Troubleshooting Tekonsha Prodigy P2 Brake Controller Only Working with Manual Override

Updated 06/26/2020 | Published 06/22/2018

Products Featured in This Question

Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional

(2763)

$160.45

Hook Probe Circuit Tester

(60)

$13.33

Question:

Brakes work on manual control but not with pedal

asked by: Jeffrey D

Expert Reply:

When a trailer brake controller like the Tekonsha Prodigy P2 # 90885 that you mentioned only sends power to the brakes when using the manual override, and not when stepping down on the brake pedal, it is usually caused by the brake controller red wire being connected to the wrong side of the vehicle brake light switch.

I recommend using a circuit tester like # PTW2993 to test the wires above the brake pedal to make sure you are connected to the correct wire. The wire you want to connect to the controller's red wire should only have power with the brake pedal depressed, and no power with any other function (such as turn signals or running lights).

If you are connected to the correct wire, then the issue might simply be how you are testing the controller. The Tekonsha Prodigy P2 is a proportional controller, meaning it will send out a specific amount of power to the trailer brakes in proportion to how fast the vehicle is moving. This means that if you are testing the controller with the vehicle sitting still, pressing down on the brake pedal isn't going to send much, if any power back to the 7-Way. This would be completely normal.

If you are still having issues, please let me know and I will be happy to help you further.

expert reply by: Chris R

Mark W.

6/23/2020

I just read this answer. My issue is that my controller was working great, but now it is not. Previously it worked with the brake pedal, I did not disconnect anything, and now it only works on manual mode. Any ideas?

Chris R.

6/26/2020

A couple things could be going on here. I would first check to make sure the red wire from the brake controller still has a good connection to the brake switch wire on the vehicle and that there aren't any pinched or exposed sections. If you used a plug-in harness make sure the plugs are still fully seated. If that's all good it's possible the brake light switch itself on your truck is going bad and needs to be replaced.