U064D

Lost Communication With Trailer Brake Control Switch

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$17–56 (est.)

Symptoms

Error message on the dashboard
Trailer brakes do not work
Brake system warning light
No response when pressing trailer brake switch

Causes

Open or short circuit in the switch circuit
Trailer brake switch malfunction
Problems with trailer wiring harness
Malfunction of the trailer brake control unit
Poor contact in system connectors

How to Fix

Check the continuity of the trailer brake switch circuit
Test the operation of the trailer brake switch
Inspect the wiring harness and connectors for damage.
Check power and ground in the circuit
If necessary, replace the switch or repair the wiring

Related codes

U064E U064F U0650