Reverse Lights on Dodge Ram 2500 Series Stay On When Trailer is Connected

Published 02/23/2011

Question:

Dodge 2500. Backup lights on truck stay on when trailer hooked up. Found black wire on trailer harness connected to center pen. Changed black wire to 11 oclock position. Will this help

asked by: Sam W

Expert Reply:

The circuit that provides power to the reverse lights should be wired to the center pin on the 7-way trailer connector on your vehicle. It sounds as if you will need to do some troubleshooting to determine the cause of your problem.

Check the plug on your trailer for corrosion or damage. If you find any green or white corrosion in any of the sockets on the connector, there is a good chance that the corrosion has spread to the interior of the connector, causing a short or feedback back into the vehicle wiring. You will also need to determine that the vehicle side connector as well as the one on the trailer is wired correctly. We have a great wiring FAQ article that I will link you to that will show you how everything should be wired.

Are you using an adapter? If so, you will also want to check the adapter to make sure that there is no corrosion as well.

Do you have a battery mounted on your trailer? If the connector on the trailer or adapter is wired incorrectly, power from the battery could be feeding back into the reverse light circuit on the vehicle. Have you put the truck in reverse yet with the trailer connected? If the reverse light fuse blows, you know for sure something is feeding back.

expert reply by: Mike L