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 the STORED LOST COMMUNICATION test procedure.
- 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 the DIAGNOSTIC TROUBLE CODES (DTC) LIST for a complete list of the symptoms.
No :
- Go To 3
- With the scan tool, read all active DTCs from all modules.
- VERIFY THAT THE ECM/PCM IS ACTIVE ON THE BUS
- Turn the ignition on.
- With the scan tool, select Network Diagnostics.
- Verify that the ECM/PCM is active on the bus.
Q: Is the ECM/PCM active on the bus?
Yes :
- Go To4
No :
- Refer to the NO RESPONSE test procedure.
- CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS
- With the scan tool, select Network Diagnostics.
Q: Is there more than one module with active DTCs "Logged Against" the ECM/PCM?
Yes :
- Replace/update the ECM/PCM in accordance with the service information.
- Perform the appropriate VERIFICATION TEST.
No :
- Replace/update the module that set this DTC in accordance with the service information.
- Perform the appropriate VERIFICATION TEST.