How To Determine The Correct Brake Signal Wire When Installing A Brake Controller

Updated 06/16/2017 | Published 06/15/2017

Question:

Looking to find out which wire to tap onto for the brake controller signal wire. Do you have a wiring diagram or knowledge of which one. Or a photo?

asked by: Ryan

Expert Reply:

Unfortunately we do not have access to the correct brake signal wire you will need to use for a brake controller installation on a 2015 Subaru XV Crosstrek. However, I do have a way that will allow you find this fairly easy.

In order to find the correct brake signal wire behind the dash on your vehicle, you will need a circuit tester like part # PTW2993. Once acquired, you will need to depress the brake pedal and test each of the wires running to the brake pedal in order to determine which wire only illuminates when the pedal is pressed. This will be the correct brake signal wire you will need to hook the brake controller to.

I have attached a brake controller wiring troubleshooting article for your review that covers testing the stop light switch wires.

expert reply by: Conner L