Took the utility trailer to the dump today....the parking lights on the side of the trailer work, but on the rear, only one out of 4 lights work. The parking/brake and directional is completely out on the drivers side, and on the pass side...parking is working, but brake and directional not working. I checked all the bulbs, and all are fine. I am thinking the wiring harness where it makes the connections is bad, as where you plug in the male/female part these is a lot of crud/bluish green stuff around the contacts....cleaned out as best as I could and just got the side lights to work. Best bet just replacing both the male/female wiring harness? (I don't have a ohm meter to tell if the current is making it to the rears) Thanks.