Originally Posted by
studabear
Drivers door open takes some BMW out of drive. Brake light switch could be another Avenue of investigation?
and the bonnet. DSG gearboxes and most modern BMW auto boxes will select drive or reverse and instantly drop back to park if the bonnet is not latched properly.
if the engine is running, car is over 12v, voltage not an issue. I think the mechanic did not realise, assumes battery and charges it, then disconnects charger, closed bonnet to move into workshop and assumes battery was the problem