Recommended 4 Flat Trailer Wiring Harness for a 2021 BMW X3 M40i

Question:

regarding part#TK77FR. I have a 2021 BMW X3M40i. What is the difference between the M and Exclude M wiring harness? The M40i is not a full M badge but it has mostly M features. Im not sure which one to get. Also do I understand that this will not require programming? thanks

asked by: Dave

Expert Reply:

You are correct in that your 2021 BMW X3 M40i isn't actually from the actual M division, so it does make the correct wiring look difficult to locate. However, the 2021 model year makes life significantly easier as the Tekonsha T-One # TK77FR will fit both the M and non-M models, so this is definitely the harness I recommend for you. Other than a wire that will need to be run up to the battery for needed power, it will be a plug and play option. It is always a good idea to reset the vehicle's electrical system by disconnecting the battery and then reattaching it before the initial use, but you will not need to any other kind of programming to get it working.

expert reply by: Lazer S