I just had to replace my footwell module. My understanding is this happens when you disconnect the battery for a repair and the module is still doing some eprom magic, and crashes when the power is abruptly removed. It has been suggested that leaving the car locked for 20 minutes allows the module time to finish its business. I don't usually have the time to wait 20' to start the repair so am looking for more expedient options to safely disconnect the battery.

Has anyone tried using a when disconnecting the battery? This would allow you to leave the ecu powered while disconnecting the battery, and should in theory eliminate this problem.

 

I replaced my battery in my 08 this last December and had the battery removed from the car for about a month. I never had any issues with anything. I would reccomend removing the negative terminal first, then the positive. When installing, positive first, then negative.

 

Thanks. I always remove the battery terminals in the order you suggested. This is a known issue with Mini and BMW footwell modules from this era. The eprom needs to finish writing after an undetermined amount of time after shutting off the car, and if you disconnect the battery before the eprom is done it corrupts the eprom. I have disconnected the battery on multiple occasions before and had not had this problem, but this time it bit me. The solution seems to be to shut off and lock the car for an hour, then disconnect the battery.