Diagnostic Test

VERIFY DTC IS ACTIVE
NOTE: Ensure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.
1. With the scan tool, read active DTCs.
Q: Is this DTC active?

Yes :
- Go To 2
No :
- Refer to *STORED LOST COMMUNICATION DTCS .
CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS
1. With the scan tool, read active DTCs from all modules.
NOTE: Check for FCM configuration, CAN B or C hardware electrical, VIN Missing/Mismatch, battery or ignition related DTCs.

Q: Does the scan tool display any active DTCs to the conditions listed above?

Yes :
- Diagnose and repair the DTC. Refer to appropriate DTC.
No :
- Go To 3
VERIFY THAT THE HVAC IS ACTIVE ON THE BUS
1. Turn the ignition on.
2. With the scan tool, select System select.
3. Verify that the HVAC is active on the bus (not grayed out).
Q: Is the HVAC active on the bus?

Yes :
- Go To 4
No :
- Refer to the appropriate No Response test procedure in this article.
CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
1. With the scan tool, select Special function.
2. Select all DTCs.
Q: Is there more than one module with active DTCs "Logged Against" the HVAC?

Yes :
- Replace/update the A/C Heater Control in accordance with the service information.
- Perform BODY VERIFICATION TEST - VER 1 . (Refer to ELECTRONIC CONTROL MODULES/MODULE - FRONT CONTROL/DIAGNOSIS AND TESTING).
No :
- Replace/update the module that set the DTC in accordance with the service information
- Perform the appropriate VERIFICATION TEST.