Was the car out in the rain?
Did P0015 show up with this issue? or has it been there for a while?
Why am I thinking BMW had an issue with some cars, quite a while back, with parking pawl issues, errors. Maybe a recall? Jsut a dead recollection, probably crossing my wires.....edit. Found some E53 stuff...
Also, do you have a BMW code reader? Might be a ton of errors your generic OBD is missing....