If you want some additional info on this:
1) I ordered this connector in Jan. 2023 for the '22 C 400 GT that I owned at the time:
This adapter cable fits exactly to the existing original connector of the S 1000 R/RR and XR and divides into three wires: - not needed This means that additional devices can be connected without any problems without cutting apart the expensive original cable tree. The right connector is located...
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2) In Oct. 2023, I ordered a less expensive version of the same thing, for the '23 C 400 GT that I now own:
Find many great new & used options and get the best deals for For BMW Motorrad Motorcycle Repair Connector 3 Pole 611656 8330 0413585 at the best online prices at eBay! Free shipping for many products!
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3) If you look at my personal C 400 GT gallery, in this particular image and caption, I identify the locations of the ground and hot (and unused) wires in that connector for you:
4) Starting with this particular image, I also have some nice clear shots of where you'll find that unused connector (which is intended for a BMW GPS):
5) Note that that connector is hot for exactly 60 seconds after the bike is turned off, so don't be freaked out, don't think you did any wiring wrong, when whatever you connect using that power source stays on for one minute after the bike is shut down.