Monitored: Ignition on and battery voltage above 10.4 volts.

1. Set Condition: The fuel level sensor signal voltage goes below the minimum acceptable value. 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 300

1. 1) ACTIVE DTC NOTE: Diagnose any CAN - B or CAN -C Communication DTCs before continuing. Ignition on, engine not running. 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) FUEL LEVEL SENSOR Turn the ignition off. Disconnect the Fuel Pump Module harness connector. Ignition on, engine not running. Using a fused jumper wire, jump the (A109) Fused B+ circuit to the (N4) Fuel Level Sensor No. 1 Signal circuit in the Fuel Pump Motor harness connector. Did the Fuel gauge level change from empty to full? Yes Verify that there is good pin to terminal contact at the Fuel Pump Module, and the Powertrain Control Module connectors. Replace the Fuel Level Sensor if no problems were found at the connectors. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (A109) FUSED B+ CIRCUIT Using a 12-volt test light connected to ground, probe the (A109) Fused B+ circuit. Does the test light illuminate brightly? Yes Go to 4) . No Repair the open or short to ground in the (A109) Fused B+ circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO GROUND Turn the ignition off. Disconnect the C1 Cluster harness connector. Measure the resistance between ground and the (N4) Fuel Level Signal circuit in the Fuel Pump Module harness connector. Is the resistance below 100 ohms? Yes Repair the short to ground in the (N4) Fuel Level Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 5) .
5. 5) (N4) FUEL LEVEL SIGNAL CIRCUIT OPEN Measure the resistance of the (N4) Fuel Level Signal circuit from the Fuel Pump Module harness connector to the C1 Cluster harness connector. Is the resistance below 5.0 ohms? Yes Go to 6) . No Repair the open in the (N4) Fuel Level Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
6. 6) INSTRUMENT CLUSTER Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the Instrument Cluster. 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 the Instrument Cluster connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) . No Replace and program the Instrument Cluster per Service Information. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) .

1. When Monitored: Ignition on and battery voltage above 10.4 volts.

1. Set Condition: The fuel level sensor signal voltage at the PCM goes above the maximum acceptable value. 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 301

1. 1) ACTIVE DTC NOTE: Diagnose any CAN - B and CAN - C Communication DTCs before continuing. 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) FUEL LEVEL SENSOR Turn the ignition off. Disconnect the Fuel Pump Module electrical harness connector. Ignition on, engine not running. Did the Fuel Level gauge change from full to empty? Yes Verify that there is good pin to terminal contact in the Fuel Pump Module and the Instrument Cluster connectors. If OK, replace the Fuel Level Sensor. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 3) .
3. 3) (N4) FUEL LEVEL SIGNAL CIRCUIT SHORTED TO VOLTAGE Turn the ignition off. Disconnect the C1 Cluster harness connector. Ignition on, engine not running. Measure the voltage on the (N4) Fuel Level Signal circuit in the Fuel Pump Module harness connector. Is there any voltage present? Yes Repair the short to voltage in the (N4) Fuel Level Signal circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 4) .
4. 4) (Z910), (Z210) GROUND CIRCUIT OPEN Turn the ignition off. Using a 12-volt test light connected to B+, probe (Z910) and (Z210) Ground circuits at the Fuel Pump Module harness connector. Does the test light illuminate brightly? Yes Go to 5) . No Repair the open in the (Z910) and (Z210) Ground circuits. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) INSTRUMENT CLUSTER Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the Instrument Cluster. 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 the Instrument Cluster connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) . No Replace and program the Instrument Cluster per Service Information. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) .

Scheme 302

1. When Monitored: With the ignition on. Battery voltage greater than 10 volts.

1. Set Condition: An open or shorted circuit is detected in the radiator fan relay 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 .

Scheme 303

Scheme 304

Scheme 305

1. 1) LOW SPEED RADIATOR FAN RELAY OPERATION NOTE: If the P0480 is setting on a 5.7L engine, refer to «P1646-HYDRAULIC COOLING FAN CONTROL CIRCUIT LOW»(ref-288294-S39675052002008062000000) . Ignition on, engine not running. With a scan tool, actuate the Low Speed Radiator Fan Relay. Is the Cooling Fan Relay operating? Yes Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure. No Go to 2) .
2. 2) FUSED B+ CIRCUITS Turn the ignition off. Remove the Radiator Fan Low Relay. Using a 12-volt test light connected to ground, probe the Fused B+ circuits. Does the test light illuminate brightly? Yes Go to 3) . No Repair the open or short to ground in the Fused B+ circuits. Inspect the related fuse and repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) RADIATOR FAN LOW RELAY RESISTANCE Measure the resistance of the Radiator Fan Low Relay Coil. Is the resistance between 60 to 80 ohms? Yes Go to 4) . No Replace the Radiator Fan Low Relay. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) RADIATOR FAN LOW RELAY CONTROL CIRCUIT OPEN Disconnect the C3 FCM harness connector. Measure the resistance of the Radiator Fan Low Relay Control circuit from the Relay to the C3 FCM harness connector. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the Radiator Fan Low Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) RADIATOR FAN LOW RELAY CONTROL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the Radiator Fan Low Relay Control circuit at the Relay connection. Is the resistance below 100 ohms? Yes Repair the short to ground in the Radiator Fan Low Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) FRONT CONTROL MODULE (FCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Radiator Fan and the Front Control Module (FCM). 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 Radiator Fan High Relay and Front Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) . No Replace Front Control Module per Service Information. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) .

1. When Monitored: With the ignition on. Battery voltage greater than 10 volts.

1. Set Condition: An open or shorted circuit is detected in the radiator fan relay 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 .

Scheme 306

Scheme 307

Scheme 308

1. 1) HIGH SPEED RADIATOR FAN RELAY OPERATION Ignition on, engine not running. With a scan tool, actuate the High Speed Radiator Fan Relay. Is the Cooling Fan Relay operating? Yes Refer to «INTERMITTENT CONDITION»(ref-288287-S02739760862008062000000) Diagnostic Procedure. No Go to 2) .
2. 2) FUSED B+ CIRCUITS Turn the ignition off. Remove the Radiator Fan High Relay. Using a 12-volt test light connected to ground, probe the Fused B+ circuits in the Relay connection. Does the test light illuminate brightly? Yes Go to 3) . No Repair the open or short to ground in the Fused B+ circuits. Inspect the related fuse and repair as necessary. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
3. 3) RADIATOR FAN HIGH RELAY RESISTANCE Measure the resistance of the Radiator Fan High Relay Coil. Is the resistance between 60 to 80 ohms? Yes Go to 4) . No Replace the Relay. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
4. 4) RADIATOR FAN HIGH RELAY CONTROL CIRCUIT OPEN Disconnect the FCM 49 way harness connector. Measure the resistance of the Radiator Fan High Relay Control circuit from the Relay connection to the C3 FCM harness connector. Is the resistance below 5.0 ohms? Yes Go to 5) . No Repair the open in the Radiator Fan High Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) .
5. 5) RADIATOR FAN HIGH RELAY CONTROL CIRCUIT SHORTED TO GROUND Measure the resistance between ground and the Radiator Fan High Relay Control circuit at the Relay connection. Is the resistance below 100 ohms? Yes Repair the short to ground in the Radiator Fan High Relay Control circuit. Perform «POWERTRAIN VERIFICATION TEST»(ref-288299-S34942598282008062000000) . No Go to 6) .
6. 6) FRONT CONTROL MODULE (FCM) Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Radiator Fan and the Front Control Module (FCM). 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 Radiator Fan High Relay and Front Control Module connectors. Refer to any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) . No Replace the Front Control Module per Service Information. Perform «BODY VERIFICATION TEST»(ref-288232-S30638820392008062000000) .

Scheme 309

1. When Monitored: With the engine running, transmission not in park or neutral, brakes not applied, and engine RPM greater than 1500.

1. Set Condition: This code will set if no vehicle speed signal is received from the ABS Module up to 120 seconds for 2 consecutive trips. Two 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 .