Parts Needed to Install a Trailer Brake Controller on a 2005 Ford Explorer with Factory 4-Way

Question:

I would like to install the Tekonsha Prodigy brake controller. I have a flat 4 plug trailer lights connector in the back and have found a 7 plug connector under glove compartment to plug the controller into with the ford harness...The connector under the glove compartment must go somewhere...Everyone is saying I need part #37185...Even though I do not have the Class 3 towing package, what does this plug do? It must be part of the harness that goes to the rear for the a 7 pin trailer light/brake connector that would be part of an upgrade package...I wonder where the other end of that harness is in the back...Is there an option for utilizing this harness to go from flat 4 to 7 pin in the back. Part # 37185 is a full rewire...Why do that if the connector is there in the front for the controller and maybe has a plug somewhere in the back to hook up a 7 pin plug, much like the F150 setup...Thanks for your help in advance...

asked by: Greg R

Expert Reply:

You can use that factory port for the brake controller, however, there is no 7-Way kit available for the 2005 Ford Explorer with factory 4-Way. You will have to find were the blue wire for brakes terminates. From our experience it terminates in a harness behind the driver side wheel well or behind the door. You will need to route a length of wire # 10-1-1 from this point back to the # 37185 blue wire.

The black wire will need to be routed under the vehicle and to the positive battery terminal via a 40 amp circuit breaker # PK54540. You can use the same 10-1-1 wire. It will need to be long enough to reach from the 7-Way black wire to the battery. You will need to avoid areas that could pinch or burn the wire.

The white wire grounds to the frame, the purple wire attaches to the reverse light circuit behind one of the tail lights. If the trailer does not have reverse lights, you do not need to connect this wire and it can be taped up and stowed out of the way.

You could also use the 4 and 7 Way Installation Kit, # ETBC7, which comes with the 37185 adapter, circuit breakers, and wiring. I have incldued a link to an FAQ article that should help with the installation. You only need to focus on the parts regarding routing wire from the blue and black wires on the 37185.

expert reply by: Michael H