U0140
NetworkModule Communicationhigh severityLost Communication with Body Control Module
What U0140 Means
Cannot communicate with the BCM.
Symptoms
- Multiple electrical features inoperative
- Lighting issues
- Lock/unlock not working
- Warning lights on
Common Causes
- BCM power failure
- CAN bus issue
- BCM failure
- Water damage
Diagnostic Steps
- Check BCM fuses
- Test power and ground
- Check CAN wiring
- Inspect for water damage
Where to start: Check for water intrusion (common BCM failure cause). Check fuses.
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