Lost Communication With Trailer Brake Control Module
What does U0197 mean?
The U0197 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Trailer Brake Control Module. This is a moderate severity code.
Common Symptoms
- Trailer brake controller not functioning
- Trailer brake warning light on
- No braking force applied to trailer
- Trailer sway control inoperative
- Integrated trailer brake display shows error
Probable Causes (Ranked by Likelihood)
- Failed integrated trailer brake control module Very High
- Damaged trailer wiring harness or connector High
- Corroded trailer plug connector Moderate
- Aftermarket brake controller interfering with factory system Low
Step-by-Step Diagnostic Procedure
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Inspect the trailer connector plug for corrosion or damage
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Check the trailer brake controller fuse
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Verify the trailer wiring harness at the hitch receiver
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Test the system with a trailer brake simulator
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Check for aftermarket controllers conflicting with factory system
Frequently Asked Questions
Can I drive with code U0197?
Yes, but do not tow a trailer until the trailer brake system is repaired. Towing without trailer brakes is dangerous and may be illegal.
What causes U0197?
Most commonly a corroded trailer plug connector or failed integrated trailer brake controller. Regular trailer plug maintenance can prevent this issue.
Is U0197 expensive to fix?
Typically $100 to $600. Cleaning or replacing the trailer connector is inexpensive. Module replacement is more costly but less common.