Trailer Running Light Issue
I have a 5th wheel horse trailer with some kind of light/wiring issue and I'm hoping someone can help me debug this. On an earlier trip, we didn't have the rear running lights showing on the back o...
Forum Discussion
First thing I would do is get under and look at the routing of wires. If like many the marker wires branch off the taillight wire, that would be a connection to check.
All trailer lights should have a wire to carry the ground to at least frame of tow vehicle. Marker lights need 2 wires, and tail/turn should have 3 wires to fixtures (Note to OP. Most trailers built to be towed behind light vehicles don't have brake lights. When you brake works, that circuit is for the E brakes. To signal a stop, send power to both turn lights)
Most light manufacturers of light duty trailers still use the trailer frame for ground. They have a wire on the cord connected to frame, and wires from lights, or worse, depend on body contact to frame, as a ground path. IMHO, a much better plan is run the ground side just like the power side, and keep the frame above ground.
All trailer lights should have a wire to carry the ground to at least frame of tow vehicle. Marker lights need 2 wires, and tail/turn should have 3 wires to fixtures (Note to OP. Most trailers built to be towed behind light vehicles don't have brake lights. When you brake works, that circuit is for the E brakes. To signal a stop, send power to both turn lights)
Most light manufacturers of light duty trailers still use the trailer frame for ground. They have a wire on the cord connected to frame, and wires from lights, or worse, depend on body contact to frame, as a ground path. IMHO, a much better plan is run the ground side just like the power side, and keep the frame above ground.
