Lost Communication with Trailer Hitch Module
2019-2019 Buick Enclave 3.6L V6
The 2019 Buick Enclave is equipped with a 3.6L V6 engine. Below you'll find detailed u0243 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
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
Repair Notes
Check fuses and trailer connector. Corrosion at trailer plug is the most common cause.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0006High Speed CAN Communication Bus (-) Open
- U0007High Speed CAN Communication Bus (-) Low
- U0008High Speed CAN Communication Bus (-) High
- U0009High Speed CAN Communication Bus Shorted Together
- U0010Medium Speed CAN Communication Bus
U0243 on Other Vehicles
Common Questions
What does code U0243 mean on a 2019-2019 Buick Enclave?
U0243 stands for "Lost Communication with Trailer Hitch Module". Cannot communicate with the integrated trailer hitch control module.
What are the symptoms of U0243 on a Buick Enclave?
Common symptoms of U0243 include: Trailer lights not working, Trailer brake output disabled, Tow/haul mode limited, Trailer sway control disabled.
What causes U0243 on a 2019-2019 Buick Enclave?
Common causes of U0243 include: Hitch module failure, CAN bus wiring, Module power loss, Fuse blown, Trailer connector corrosion.
Last updated: March 2026