Shut off the vehicle and disconnect the negative wire clamp from the battery terminal post with an adjustable wrench. Unplug the six-pin plug between the vehicle and the trailer.
Strip all the colored wires at both ends with wire cutters. Leave 1/2 inch of bare wire exposed for connecting to the terminals on the six-pin connectors and the various vehicle and trailer locations.
Loosen the screw terminal for one of the wires connected to the plug on the vehicle or trailer side with a slotted screwdriver. The brown wires run to the tail lights, the green wires run to the right-hand turn signals and brake lights and the yellow wires run to the left-hand turn signals and brake lights. The white wires run to the trailer and vehicle grounds, the black wires run to the battery and trailer auxiliary power and the blue wires run to the electric brake controls.
Loosen the wire from its trailer or vehicle connection. Tape one end of the new wire to the loose wire end at the vehicle or trailer location end. Use the same color wire. Pull the old wire from the plug end until the taped end of the new wire arrives at the plug. Remove the tape and connect the new wire to the screw terminal on the trailer connector plug.
Connect the other end of the wire to the appropriate location on the vehicle or trailer. Make all new wire connections from the trailer or vehicle through the six-pin connectors as such.
