I've got this Euro OEM BMW F07 trailer wiring harness/interface kit that, if the factory vehicle wiring harness is prepped for it, will literally just plug in and perform the trailer functionality (well, you have to program the car to recognize it afterwards). BUT, USA delivered vehicles, do NOT put that prep in any vehicle that does not have a USA approved trailer option from the factory...mine, does not while it is available most anywhere else in the world.
So, I've got this interface box designed to plug into the vehicle into an existing plug - no pinout documentation (since it's supposed to be just plug-and-play), and without it and a mating plug to wire up my own, currently useless to me! The actual trailer connector harness also plugs into factory sockets, but those functions come from the module, and if I can find out the pinout, I can handle that connection by cutting off the existing plugs and wiring it into a new one.
I'd like to know if anyone has the wiring diagrams that show this connection. If so, I should be able to cobble up how to interface it into my car.
My alternative is to try the Right Connections kit, but they will not guarantee it will work on a USA model (likely it would, but I don't want to buy one, install it, and find out it won't!). The Westfalia harness probably would also work, and may use the same Hekbako interface module, but I haven't looked into that one much, yet.