It is strange that it worked fine for days. I assume you had an airbag fault light on. Not ideal if you are going to get in a deadly accident.....
My car had the same sort of failure after a two seperate DCFC sessions.
I posted about my horrible experience getting Chevy to fix it, even though it was still covered by the 8yr / 100k mi. power train warranty.
You should read through my sad story here: viewtopic.php?f=2&t=5165
It's a long 7 page thread. Sorry. But you should read through it.
My bet is the same module that finally fixed my car
, that was tried on the 3rd attempt, is the module that your car will need.
To bad you couldn't get the front seat back to normal position and plug the airbag connectors back together BEFORE the Chevy dealer touched it...
It would have then have been a normal Power Train repair,,, maybe with an airbag fault that would have cleared easily.
Please keep us posted and tell us how bad your dealership troubleshooting experience is... Don't let them sell you the $800 SDM.....And have them do a DCFC before you take the car back. Witness it if you have to.
Used '14 2LT w/ DCFC. +69 K miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 2nd guess not covered by warranty and cost $800. 3rd guess fixed the problem.