Running Lights on 1997 Dodge Ram Illuminate When Brake Controller and Fuse is Installed

Question:

I installed the tekonsha on my 1997 dodge pickup truck by splicing it into the plug for the factory trailer brakes. when i install the 40 amp fuse the running lights come on and stay on. this is before i connect to the trailer. Do i have my wires crossed?

asked by: Stephen W

Expert Reply:

It sounds like you have something feeding back into your running light circuit.

On that generation of Dodge Ram, the fuse you installed protects the power feed to the brake controller as well as the feed to the 12-volt power supply to the 7-way trailer connector. It sounds like you have a short in your trailer connector that is allowing power from the 12-volt circuit to bleed over to the running light circuit. The 12-volt circuit is wired to the terminal right next to the running light circuit, so if there is corrosion built up on the terminal or a loose wire, it could cause the problem you are experiencing.

I have linked you to our Trailer Wiring FAQ article that you might find helpful.

expert reply by: Mike L