How To Replace 7-Way On Trailer and Wiring Harness

Updated 07/26/2021 | Published 07/23/2021

Question:

Lights were working fine and suddenly failed. All of them including brakes. Bought a 7 pin connector test plug that shows everything on the truck is good. Pretty sure the connector and cable is 15 years old. It’s stiff and cracked in a few places. Should I replace it? Is it something I can do? What is the best video or text link for fixing things.

asked by: Robert P

Expert Reply:

In order to replace the trailer connector on a trailer with brakes you'll first start with the lead. Then, you'll add a junction box. The Trailer Wiring 7-Way Upgrade Kit w/ Junction Box and RV Style Connector part # 277-000141 is what I recommend because it combined the above two parts for you already. If any of the wires going from the signals and brakes are damaged you can simply run new wires using primary wire or if they are still in good shape you can reuse them and just tie into the new junction box.

I have attached an install video below but much of this will vary by application.

expert reply by: Conner L