Troubleshooting Trailer Wiring Not Lighting Up After Rewiring Trailer

Question:

im trying to re place old wires the old light works so i cut the wires and i got a 2 wire black and red i can put on a battery works fine ,but try to tye togeather on rv wires it want come on ,just dont get it

asked by: Randy D

Expert Reply:

If your RV wiring doesn't want to power the lights that means the issue is either the ground or the power since you have verified the lights work. You would want to use a circuit tester like part # PTW2993 to test the wires of the trailer with the correct taillight function on to determine which is the power wire and wire it accordingly to the lights of your trailer.

If that still doesn't activate the light then the issue is the ground wire. In that case you need to improve the ground by either finding a better grounding point for the wire or just running the wire all the way back to the main ground circuit of the trailer wiring.

expert reply by: Jameson C