Both Trailer Turn Signals Blink Instead of Just One

Question:

Both signal lights work when only wanting right or left signal light to work?

asked by: James M

Expert Reply:

This sounds like a potential ground issue. Weird things can happen when there is a ground problem.

Make sure that the vehicle side and trailer side connectors are clean and free of corrosion inside and out. A short from one of the turn signal/brake light circuits to the other could cause this issue. 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