Why is my alarm going off for no reason?
http://www.bimmerfest.com/forums/showthread.php?t=100056 --- take a look at this. Seems a lot of other owners having the same problem. Seems with most of them it was the hood switch. Hope this helps. Drive safe.
That was my problem also. I unplugged the plug that is attached to the driver side cabin air filter, haven't had the problem since.
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