Alarm going off randomly

[choll]

Posting here because I am desperate. 2016 x5 alarm has been randomly sounding without any prompting. First time happened after oil and fluids were changed. One cold morning the dashboard said "drivetrain malfunction, drive moderately" but the car was fine and drove normally. Since then the alarm has sounded while driving, overnight while the car was parked, and random hours.

BMW has not yet been able to diagnose the problem, they have asked me if I had work done to the bumper which I have (car was swiped while parked in the street and needed bodywork), but this issue started before then. They also wanted to know if i had anything plugged into the port in the glove box (no, but bought preowned so who knows what previous owner did) or if the car ever had water damage (no, minus noticing some water stains router login 192.168.l.l.link/ by the driver side sunroof one day).

They now want permission to remove the bumper at an additional cost of $750 to try to continue to diagnose the issue, stating that the alarm system is housed in the bumper. I asked if they checked the hood sensor and they said it was fine. Any direction anyone could point me in would be appreciated.

[Qsilver7]

Is anything plugged into your OBD II port in the footwell (not referring to the USB ports)? I don't know if Austria is LHD or RHD...so I'll refrain from saying the OBD II port is in the driver's foot well as that's were it's located on LHD (left hand drive) vehicles.

Also, how old is your main 12 volt battery? A battery with low voltage can cause lots of electronic glitches...and set off the alarm if the voltage drops low enough. The DWA (anti-theft alarm siren system) can interpret a drop in voltage as a theft attempt and set off the alarm.

OBD II port location:

[1norseman]

Check for water under the carpets, and rear side storage compartments.
Make sure you don't have plugged sunroof drains, leaking water into the car, that is messing with the electronics in the back...

[CatalinP]

The alarm unit enclosure is under the rear bumper right corner. It is prone to moisture and dirt accumulation.