Just wondering- if I disconnect my battery, will I lose all the radio settings and custom settings that I programmed or are they retained in the key fob?
I am planning on lowering my windows a bit and keeping the boot open since I will be working back there and dont want it locked shut.

 

Disconnecting the battery will result in lost AM/FM settings. Although my satellite radio stations did stay programmed. I am uncertain about custom settings.

 

from having done it twice now (JCW steering wheel install and Mini Boost speaker and amp upgrade), each time all that was lost was the clock display. All the other stuff--which (other than the clock) does seem to be in the key, stayed as it was. And, no, I could not get the (closed) back hatch open while the battery was out.

 

You can buy a 9V battery to lighter plug / adapter at the auto parts that is designed specifically to preserve settings when the car battery is disconnected for about $5. I am not sure on the MINI what this will or will not save, but that is what it is made for.