Troubleshooting 2019 Nissan Frontier Trailer Wiring that Stopped Working After Cutting Wires

Question:

My trailer lights stopped working after the wiring connector got pinched by the tongue and three of the four wires were severed. After splicing the wires, the lights still don’t work. I’ve checked the trailer and the circuits are good, so the problem is with the truck. I have the # C56225 wiring harness. This harness has relays, could they be the problem? How could I tell? Do I need to replace all three?

asked by: Gary D

Helpful Expert Reply:

It's possible all of the relays were blown if all of the circuits stopped working which we offer a kit for that with the part # C57000. Or if it's just the blue relays it would be part # C57000. I would recommend checking the pins of your 4-way for voltage when the trailer taillight circuits are applied like with a tester like # PTW2993. This will let you know for sure if the trailer is the problem.

I also attached a help article on troubleshooting trailer wiring as well.

expert reply by: Jameson C