CC-ID-423moderate severityBody
Trailer Coupling Lock
on 2021 BMW i3 Range Extender · RWD
What this code means
A fault has been detected with the trailer coupling lock or its locking status. This is raised by the towing module monitoring the coupling mechanism.
Symptoms
- Coupling lock warning displayed
- Tow bar may not lock/unlock
- Warning when using tow function
Common causes
- Coupling not fully locked
- Faulty coupling lock sensor
- Actuator or mechanism fault
- Wiring fault
Diagnostic steps
- Verify coupling is fully locked
- Check coupling lock sensor signal
- Test lock actuator operation
- Inspect wiring and connectors
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Other Body codes on this vehicle
B0001
Driver Frontal Stage 1 Deployment Control
B0002
Driver Frontal Stage 2 Deployment Control
B0003
Passenger Frontal Stage 1 Deployment Control
B0004
Passenger Frontal Stage 2 Deployment Control
B0005
Driver Knee Airbag Deployment Circuit
B0006
Passenger Knee Airbag Deployment Circuit
B0007
Rear Left Side Airbag Deployment Circuit
B0008
Rear Right Side Airbag Deployment Circuit
B0009
Rear Center Airbag Deployment Circuit
B0010
Driver Side Airbag Deployment