Troubleshooting New Wiring And LED Lights On Trailer

Question:

Trailer LED lights....Only 2 of the led lamps are lighting up on each of the lights and the brake lights ate not working. both turn signals only two led flickering in each light. Same results on trailer tested from two different jeeps. Lights are new, wiring is new and sanded paint at 3 ground wires 2 at lamps 1 in trailer tongue. Any rhoughts....Ground issue??

asked by: Hal

Expert Reply:

The first thing I recommend is to check all of the ground locations on the trailer. If you have a ground that went bad it can cause the lights to blink and then finally fail.

If you check all of the grounds and they are connected securely to clean bare metal at each light and at the trailer coupler and your lights still do not work correctly, I would then check the vehicle side connector for proper function.

I recommend using a circuit tester, like part # PTW2993, and test the connector without the trailer attached first. You will see that the exposed terminal is ground. The terminal for the brown wire should show power when the taillights are on. The terminal for the yellow wire should show power when the left turn signal and/or brakes are on, and the terminal for the green wire should show power when the right turn signal and/or brakes are on.

If the vehicle connector is functioning properly, test the wires going into the LED taillights for proper function. If you test the wiring and find that the wires going into the lights do not work correctly then you will need to check the trailer wiring for a short. Look for broken or pinched wires on the trailer and repair as needed.

You need to keep in mind that if you are using the lights on a boat trailer you will want to make sure you have submersible lights like part # TLL9RK. If not, you can short out the lights if the trailer is connected to the truck when putting the boat in water.

I have attached links to a couple helpful articles you can check out.