Diagnostic Test

WARNING: This page is about a different car, the 2009 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

SELECT THE PROPER VERIFICATION TEST
Select the verification test for the repair that has been completed:

Speed Control repair
- Go to step 2
Charging System repair
- Go to step 3
No Start repair
- Go to step 4
Diesel Particulate Filter repair
- Go to step 5
Differential Pressure Sensor repair
- Go to step 6
DTC and all other repairs
- Go to step 7
SPEED CONTROL VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. With the scan tool, erase all diagnostic trouble codes (DTCs).
3. Road test the vehicle at a speed above 60 km/h (35 MPH).
4. Turn the speed control ON/OFF switch on.
5. Depress and release the SET switch. If the speed control does not engage, the repair is not complete, continue with 12.
6. Quickly depress and release the RESUME/ACCEL switch. If the vehicle speed does not increase by 3 km/h (2 MPH), the repair is not complete, continue with 12.
7. Using caution, depress and release the brake pedal. If the speed control does not disengage, the repair is not complete, continue with 12.
8. With the vehicle speed at least 60 km/h (35 MPH), depress the RESUME/ACCEL switch. If the speed control does not resume at the previously set speed, the repair is not complete, continue with 12.
9. Hold down the COAST switch. If the vehicle does not decelerate, the repair is not complete, continue with 12.
10. While still holding down the COAST switch, make sure the vehicle speed is at least 60 km/h (35 MPH) and release the COAST switch. If the vehicle does not adjust and set a new vehicle speed, the repair is not complete, continue with 12.
11. With the speed control engaged, depress the ON/OFF switch. If the speed control does not disengage, the repair is not complete, continue with 12.
12. If the vehicle did not successfully perform all of the previous steps, check for Technical Service Bulletins (TSBs) that pertain to this speed control problem and then, if necessary, return to the DTC or non DTC list if necessary.
13. If the vehicle successfully performed all of the previous steps, the speed control system is now functioning as designed. The repair is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.
CHARGING SYSTEM VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. With the scan tool, erase all diagnostic trouble codes (DTCs).
3. Start the engine.
4. Raise the engine speed to 2000 RPM for at least 30 seconds.
5. Allow the engine to idle.
6. Turn the ignition off for 20 seconds.
7. Turn the ignition on.
8. With the scan tool, read ECM DTCs.
9. If this DTC has set again, or another DTC has set, look for any Technical Service Bulletins (TSBs) that may relate to this condition. Return to the DTC or non DTC Symptom list if necessary.
10. If the charging system is functioning correctly and there are no DTCs, the repair is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.
NO START VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.

NOTE: IMPORTANT! If the Engine Control Module or Wireless Control Module (WCM) has been replaced, make sure the programming procedure for the module has been performed in accordance with the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. Inspect the engine oil for contamination. If it is contaminated, change the oil and filter.
3. With the scan tool, erase all diagnostic trouble codes (DTCs).
4. Turn the ignition off for at least 10 seconds.
5. Attempt to start the engine.
6. If the engine is unable to start, look for any Technical Service Bulletins (TSBs) that may relate to this condition. Return to the DTC or non DTC Symptom List if necessary.
7. If the engine starts and continues to run, the repair is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.
DIESEL PARTICULATE FILTER VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. This procedure should be performed after the Diesel Particulate Filter has been replaced.
3. With the scan tool, erase all diagnostic trouble codes (DTCs).
4. With the scan tool, perform the Diesel Particulate Filter Replacement procedure located in the Engine Misc. Function section.
5. Attempt to start the vehicle.
6. If the engine is unable to start, look for any Technical Service Bulletins (TSBs) that may relate to this condition. Return to the DTC or non DTC Symptom list if necessary.
7. If the engine starts and continues to run, the repair is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.
DIFFERENTIAL PRESSURE SENSOR VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. This procedure should be performed after the Differential Pressure Sensor has been replaced.
3. With the scan tool, erase all diagnostic trouble codes (DTCs).
4. With the scan tool, perform the Differential Pressure Sensor Replacement procedure located in the Engine Misc. Function section.
5. Attempt to start the vehicle.
6. If the engine is unable to start, look for any Technical Service Bulletins (TSBs) that may relate to this condition. Return to the DTC or non DTC Symptom list if necessary.
7. If the engine starts and continues to run, the repair is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.
ROAD TEST VERIFICATION TEST
NOTE: If the battery was disconnected for any reason, you must perform the Battery Reconnection procedure in the 8F-Engine Systems section of the Service Information.
1. Inspect the vehicle to make sure that all engine components are properly installed and connected. Reassemble and reconnect components as necessary.
2. If this verification procedure is being performed after a non-DTC test, perform steps 3 and 4. If not, proceed to step 5.
3. Check to see if the initial symptom still exists. If there are no trouble codes and the symptom no longer exists, the repair was successful and testing is now complete.
4. If the initial or another symptom or DTC exists, the repair is not complete. Check all pertinent Technical Service Bulletins (TSBs) and return to the DTC List if necessary.
5. For previously read DTCs that have not been dealt with, return to the DTC or non DTC Symptom list and follow the diagnostic path for that DTC; otherwise, continue.
6. If the Engine Control Module (ECM) has been replaced, continue with step 9.
7. With the scan tool, erase all diagnostic trouble codes (DTCs), then disconnect the scan tool.
8. Turn the ignition off for at least 10 seconds.
9. If equipped with a Transfer Case Position Switch, perform step 10, otherwise, continue with step 11.
10. With the ignition switch on, place the Transfer Case Shift Lever in each gear position, stopping for 15 seconds in each position.
11. Road test the vehicle. For some of the road test, go at least 64 km/h (40 MPH). If this test is for an A/C Relay Control Circuit, drive the vehicle for at least five minutes with the A/C on.
12. At some point, stop the vehicle and turn the engine off for at least 10 seconds, then restart the engine and continue.
13. Upon completion of the road test, turn the engine off and check for DTCs with the scan tool.
14. If the repaired DTC has set again, the repair is not complete. Check for any pertinent Technical Service Bulletins (TSBs) and return to the DTC List. If there are no DTCs, the repair was successful and is now complete.
  Are any DTCs or symptoms remaining?
  
  Yes
  - Repair is not complete, perform the appropriate diagnostic procedure.
  No
  - Repair is complete.