Recommended Wiring, Brake Controller and Trailer Hitch for 2015 BMW X3

Question:

Im purchasing a hitch and wiring harness for my 2015 BMW X3. Need advice on the wiring. Your recommended 119250KIT provides a 4 flat for the lighting connections. But what if I need an electric brake controller? Is there no recommended wiring harness that includes a 7 pin connector so the brake controller can be part of the package? Is my only choice to separately buy the installation kit for trailer brake controller, ETBC7 that plugs into the 4 flat. Seems like a trailer wiring harness ought to include the option of a 7 pin so I can easily add a brake controller?

asked by: Roger R

Helpful Expert Reply:

For your 2015 BMW X3, the Tekonsha ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT is a confirmed fit. As you mentioned, this will be installed in order to provide a 4-way connector in order to send power to the trailer lights. If you need to add a brake controller to control your trailer's electric brakes, you will need to also install the Universal Kit # ETBC7. This kit includes everything needed to install a brake controller and 7-way connector.

There is not a single wiring kit available that will allow you to install all the necessary wires for trailer lighting and electric brakes. I have attached an very helpful article that details installing a brake controller from scratch.

For a brake controller I recommend the Tekonsha Prodigy P2 # 90885. This is a great proportional brake controller that will activate your trailer's brakes at the same time and with the same intensity that you apply to them in your BMW. It includes a digital display and continuous diagnostic checks to alert you to any potential issues. This controller is known for its reliability and ease of installation. I have included a video demonstration and the installation details for your review.

For a trailer hitch, I recommend the Curt Class III Receiver Hitch # C13316. This is a 2 inch trailer hitch receiver with a tongue weight capacity of 350 pounds and towing weight capacity of 3,500 pounds. I have attached the installation details for you to check out.

Lastly, for towing you will need a ball mount. I recommend the etrailer.com Ball Mount Kit # EBMK4 that includes a 2-3/4 inch Rise or 4 inch Drop Ball Mount as well as 2 of the most common sized hitch balls. I have attached a link to our available selection of ball mounts as well as an article that details how to choose the correct one for your setup.