U0140high severityNetwork
Lost Communication with Body Control Module
on 1997 Audi A3 1.6L I4 · FWD
What this code 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
Repair notes
Check for water intrusion (common BCM failure cause). Check fuses.
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Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus