Trailer Lights Not Functioning On a 2004 Jeep Grand Cherokee

Expert Reply:

It sounds to me as if you are trying to say that you have power at the trailer connector but not at the trailer lights. If this is the case you most likely have a ground issue. I would start by checking all of the ground connections on the trailer and making sure they have good solid clean connections. Check the wire at the trailer tongue and check the tail lights connection to ground. Usually the tail lights are connected through their mounting hardware so you will need to make sure that the ground connection is good and that there is nothing keeping the ground/mounting studs from making solid contact with the trailer frame. Sometimes there is a plastic license plate holder mounted behind the left side tail light that will cause this issue.

expert reply by: Bob G