Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Body Control Module (BCM) DTCs and record on the repair order.
2. Record the Environmental Data and any DTCs.
3. With the scan tool, erase DTCs.
4. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
5. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE HUMIDITY SENSOR MODULE FOR AN INTERNAL SHORT
1. Turn the ignition off.
2. Disconnect the Humidity Sensor Module harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
6. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 3
  No
  - Replace the Humidity Sensor Module in accordance with the Service Information. Refer to SENSOR, HUMIDITY, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE INTERIOR REAR VIEW MIRROR FOR AN INTERNAL SHORT
1. Turn the ignition off.
2. Disconnect the Inside Rear View Mirror harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
6. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 4
  No
  - Replace the Inside Rear View Mirror in accordance with the Service Information. Refer to MODULE, COMBINED REAR VIEW MIRROR, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE TERRAIN SWITCH BANK MODULE (TSBM) FOR AN INTERNAL SHORT
1. Turn the ignition off.
2. Disconnect the TSBM harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
6. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 5
  No
  - Replace the Terrain Switch Bank Module (TSBM) in accordance with the Service Information. Refer to SWITCH, TERRAIN SELECT, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE AUXILIARY SWITCH BANK MODULE FOR AN INTERNAL SHORT
1. Turn the ignition off.
2. Disconnect the Auxiliary Switch Bank Module harness connector.
3. Turn the ignition on.
4. With the scan tool, erase DTCs.
5. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
6. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 6
  No
  - Replace the Auxiliary Switch Bank Module in accordance with the Service Information. (Refer to POD, SWITCH ).
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (D404) LIN BUS 4 CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Body Control Module (BCM) C8 harness connector.
3. Check for continuity between ground and the (D404) LIN Bus 4 circuit at the BCM C8 harness connector.
  Is there continuity between ground and the (D404) LIN Bus 4 circuit?
  
  Yes
  - Repair the short to ground in the (D404) LIN Bus 4 circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 7
CHECK RELATED BCM HARNESS CONNECTIONS
1. Disconnect all BCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  - Test complete.