I've been living with this tiny irritating problem for awhile. The first time I replaced the battery in my M3, the auto-up on the drivers window quit working, then after a couple days it magically started working again. All was fine for a few years, but earlier this year the battery started not wanting to go on cold mornings, so I put in a new one. Now on battery #3, not bad. And no surprise, the drivers auto-up quit working again. But this time it hasn't come back. Doesn't seem important enough to justify a dealer visit, but it was a nice feature when it worked. Anyone have a clue?