Trailer Lights Will Not Turn On But there is Power at the Vehicle Trailer Connector

Question:

My trailer lights dont turn on. But the adapter does lit. I replaced the lights installed onlyrics one to see if tat was the problem but it still doesnt work.

asked by: Daniel

Expert Reply:

This sounds like a ground issue especially since the adapter you mentioned is lit. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light but can show up any time.

Make sure that the vehicle side and trailer side connectors, including the adapter, are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces.

The light grounds should also be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

expert reply by: Michael H