I have a 4 month old MS 90D. Thursday night I went to drive home from a school function, half block out of the school parking lot went to stop at stoplight, heard a "clunk" from the front, immediately had an alert that car unable to drive. Pulled up alerts on main screen and had both a front drive unit disable, reduced performance and a car unable to drive alerts. Like
@f-stop, PRND indicator all red and car would not respond. Called Roadside Assist from inside the car, they sent wrecker to pick it up, and delivered to service center Friday am.
Had call from service on Friday, asked me to explain what happened, they said car was now operational, but they had opened and investigation case with Engineering. Advised likely Monday before I would hear back.
Heard from them today, and diagnosis is that issue is a firmware error. Here is the exact text from my service repair invoice: "... Engineering found a rare bug in vehicle. States this should not duplicate again". Vehicle is being returned to me in the morning (about 70 miles from service location).
I asked if they had loaded a firmware update from engineering to fix the bug. They had not as I already had what is latest firmware available, Ver 8.0 (2.36.108). What I was told by service advisor is that if you get out of the vehicle, lock it, and then unlock, the diagnostic will reset and car will be operational.
I have no idea if this is possibly something new in Ver8.0 related to enhanced regen braking (although I was at relative low speed when had the original fault), but if you happen to have this and get a disabled vehicle, you might want to get out, walk away so vehicle locks/powers down, and unlock to see if it clears so you an at least drive until you contact service.