Troubleshooting Tekonsha P3 Brake Controller that Constantly Shows Braking Output Reading

Updated 11/10/2021 | Published 05/17/2018

Question:

This season I have been having an issue with my Tekonsha P3 brake controller, I did not notice this last year. Everything seems normal while I am braking, however when I let off the brakes instead of returning to 0.0 it will often stay at 0.6 or 0.8, etc. Some time it will even increase from there. Similarly, when I am stopped at a light/sign and then accelerate, the brakes will often stay on not locked up often in the 2 - 4 range which is obviously very noticeable. To get the controller to return to 0.0, I simply tap the brake pedal gently and it will return to zero. Also, the controller will occasionally jump up when I hit a bump. Any thoughts? Is this a truck side brake sensor issue 2007 Suburban 2500? Thank you!

asked by: Matthew B

Expert Reply:

The issue is the red wire of yoru brake controller. It's only supposed to see voltage when the brakes are applied which then tells the P3 # 90195 to start looking for deceleration and apply proportional braking power. If there is a short on this circuit and there is voltage on it all the time the controller is basically active all the time and will apply the trailer brakes with any change in inertia.

So what you'll want to do is check the red wire of your brake controller for a short to the black wire of the controller and fix as needed and you'll be set.

expert reply by: Jameson C

Tanner B.

11/8/2021

Did you find a solution? I am having the same issue with my 07 Silverado 2500. I am showing output voltage as soon as I turn the key, even with the trailer disconnected. I double checked all the wiring connections and everything looks good. I am stumped.

Les D.

11/10/2021

I would follow the advise of the question you commented on, which read; The issue is the red wire of your brake controller. It's only supposed to see voltage when the brakes are applied which then tells the P3 # 90195 to start looking for deceleration and apply proportional braking power. If there is a short on this circuit and there is voltage on it all the time the controller is basically active all the time and will apply the trailer brakes with any change in inertia. So what you'll want to do is check the red wire of your brake controller for a short to the black wire of the controller and fix as needed and you'll be set. If this test fails you will need a replacement controller.