All seems to be OK for now. Here's what I did:
- Deactivated the High Voltage.
- Removed the new battery and put it on the trickle charger overnight.
- Reinstalled the new battery.
- Reactivated the High Voltage.
- Jumped into the cockpit, plugged in the ODB.
- Turned on Accessories...
Woke up yesterday and the 12V accessories battery was dead dead.
Nothing worked.
So I disabled the High Voltage system and removed the old 12V battery.
Measured below 10V.
Figured it's an old battery and needed replacing, so took a trip to my local BMW dealer and picked up a new OEM replacement...
