No Running Lights on Boat Trailer and Camper Towed by a 2012 Dodge Ram 2500

Question:

need help troubleshooting why I dont have any tail-lights and side marking lights for my boat trailer which is a 5 pin and on my Outback camper which is a 7 pin.

asked by: Michael

Expert Reply:

The first thing you are going to want to do is use a circuit tester like # PTW2979 if needed and test the connector on your truck to make sure all of the functions are working. If they are not use the owners manual and/or the legend on the power distribution box lid to find the locations of any fuses or relays related to the tow package wiring and replace any that are faulty.

If everything checks out on the truck side then that would indicate problems on the trailers. Most likely there is a bad ground or grounds and there could also be corrosion build up in the connectors. The main trailer connector grounds and the grounds for each of the lights need to be attached to clean and corrosion free bare metal surfaces. On the 7-Way connector, check to make sure there is no corrosion built up where the wires attach.

If either trailer frame is aluminum or has a tilt bed or tongue then you will need to run jumper grounds from the lights to the main trailer connector ground.

It does sound like an issue with the vehicle side running light circuit and possibly a blown fuse or bad relay.

If you are using a 7-Way to 5-Way adapter you can also check to make sure the adapter is working properly by plugging it into the vehicle and using a circuit tester to test the 5-Way pins.

expert reply by: Michael H