Lost Communication with Body Control Module A
A second body control module (BCM "A") has dropped off the bus. Several comfort, lighting and locking functions stop working until the BCM is back online.
Affected components
- Body control module
- Can bus wiring
Common causes
- High likelihood: BCM A unpowered
- Medium likelihood: CAN wiring to BCM A broken
- Low likelihood: Gateway module routing CAN messages incorrectly
Possible symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.