Odd Battery Drain has even stumped the dealership
 

A few weeks ago I had my wagon's battery disconnected for a local car show. It sat this way over the weekend. After I hooked it back up, I got a high battery drain error message every morning. Did a battery test, checked all grounds, etc. I was stumped so I took it to local dealer for diagnosis. They were unable to determine the issue, but could definitely tell the car was waking up on its own. Any ideas? No meaningful codes that I could read. Car has been there all week now and they've even had to bring in an engineer from outside the dealership to help diagnose. Narrowed down to 3 possible modules causing the trouble, of twenty possible. I'm just going off of what my service advisor is telling me - and for now enjoying the tech in a 2019 x3.

At least it wasn't something simple that I could've figured out on my own? All car features appear to still work, no water damage either. This will be one expensive car rental, may as well make the most of it.

Here's a photo from the show.
Attachment 165151

Well, we've narrowed it down to the passenger side comfort access door handles. And some wiring corrosion. Time to diy and avoid that 2k bill .
wish I had Just tried removing the comfort access fuse and saved some money.