My 2000 540i won't start. I have parasitic drain. The battery keeps getting drained by something that has gone awry in the electrical system. I have replaced the alternator, pulled the GPS/computer system out and it still won't start. My mechanic is so kind to me and has spent a lot of time trying to figure this out by unplugging everything in the car one by one and letting it sit to see where the drain is coming from. The battery is new. Actually, I have had three new batteries in the last five months (all covered by CAA/AAA). I am so frustrated and am thinking I am done with my car. However, it is in immaculate condition and drives so beautifully that it would be a shame to put it to landfill. Anyone have any ideas what it could be? I am at my wit's end at this point!