Recommended 4-Way to 7-Way Wiring Adapter for 2003 BMW X5

Question:

I have a 2003 BMW X5 with the Draw-Tite hitch rated at 6000lb and 600lbs tongue weight and has the draw tite wiring harness that i believe is the same part as the 119250KIT. What would I need to do to convert it from the 4 PIN flat to the 7 Pole RV style? I tow a 2007 Ranger Bass boat that has a 5 way flat on the trailer. I have a 7 pole adapter that converts to 5 flat on my 2007 Chevy Truck and wanted the same setup on the X5. Thanks for all your help. P.S. I did also look into the 4 flat to 5 flat adapter where I would need to tap into the rear brake light to have my trailer release the brakes but i think the 7 Pole conversion would be a much cleaner setup and i could have more options.

asked by: Andy

Expert Reply:

I would recommend using 4-Way to 7-Way adapter # 37185, as this will not only convert your plug to the 7-way RV style, but it will also allow you to tow a 4-way trailer, if needed, without having to disconnect the adapter.

The # 37185 adapter kit includes a mounting bracket for a clean looking installation.

You would simply plug the adapter into your 4-Way plug, and then connect the additional wires as follows.

White: Ground wire, connected to a suitable grounding point on the frame.
Black: 12v Power lead wire, connected to the vehicle positive battery terminal with a 40amp circuit breaker, part # 9510 if needed.
Blue: Electric brake wire, connected to the electric brake wire from the brake controller in the vehicle cab, if applicable.
Purple: Auxiliary wire, connected to your vehicle reverse light wire behind the tail light assembly.

I have included a link to a video of the # 37185 adapter being installed, as a reference.