Why Do Trailer Brakes Activate Upon Connecting Trailer When Using a 5504 Brake Controller

Updated 04/05/2010 | Published 04/03/2010

Question:

Why do my trailer brakes come on as soon as Ihook up my trailer? I double checked all of my wiring and it all seems to look good.

asked by: Jon

Expert Reply:

If your brakes are coming on as soon as you plug in the trailer, the issue is most likely that the red stop light wire going into the brake controller is connected at the wrong location.

The stop light wire should be connected to the wire coming off your brake pedal that gets power when the pedal is pressed, and no power when the pedal is released.

You can also check on the trailer side to make sure that the electric brake wire is not connected to a 12v output wire.

Another possibility, if you have a breakaway kit installed, would be that the breakaway function has been activated and you would just need to correct this.

I would be glad to try and make some definite suggestions for you if you could provide the year, make, and model of your vehicle.

You can view a little more information on wiring for a brake controller at the link provided.

expert reply by: Sarah L