Troubleshooting Prodigy P3 Brake Controller That Reads N.C. With Trailer Hooked Up

Question:

2009 f150 tow vehicle. while pulling into driveway, trailer brakes locked up. powered thru and brakes finally released. now when hooked up, controller says n.c. not connected, i assume and no trailer brakes. I checked trailer breakaway switch and brakes work when pulled. I put new plug on trailer cord end. no change. any idea where problem is?

asked by: Rob S

Helpful Expert Reply:

From what you have said, it sounds like the wiring on your trailer side should be working alright, especially if you just replaced the wiring harness. So what we need to do is see if there is anything going on with the wiring on your 2009 Ford F-150.

What you will need to do is test the 7-Way wiring harness at the back of your F-150. You can use a circuit tester, like part # PTW2993, to do that. Be sure to have somebody step on the brakes while you are testing it as well to make sure that your brake controller is sending the signal to the correct pin. The pin on your 7-Way that should have the brake controller signal on it should be the pin in the 5 o'clock position.

If you are not getting a signal at the 7-Way from your Prodigy P3 #90195, then you will want to find the blue cord inside your cab that connects to the brake controller and cut it about 6 inches from the brake controller. Once you do that you can test the brake controller signal from that point. If you don't get a signal then that means either your adapter, part # 22292, is malfunctioning and you need to replace it, or you need to replace your brake controller.

If you are getting a signal then you will need to check the blue wire from your brake controller to your 7-Way for any places that are cut, corroded, bent, or have exposed wiring, and replace it using the 10 Gauge Wire # 10-1-1. If you can't find any place where the wire looks damaged then you will need to run new 10 Gauge Wire # 10-1-1 from your brake controller to your 7-Way.

If you test your 7-Way on your F-150 and you are getting a signal, then the problem is on your trailer side. You will want to inspect the wiring on your trailer for any cut, corroded, bent, or exposed wiring. Even though you replaced your plug, there might be someplace where the wiring isn't secure so I would check that as well.

Your problem should be with the wiring somewhere along the line. If, for some reason, you have check all of the wiring and everything is getting a good strong signal yet the brake controller is still reading that a trailer is not connected, then you will need to take it to a qualified technician who can help you to troubleshoot it further.

I have attached a helpful article and some demonstration videos for you to check out as well.