Should the Blue Wire of a Brake Controller have Voltage

Updated 07/18/2016 | Published 07/16/2016

Question:

No power on the blue wire under the dash to plug my trailer brake box into....have all other power to the other wires...just none to the blue wire

asked by: Larry C

Expert Reply:

The blue wire of your brake controller wiring isn't going to have voltage on it unless you have a brake controller connected to it with either the manual override lever pulled or with the brakes applied.

This is the circuit that the controller uses to carry the brake signal back to the 7-way.

I attached a couple help articles on troubleshooting brake controllers for you to check out as well.

expert reply by: Jameson C