U0438
Invalid Data Received From Trailer Brake Control Module
U0438 is an OBD-II diagnostic trouble code meaning: Invalid Data Received From Trailer Brake Control Module. Common causes: trailer brake control module malfunction, damage to the wiring harness to the trailer module. Estimated repair cost: $56–167.
Symptoms
- Check Engine light comes on
- No response from trailer brakes
- Incorrect operation of trailer brakes
- Errors in the braking system on the dashboard
Causes
- Trailer brake control module malfunction
- Damage to the wiring harness to the trailer module
- Poor contact in connectors
- Software error in trailer module
- Problems with power supply to the trailer module
How to Fix
- Check the integrity of the wiring harness to the trailer module
- Inspect and clean the connector contacts
- Check the power and ground of the trailer module
- Test or replace trailer brake control module
- Update trailer module software
Related codes
Error U0438 by Vehicle Brand
FAQ
What does the U0438 code mean?
U0438 is an OBD-II diagnostic trouble code that indicates: Invalid Data Received From Trailer Brake Control Module
What causes a U0438 error code?
The most common causes of U0438 include: Trailer brake control module malfunction; Damage to the wiring harness to the trailer module; Poor contact in connectors; Software error in trailer module.
How do I fix a U0438 diagnostic trouble code?
To fix U0438: Check the integrity of the wiring harness to the trailer module. Inspect and clean the connector contacts. Check the power and ground of the trailer module. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U0438?
Do not drive — repair immediately
How much does it cost to fix U0438?
The estimated repair cost for U0438 is $56–167. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat