Troubleshooting Trailer Wiring that Stops Working When Headlights Are On
Updated 12/06/2016 | Published 12/05/2016
Question:
94 ford explorer. I have a plug and play t harness by curt Everything works until I turn on the head lights. Wjen I hit a signal all the trailer lights blink. If I hit the break everything turns off until I release the break
asked by: Jacob
Expert Reply:
Try improving the connection of the main ground wire of the trailer wiring harness. Make sure it is attached to a clean metal surface. Or you can run all of the trailer wires back to the main ground. This is actually the ideal solution. But you can also check the current grounds for the lights to make sure they are making a solid connection to a clean metal surface.
What you described is the classic insufficient ground scenario so finding a way to improve the grounds will fix the problem.
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