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
NOTE:
After the wiring harness is repaired, or the Ambient Air Temperature (AAT) Sensor is replaced, the vehicle MUST be operated for at least five minutes, at above 15 mph (24 km/h). If this is not performed, the AAT Sensor data in the BCM will NOT be updated and may lead to the incorrect replacement of the BCM.
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 AMBIENT AIR TEMPERATURE SENSOR
1. Turn the ignition off.
2. Disconnect the Ambient Air Temperature Sensor 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 Ambient Air Temperature Sensor in accordance with the Service Information. Refer to SENSOR, AMBIENT TEMPERATURE, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (G31) AAT SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM C6 harness connector.
3. Check the continuity between ground and the (G31) AAT Sensor Signal circuit at the Ambient Air Temperature Sensor harness connector.
  Is there continuity between ground and the (G31) AAT Sensor Signal circuit?
  
  Yes
  - Repair the short to ground in the (G31) AAT Sensor Signal circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (G31) AAT SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE (G931) SENSOR GROUND CIRCUIT
1. Check the continuity between the (G31) AAT Sensor Signal circuit and the (G931) Sensor Ground circuit at the Ambient Air Temperature Sensor harness connector.
  Is there continuity between the (G31) AAT Sensor Signal circuit and the (G931) Sensor Ground circuit?
  
  Yes
  - Repair the short between the (G31) AAT Sensor Signal circuit and the (G931) Sensor Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK RELATED 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. Reconnect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect 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.