Troubleshooting Trailer Break Away System

Updated 02/22/2012 | Published 02/17/2012

Question:

I have a question about the wiring on my trailer breakaway switch. The trailer has a winch and 12 volt battery installed in the trailer, there is no small battery tied into the breakaway wiring as i have seen on other trailers. The breakaway switch wires - one is grounded to the trailer frame, the other is spliced into the brake wire going to the trailer tires. When I test the switch the brakes to not engage.

asked by: Jim H

Expert Reply:

The break away system on a trailer would typically have its own battery, like that shown with part # 20400. The reason that pulling your break away switch does not actuate your brakes is that it is not wired correctly.

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: Mike L