U2178
Lost Communication With Trailer Interface Control Module
U2178 is an OBD-II diagnostic trouble code meaning: Lost Communication With Trailer Interface Control Module. Common causes: broken or damaged wiring to the trailer module, short circuit in trailer circuit. Estimated repair cost: $28–167.
Symptoms
- No power at trailer socket
- Turn signals on trailer not working
- Trailer brake lights do not work
- Error message on the dashboard
- The trailer is not recognized by the vehicle system
Causes
- Broken or damaged wiring to the trailer module
- Short circuit in trailer circuit
- Trailer control module malfunction
- Poor contact in connectors
- Problems with the car's main ECU
How to Fix
- Check the integrity of the wiring to the trailer module
- Check fuses associated with the trailer system
- Inspect connectors for corrosion or damage
- Check the power and ground of the trailer module
- If necessary, replace the trailer control module
Related codes
FAQ
What does the U2178 code mean?
U2178 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Trailer Interface Control Module
What causes a U2178 error code?
The most common causes of U2178 include: Broken or damaged wiring to the trailer module; Short circuit in trailer circuit; Trailer control module malfunction; Poor contact in connectors.
How do I fix a U2178 diagnostic trouble code?
To fix U2178: Check the integrity of the wiring to the trailer module. Check fuses associated with the trailer system. Inspect connectors for corrosion or damage. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U2178?
Yes, but get it checked soon
How much does it cost to fix U2178?
The estimated repair cost for U2178 is $28–167. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat