Troubleshooting Trailer Wiring Where Blinkers Operate Backwards and Some Assemblies Dont Come On

Updated 07/12/2017 | Published 07/11/2017

Question:

They wouldnt work so I changed out my harness and connected the wires. White to the ground, the split brown and yellow to the split wire running on the right side of the trailer. I connected the left split wires to the green and brown wire s on the harness. Everything came on, I was thrilled beyond belief but noticed that my right blinker on my car was turning on the left blinker on the trailer so I thought easy fix, Ill just switch the wires. I did, and now only the left blinker comes on and its controlled with the car right blinker. I have switch ed and switch and cant get all lights to come on again. Can you tell me why. Do I need to recut my wires and start fresh again. I checked my ground on the right tail light and its screwed on tight.

asked by: Judy N

Expert Reply:

What you described sounds like a combination of a weak grounds for the lights and backwards wiring.

For the assemblies that won't turn on try finding a way to improve the grounds. You can do this by running the wire back from the assembly to the main ground harness of the trailer. Then you want to make sure the correct blinker circuit is associated with the correct wire on the trailer.

Starting over with all new wire is an option, but I think just running the ground wires all back to the main ground of the trailer will fix your issue.

expert reply by: Jameson C