Troubleshooting Brake Controller Not Responding to Brake Pedal

Question:

I have a p3 with harness made for my 2006 2500 sierra Everything worked for the past year and today Im not getting power from under dash connector to the controller...manually i can activate brake but not with pedal Is there a fuse for the red wire under dash connector Not sure why it stopped working suddenly,makes me think it was a fuse

asked by: Emil M

Expert Reply:

Since you are getting the manual override function of your Prodigy P3 # 90195 we know you are getting power to the controller and from it. The red wire as you stated is the issue and there is not a fuse on that wire as it is on the cold side of the brake light switch. I recommend using a circuit tester like # PTW2993 to check that wiring for function. You may have a bad switch or you may have a problem inside the controller. Testing the wiring will help you discern which is the issue.

expert reply by: Jason S