Troubleshooting an LED Trailer Light Staying On When Vehicle is Turned Off

Published 12/12/2011

Products Featured in This Question

Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(180)

$66.84

Hook Probe Circuit Tester

(62)

$13.94

Question:

I have an Escape 2012 and a Grand Caravan 2010 and both have a Curt wire harness installed. When any of my vehicle is connect on my trailer, and the engine is off, the middle LED light on my trailer will stay on just a small light. Whys that?

asked by: Guy W

Expert Reply:

This can occur with some Curt wiring harnesses. On a trailer with LED lights the lights may be dimly lit when the vehicle is off because the harness has a direct connection to the battery and there is some power to the 4-Way all the time.

If the lights are coming on as bright as normal the first thing, I would check would be the 4-way trailer connector that is on your both of your vehicles. It sounds like the problem is in your trailer, but it is still a good idea to rule out the vehicles from the equation. You will want to use a circuit tester like our part # PTW2993 and test for voltage on all of the circuits of the 4-way when your vehicles are off to determine if there is any voltage coming from any of the circuits. If so, then you know the problem lies on the vehicle side of the equation.

The next thing I would do is connect your trailer with your vehicle off so that the middle LED that is giving you problems is on. Next, you will want to check the wiring for the LED using a circuit tester like our part # 40376 and trace the wiring of the LED testing for voltage frequently until you find out where the problem area is.

I attached an FAQ on trailer wiring and a review video for the # 40376 for you to check out also.

expert reply by: Jameson C