Troubleshooting Prodigy P2 Trailer Brake Controller with N.C. Code With Trailer Connected

Published 06/03/2020

Question:

P2 brake controller N.C. code. ~ 2003 Dodge Ram 1500 RV Dealer installed with factory harness. Black wire hot, red wire power with brake pedal blue wire power at 7way plug when brakes applied. New 2020 Forest River Trailer, duel axel. Brakes very aggressive, at times will lock up. I can not adjust down the gain on controller when using manual leaver because controller only displays N.C. code. Controller will go into B1. B2. B3. and R. But like I said no way to adjust down the power. ? Also used test light at truck 7 way plug. Test light came on with brake pedal and or manual knob while probing blue 5 oclock and white ground 7 oclock , yet controller still showed N.C. Thought the light would have enough resistance to make complete circuit, and to have controller show .C. connected, but controller only showed . 1 dot when using brake pedal and showed N.C. with manual leaver Thanks, T. Jones

asked by: Tim J

Helpful Expert Reply:

It sounds like the Prodigy P2 # 90885 is connected correctly under the dash. The N.C code means it doesn't see a draw on the brake output pin at the 5'oclock position so it doesn't see a trailer connected. The dial on the left top of the controller is the gain controller and should allow you to adjust the output coming from the controller.

When you put the test light on the pin, and hit just the brake pedal, there should not have been any light because you weren't moving. It should only light when you hit the manual override. It sounds like you have a bad controller because the inertia sensor inside it is malfunctioning. If you are using an LED circuit tester light, you may get a false reading because it requires so minimal a power to light where an incandescent tester would show brightness differences with increased power levels.

I've attached an article to help bench test your trailer brake controller.

expert reply by: Jason S