Diagnostic Test
WARNING: This page is about a different car, the 2014 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
- VERIFY DTC IS ACTIVE NOTE:
Make sure the battery voltage is between 9 and 16 volts before proceeding.
- With the scan tool, read active DTCs.
Is this DTC active?
Yes
- Go To 2
No
- Refer to DIAGNOSIS AND TESTING and perform the STORED LOST COMMUNICATION DTC diagnostic procedure.
- With the scan tool, read active DTCs.
- CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS
- With the scan tool, read active DTCs from all modules.NOTE:
Check for BCM configuration, Bus hardware electrical issues, VIN Missing/Mismatch, battery or ignition related DTCs.
Does the scan tool display any active DTCs to the conditions listed above?
Yes
- Go to and perform the appropriate diagnostic procedure.
No
- Go To 3
- With the scan tool, read active DTCs from all modules.
- VERIFY THE HVAC IS ACTIVE ON THE BUS
- Turn the ignition on.
- With the scan tool, verify the HVAC is active on the bus.
Is the HVAC active on the bus?
Yes
- Go To 4
No
- Refer to DIAGNOSIS AND TESTING and perform the NO RESPONSE FROM HVAC diagnostic procedure.
- CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
- With the scan tool, read all the DTCs.
Is there more than one module with active DTCs "Logged Against" the HVAC?
Yes
- Replace/update the HVAC Module in accordance with the Service Information. Refer to CONTROL, A/C AND HEATER, REMOVAL .
- Perform the appropriate verification test for the module. If there is no verification test for the associated module perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 5
- With the scan tool, read all the DTCs.
- CLEAR DTC IN MODULE SETTING FAULT
- With the scan tool, select the module setting the DTC against the HVAC.
- Clear active DTCs.
Is this DTC still active?
Yes
- Replace/update the module that set this DTC in accordance with the Service Information.
- Perform the appropriate verification test for the module being replaced. If there is no verification test for the associated module, perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- The condition is 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 appropriate verification test for the module. If there is no verification test for the associated module, perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .