Troubleshooting Shorted Out Brake Controller Connected to Breakaway System

Updated 05/29/2018 | Published 05/25/2018

Question:

Hello, Hooked up my truck to our 24foot Carson enclosed trailer that we just installed a new breakaway battery on. Immediately fried the controller. Short to ground somewhere in the harness? Thank you

asked by: Jeremiah H

Expert Reply:

I'm sorry that this happened to your brake controller. I am happy to do research to help get this issues resolved.

If when testing the breakaway system and the pin was pulled with the battery connected backwards. This would compromise the brake controller. When reaching out to my contact at Tekonsha we agreed that there may be a wiring issue someplace in the breakaway system. The combination of the wiring issue, combined with pulling the pin would certainly cause frying of the brake controller.

The break away system on a trailer would typically have its own battery, like that shown with part # 20400. The break away switch should be wired so that it is a normally open circuit that closes when the pin is pulled. When the pin is pulled, the circuit closes, allowing voltage to travel to the trailer brakes. One leg of the switch should be wired to the positive terminal of the break away battery, and the other leg tapped into the brake circuit (see provided diagram.)

Once you have everything wired as shown in the diagram, the system should work fine for you.

expert reply by: Timothy G