Parasitic Battery Drain e53

[Bmwe5320023.0]

My advice is to first get the battery tested. Batteries that had a drain problem could be damaged, as was in my case. I thought my battery was new, less than 5000km on it. Well it was dead and didn't hold a charge.
Then just measure what's your amp draw once the vehicle goes to sleep.
Once you now the draw, you can start either pulling fuses or doing voltage drop test to identify where the drain is.