i have a four pole system with my jeep grand cherokee 2005. tail lights come on,but, brake and turn signals do not work??? what is the proper way to ground the ground wire on the trailer?? thanks for the help. also, the lights on the trailer have worked fine in the past.
Expert Reply:
I would recommend you use a circuit tester, like part # 40376, and test the pins on the 4 pole while each function is activated. This will narrow down the problem to the vehicle or the trailer. If it works properly, then the problem is on the trailer and vice versa.
Closely examine the pins and sockets on each side of the vehicle/ trailer connection, look for any corrosion, which will show up as a green discoloration. Many times, this corrosion will be enough to prevent a proper connection. Usually the ground wire coming from the connector on the trailer side attaches directly to the trailer frame on or near the tongue of the trailer. All the light fixtures then are grounded by being directly attached to the frame. If you find that you are getting the correct signals at the vehicle connector, then the problem exists on the trailer itself. You will have to trace the wires back from the connector, looking for broken or frayed wires.
expert reply by: Mike
