Hi
I have exactly the same problem with my 2015 640d
It started when I discovered that my phone connection had failed.
In the connection menu I noted that the bluetooth was turned off.#
I turned it on and started to connect my phone.
After 20-30 seconds the screen went blank and the screen rebooted.
It also wiped out all data from the satnav and the radio settings.
It then constantly worked for 20 seconds then rebooted again and again
I managed to get in and turn the bluetooth off
It is now staying on but my sat nav info has gone but able to tune in on radio but cannot save stations.
Dread to think how much BMW will charge to fix all.
Hope this might help.
If anyone has a fix please let me know
Thanks
Hilary
