LED Indicator Stays On All the Time When Trailer is Plugged Into 7 to 4-Way Adapter 47345

Updated 02/20/2024 | Published 02/08/2014

Question:

When I plug this adapeter into my vehicle, it works great! The tail light LED stays solid and the R and L LEDs blink when the proper turn signal is on. This would indicate that the vehicle wiring is working. However, when I plug my trailer into this adapter the R LED stays solid. What does this mean? I am having trouble with my trailer wiring...the right tailight doesnt work. The left tailight and running lights work well. Does this solid LED indicate a problem with the trailer wiring or my vehicle wiring?

asked by: Dave

Expert Reply:

If the LED light is staying on that indicates that power is being drawn through the system. This indicates a short on the trailer wiring. To track down the short there are a couple of things you can do.

First, make sure the trailer side connector is clean and free of corrosion. Then make sure its main ground is attached to a clean and corrosion free bare metal surface. You will also do the same with all of the trailer lights.

Then check the actual wires. Any nicks in the wiring or frayed wires that result in copper strands touching bare metal on the trailer frame are going to cause a short. You can find and fix them as easily as wrapping up the affected area in electrical tape or go as far as replacing all the wiring.

expert reply by: Michael H

Davin G.

2/18/2024

So I have a similar issue. Whenever I plug the adapter into my truck the LEDs will indicate according (TM will light up with running lights on, LT will flash when left turn signal is on and RT will flash when right turn signal is on). However when I plug my trailer up, all the LEDs stay illuminated. (TM, LT, and RT) Any help would be much appreciated!

Jenny N.

2/20/2024

@DavinG Can you tell me how bright the trailer lights are? Are they dimly light? What we have found with LED lights is that the residual power from the truck connector is enough to activate the lights on the trailer. The draw is minimal enough that it will not drain the truck battery however we still recommend disconnecting the trailer from the truck when not in use.