2006 bmw 650i battery drain

an alarm system going on and off would be the first place I would look and most likely causing your draw. The fuses are located behind the glove box. there is a panel in the back that you can open to reveal the fuses.

Awesome response, I will check behind the glove box and look for that fuse. Once I remove the fuse I will drive the car and see if that is my problem. Quick question, have you ever used a multimeter before? How does that work, and what part of the fuse box do I place the positive and negative probe. "I have never used this tool before." Do I take out the fuse and stick the probes in its place? I hope that this makes sense to you.

With the fuses exposed, Clip the negative cable of the multimeter to a good ground with no paint, usually a bolt head works, then with the positive cable, probe the two metal sections of the top of each fuse on either side. You should read 12V on each side, then the fuse is good, 12V on one side, the fuse is blown. You can also remove each fuse with the fuse puller that is usually on top of the fuse panel and inspect them visually.

You're working on your BMWs electrical system without the knowledge of where the fuse panels are located and without having ever used a multimeter before. I'm guessing that the work you did is what caused your current problems. You're on the right path to creating a massively high repair bill. Please stop what you're doing and have a mechanic/electrician do these repairs.

Get a good repair manual before you damage the electrical system.