Is Short on Prodigy P2 on Truck or Trailer

Question:

Hello, i bought the Tekonsha brake controller and hooked it up to my 2002 F250. I connected a 7 way tester to the terminal and the brake test light flashes on once every few seconds. When I hook up the trailer, I am getting the S.H. error so it looks like there is a short somewhere. with the test light flashing on and off, does that mean the short is in my truck? There is no error code until i hook up the trailer. Just looking for ideas of where to start my search for the short.

asked by: Michael M

Expert Reply:

The Prodigy P2, part # 90885, along with other brake controllers, send back a small signal on the brake output circuit to the 7-way in order to check for a trailer. It's like a low voltage pulse. This sounds like what you're getting on your light tester to me. So I'm thinking your problem is on the trailer side. In addition to that wiring issues are more typically found on the trailer than on the truck.

To test a little further have someone engage the manual override lever on the P2 while you're testing the brake pin. For the record the correct pin on your 7-way should be the 4 O'clock pin but it sounds like you already know this. If the P2 operates normally in this case then it reinforces the idea that the issue is on the trailer side. Make sure they're using the manual override and not the brake pedal because proportional controllers, like the P2, won't send back power unless the truck is in motion if you're using the brake pedal.

To check the trailer start by inspecting and cleaning its 7-way. It could be that easy. If not then your only option is to start tracing the wires looking for any exposed, damaged, or pinch points and repair as needed.

expert reply by: Charles S