Question about 2002 BMW 3 Series

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Battery drains when not running

I have a 2002 325i with 100k and it has a battery drain problem and it won't start sometimes (at least 3 times a week.) We have to jump it off. This started happening about 6 months ago and I got a new battery only to find that the other one wasn't bad. Took the alternator off and had it tested (it was pretty much brand new) alternator was fine. Sent it to an electric motor shop, they went through it and found nothing, said it was a new alternator. I came to the conclusion that the owner before had the same problem. I discovered something today, I knew something had to be running for the batt to drain like that so I put my ear up against the dash and heard a motor noise (no key in the ignition). I decided to pull the blower motor fuse, that was it , it went off. Now that I've found the drain what can I do to fix it ? has anyone had this problem?


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I had the same problem. The blower motor resistor went bad. It's being replaced today

Posted on May 04, 2010


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I had the same problem on one of my cars it was the fan control module. replace that and it will fix the problem.

Posted on Apr 23, 2010


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