Trailer Running Lights Not Working After Installing New Light and Also Trying to Reuse Old Light

Question:

today 5-7-15 i replaced a running light that i brought from etrailers -got it in the mail hooked it up and all was working i went to reconnect old light back to see if it would work it did but then went out hooked the new one back and now no running lights -what do i do i figured it is a groung wire some wheres could it be the old yellow marking light shorted it out some wheres.

asked by: Harry

Expert Reply:

It does sound like a short or a ground issue. Check the trailer wiring for any pinched or damaged wires and repair as needed.

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.

If all of the trailer running lights are not working then it could also be a blown fuse on the tow vehicle. Use the owners manual to locate all fuses related to the tow package wiring to check them.

expert reply by: Michael H