Troubleshooting Prodigy Brake Controller that Shows NC When Trailer Is Connected

Question:

When I checked the trailer wheel bearings I found that the wires to one magnet were cut. I repaired them and tried to test them. When I plugged in the controller, with no trailer connected, the display had two dots and nc flashing for about 10 seconds. Now only the two dots are on. If I press the boost button b1, b2 shows on the display. I activate the slide n.c. displays. This does not change when the trailer is connected. I have 12v on the black wire and power to the red wire when I press the brake pedal and an output on the blue wire when I press the slide or brake pedal. Can you give me any advice, thank you.

asked by: Colin M

Helpful Expert Reply:

Your P2 # 90885 is acting like it does not sense a trailer connection. Somehow between the controller and the brake magnets the circuit is interrupted. Typically this is due to corrosion on pins of the trailer connector so that would be the first thing I would check. If one of the brake magnet wires was cut it's very possible that the circuit is damaged in other areas as well. Basically you have to go over all of the wiring looking for anything that would cause a short and fix as needed.

expert reply by: Jameson C