Troubleshooting Trailer Brakes Only Work With Trailer Coupler Disconnected

Question:

With trailer unhooked from the ball of the truck the trailer brakes work but when you the trailer down on the ball my tekonsha controller says output shorted no brakes

asked by: Jonnie C

Expert Reply:

More than likely you have an actual short or something is loose. There should be no correlation between the trailer being hooked up to the ball mount of your truck and the trailer brakes. The only thing that really makes any sense is that there is a difference in angles between the two and it is enough for wiring to be in a different position triggering the error when lowered on the ball.

Double check your trailer connectors and make sure they aren't damaged and the wiring is secure. Also, make sure your ground connection is secure. If both of those check out I would start at the connector and work my way back looking for a short. You could also just run a new wire using # 10-1-1.

expert reply by: Robin H