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.
Is this DTC active?
Yes
- Go to step 2
No
- Refer to the Stored Lost Communication test procedure. Refer to Non-DTC Diagnostics/Communication - Diagnosis and Testing .
- With the scan tool, read active DTCs.
- CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS
- With the scan tool, read all active DTCs from all modules.NOTE: Check for FDCM configuration, CAN B or C hardware electrical, VIN Missing/Mismatch, battery or ignition related DTCs.
Does the scan tool display any active DTCs to the conditions listed above?
Yes
- Diagnose and repair the DTC. Refer to the Table of Contents for a complete list of the symptoms.
No
- Go to step 3
- With the scan tool, read all active DTCs from all modules.
- VERIFY THAT THE FCM IS ACTIVE ON THE BUS
- Turn the ignition on.
- With the scan tool, select Network Diagnostics.
- Verify that the FCM is active on the bus.
Is the FCM active on the bus?
Yes
- Go to step 4
No
- Refer to the no response test procedure. Refer to Non-DTC Diagnostics/Communication - Diagnosis and Testing .
- CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
- With the scan tool, select Network Diagnostics.
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. Refer to DTC-Based Diagnostics/MODULE, Front Control (FCM) - Standard Procedure .
No
- Replace the Anti-Lock Brake Module in accordance with the service information
- Perform ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
- With the scan tool, select Network Diagnostics.