Running Lights Not Working On Trailer Towed By 1993 Jeep Cherokee

Question:

Trailer side lights work when on my car but does not work when towed by my 1993 cherokee jeep trailer blinkers brake lights all work but side lights

asked by: Bob

Expert Reply:

It sounds like there is an issue with the 4-way connector on the 1993 Jeep Cherokee since the lights work on the trailer when you tow with another vehicle. The first step is to check that the ground on the 4-way connector on the Jeep has a nice solid ground connection to a clean bare metal surface of the vehicle's frame. You also want to make sure that the pins are free of any corrosion. If you see rust on the pins you can lightly sand it off with a fine grit sand paper. Sometimes if the 4-way connector does not get a good connection with the trailer side connector because of rust or bent pins.

If your connections are good, I recommend to make sure you are getting power from the running light pin on the 4-way connector with a circuit tester like part # PTW2992. I have attached a very helpful that shows how to test the 4-way with a circuit tester. If you do not have power on the tail light circuit then you either have a blown fuse in the Jeep or the wiring harness needs to be replaced.

expert reply by: Heather A