Trailer Right Blinker and Brake Light Not Working when Connected to a 2015 Ram 2500

Question:

Hooked up travel trailer and no running lights and no right brake or blinker light. but brake light and blinker work on left/driver side. Installed new headache rack that has lights and a wiring harness and the harness plugs in to the trailer plug and the factory plug plugs into the new harness. But same issue no running lights and no right blinker or brake light but have blinker and brake light on left/driver side and also have backup lights. On both sides. Checked fuses but all look good.

asked by: Travis

Expert Reply:

The issue you are describing sounds like a ground issue. 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 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.

It also could be something as simple as a burned out bulb or a tow package fuse. I know you mentioned checking the fuses but often times the tow package fuses are separate from the corresponding light fuses for the truck.

expert reply by: Michael H