Network
generic / SAE
U0140
Lost Communication with Body Control Module
CAN messages from the body control module (BCM) are missing. Effects depend on what the BCM controls — typically interior lights, wipers, central locking, immobiliser handshake. On some cars the engine refuses to start because the immobiliser handshake fails.
SystemNetwork
Typegeneric / SAE
GroupU0
Range / number1 / 40
Possible causes
- BCM unpowered high
- Water ingress into BCM (often footwell-mounted) medium
- Gateway module routing CAN messages incorrectly low
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
Inspection / repair
- Difficulty: hard
- DIY: shop recommended
- Estimated cost: 100–1800 €
- Estimated time: 1–6 h
- Component: body control module
- Component: can bus wiring
- MIL / check engine light
Sources
References
sae:J2012