Trailer Brakes Only Work with Manual Override on Voyager Brake Controller in 2008 Ford F-150

Question:

I have a F150 FX4 and bought the Tekonsha Voyager Trailer Brake Controller - 1 to 4 Axles - Proportional and wired it with the harness that came with it for that controller and the truck. Supposed to be plug and play. Well everything works, lights, turn signals but when I hit the brakes the trailer brakes do not activate. If I use the slide on the controller the brakes work. Any idea? Any idea which wire is the wire for the pedal so I could tap into that one to make the brakes work from the pedal?

asked by: Chris

Expert Reply:

When the trailer brakes do not work with the brake pedal but work fine with the manual override that usually indicates a problem on the red wire on the brake controller. The red wire is the input circuit to the brake controller that sense when you step on the brakes.

Common causes for issues on the red wire include a blown stop light or CHMSL fuse. Check the owner's manual to find the locations of these fuses and replace them as needed. It may also be that the red wire is in the wrong place on the vehicle side.

The wiring harness you should be using with the brake controller and your 2008 Ford F-150 is # 3035-P. Make sure that it is wired the same as the picture I have included on the vehicle side. If the red wire is not in the same location, you will need to move so it matches the picture.

You might be able to tap into the brake switch. In order to find the correct wire on the brake switch, located above the brake pedal, you will need to use a circuit tester, # PTW2993 if you need one, and test the wires. You need the wire that only shows power when you step on the brake pedal. If it shows power with the headlights on or turn signals on, then it is not the correct wire. It is possibly a light green wire on the brake switch so try that one first.

expert reply by: Michael H