If you are into hacking up your factory harness!

A good many owners and professional installers (not hacks like you find at auto stereo shops, hitch shops) will NOT use the 'crimp on' wire taps...


And finally, a cautionary tale:

X5 Trailer Receiver/Wiring/Brake Controller Install (What not to do!) - Bimmerfest - BMW Forums

when I first got my new X5D in 2012, I need a hitch install. checked all my local stealership, none of them really wants to do it. gave me the turn around, so I checked a place called Rack N Road. they do hitches and rack for all cars/tracks. when I dropped by the shop, they got an 2010 X5 really to install a hitch. The owner was cool and I asked for his number to check how his new hitch install. After a few weeks, I called him. he told me no issue and he uses it daily on a trailer. so I went back to Rack N road and got mine install.
Here are mine findings:
the aftermarket hitch is a replacement of the stock rear reinforcement bumper
Hitch sits lower than stock
no bumper cutting (when I did this, my X5D was new. did not want to cut my new ride)
they hacked the wires in (Not sure how, but it works fine) the only bad thing I can think of its when I need to reverse with a trailer. The parking sensor go off. since I do not use my hitch very often, I just live with it.

You don't want to cut your new ride but you let them hack the wires?

The OEM trailer wiring harness isn't that much in the grand scheme of things.

yes, I let them hack the wires, since I had a X5 who done it two weeks before me, and he had no issue. I had no issue since it was hacked back in 2012 either.

Radar sensor will go off anytime something is behind the car, a bike rack etc.

Tapping into the wires is not "hacking".

You are adding a sensor wire to detect when the light is energized, then the powered relay module sends 12vdc to the trailer lights.

Seriously, it's not a big deal.

(I'm a computer and electronic technical service manager. I work on million dollar systems every day WAYYY more complicated than trailer wires.)

BTW I installed my own hitch too.