[TwistedMunky87]

2011 258I. Bought the vehicle 2 years ago from a dealer. The next day I had to take it to a BMW dealer due to a Faulty power distribution box and junction box for electronics. Over the last two years it has been great. I bought the vehicle to drive for a couple of years and give to my son as his first car. Well went to teach him how to drive and got several faults and the car shut off. Here are the symptoms.

Ran parked for 15 min in the driveway no problem. Left the house and a block away it shows these faults and dies.
Transmission failure
wiper failure
driver restraint failed
passenger restraint failed.

I wait 20 min and it starts up and drives home. I leave it running in the driveway and return to it later and find it has failed again. Wait a day and go try and run codes using two different code readers. Both show no faults. Drive again and it repeats the process again but when it dies, I lose communication on the ODB port. Just attempted with ISTA and no communication, No wipers, No windows or seat controls.

[M_Bimmer]

Post your battery voltage (across the battery terminal), with car off, and another value with accessory on....

Unlike old alternator-battery systems, the alternator doesn't always charge the battery...

You could have a bad battery, or a bad alternator, or both now.....

With voltage values, we can rules them out....or not...