Troubleshooting Brake Controller that Only Works with Manual Override Lever

Question:

I have a brake controller on my truck the problem is, they do not work correctly they will work manual when you slide the controller but not with the brake petal? I have replace the controller thinking that was the problem but that didnt fix it. kinda lost here.. help

asked by: Chris

Expert Reply:

The problem is the red wire of the brake controller. It needs to see 12 volts to know when to start applying the trailer brakes. This wire is normally connected to a brake pedal circuit which will be active when the brakes are applied and then not when they are released.

It sounds like either you have a bad connection on that wire, or more likely you have a blown third brake light fuse and the circuit is just dead. Easy way to test this is to check to see if your truck's third brake light is coming on.

expert reply by: Jameson C