Wanted to add a little info to the thread. I was having the same issue on my 2002 Cooper S. I changed the bulb...nothing. I found this thread so I went to my Mini dealership and had them order the switch. Replaced the switch yesterday afternoon...nothing. After some troubleshooting with my multimeter I discovered that all the connectors and switches were working fine. The problem ended up being the contact on the side of the connector where the bulb goes. It was pushed back and wasn't actually making contact with the bulb. Pulled it out some and it worked like a charm. Oh well...you live and you learn.

 

Updated: I was able to find the cable by removing several items above the reverse switch. In case it helps anyone in the future, the cable originates from under the fusebox in the engine compartment. Keep in mind that this refers to a 2009 r56. The connector was simply overlooked when my mechanic replaced the engine the last time. Reverse lights now work as they should.

Original post:

I've been searching for some pictures or info on a weird problem that I'm having with my back up switch on my r56 (yes I know what forum this is but it appears that someone in this thread might be able to help my particular problem!)
I found the back up switch and there is no cable attached. I've searched what I can see and I don't see the plug or wires. Does anyone know where the wires and cable connecter originates? It might help me know where to focus my search. Thanks if you can help!

 

Very nice write up and display of pictures/steps. I know this is a very old post, but hoping someone can help me. I have the new switch and found the hole for it (thanks to your pics), but the sensor is gone and I can’t find the wiring for it to connect the new one. I don’t know if it was loose and fell out or what, but it’s gone. I have looked all over for the wire/connector, but am clueless as to where it is. Any idea where the wire runs from to go to the switch in the transmission?

Thank you in advance!