U0243
NetworkModule Communicationlow severityLost Communication with Trailer Hitch Module
What U0243 Means
Cannot communicate with the integrated trailer hitch control module.
Symptoms
- Trailer lights not working
- Trailer brake output disabled
- Tow/haul mode limited
- Trailer sway control disabled
Common Causes
- Hitch module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Trailer connector corrosion
Diagnostic Steps
- Check hitch module fuse
- Test power and ground
- Check CAN wiring
- Inspect trailer connector
- Test trailer light outputs
Where to start: Check fuses and trailer connector. Corrosion at trailer plug is the most common cause.
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