Diagnostic Test
- VERIFY DTC IS ACTIVE NOTE: Ensure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.
- 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
- With the scan tool, read all 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 FCM IS ACTIVE ON THE BUS
- Turn the ignition on.
- With the scan tool, select System select.
- Verify that the FCM is active on the bus (not grayed out).
Q: Is the FCM 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
- With the scan tool, select Special function.
- Select all DTCs.
Q: Is there more than one module with active DTCs "Logged Against" the FCM?
Yes :
- Replace/update the Front Control Module 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 this DTC in accordance with the service information
- Perform the appropriate VERIFICATION TEST.