Prodigy P2 Brake Controller Shows NC with a Trailer Connected to a 2018 Kia Sedona

Question:

I have a 2018 Kia Sedona that had factory 4 pin trailer wiring in it. I had a Prodigy P2 Brake controller and 7 pin wiring harness installed after market. The first time I towed my trailer there was no problems, however on my last trip coming home the brake controller was flashing .nc. even thought the trailer was hooked up and all the lights and blinkers working. Before this trip when ever I drove the van the brake controller would show the braking level even when not towing. Now when I start the van with no trailer it shows the braking level for about 10 seconds, and I can even use the manual lever and it displays braking level up to 11 but then flashes the .nc. again. Could there be a short in the wiring coming out of the controller at the connection to the brake wire in the van or a loose connection at the battery?

asked by: David

Expert Reply:

It sounds like you have a short and possibly a loose or damaged connection somewhere. A short like this is usually caused by corrosion in a trailer connector or a pinched or damaged wire. I do also recommend changing the white wire ground location from the aftermarket 7-Way to a different bare metal surface (to cover all our bases).

Make sure that the 7-Way connector is clean and free of corrosion inside, where the wires attach, and outside on the pins. Check the wiring as best as you can, especially the blue wire at the back of the 7-Way, and fix any pinched or damaged wires. The brake controller # 90885 itself should be ground to the negative battery terminal on your 2018 Kia Sedona. No other ground location is sufficient.

I have included some additional links on testing and troubleshooting brake controllers for you.

expert reply by: Michael H