Troubleshooting Trailer Brakes Only Working with Manual Override

Question:

Gentlemen I just purchased a 2013 Keystone travel trailer I had my wires from my truck hooked up brake controller and what not double checked it that it was working my problem is I have no trailer brakes when I use the pedal but I can manually use the trailer brakes off of the controller

asked by: John A

Expert Reply:

It sounds like the electric brakes on your trailer aren't working when stepping on the brake pedal but are working when using the manual override on the brake controller.

If this is the case then the first possible cause might simply be how you are testing the controller. Many trailer brake controllers are proportional, which means they power the trailer brakes based on the deceleration of the tow vehicle. If you have a proportional controller and are testing the brakes with the tow vehicle and trailer parked, the controller likely won't send enough power back to lock up the brakes when stepping on the brake pedal. The manual override sends back a max amount of power so that is why the brakes would work fine when testing them in that manner.

If that is not the issue, then you will next want to make sure you have the red wire from the brake controller connected to the cold side of the brake switch wire above the brake pedal. This is the wire that ONLY receives power with the brake pedal depressed and no power with any other function. You can use a circuit tester like # PTW2992 to ensure you are connected to the correct wire.

If this does not resolve the issue, please let me know and we can continue to troubleshoot.

expert reply by: Chris R