2010 l322 seemed to be running well. No major codes. All of a sudden I get the gearbox fault on the dash. Hook up the scanner and lots of codes for BCM ECU TCM and others saying no vin or no communication. Shut off car and restart and all seems ok. Don't suspect transmission as the system is loosing communication with every module when the warning comes up.

Any suggestions where to start?

I've started with the battery and it had just come off the charger before this happened. 12.7 volts with motor off and ignition on.

US spec 5.0 petrol if that matters