my Cooper had this happen about six months ago. ran the battery down as I was unaware it was sitting with the fan running. Ended up being a bad relay that was a part of the fan. They had to replay the fan entirely, as the relay was integrated into the fan. Just be mindful of when they do disconnect things to replace it, the radio may come up 'DISABLED'. Mine did and without the four digit code to enter into the radio I can not get the radio to play now. Dealership has that code but wouldn't release it without doing a diagnostic on the car. I know that they have the code as long as I have the proof of ownership.