A few times in traffic, if I leave the “Start/Stop” feature active, it will try to start and fail. This is more common on an incline. It will then become impossible to restart - unresponsive to attempts. I’ve gone so far as to get out of the car, lock it, walk away, come back, unlock it, get back in, and retry, to no avail. Each time has blocked traffic, so it’s a bit of a safety issue as well.

In each occurrence if you simply wait long enough (5-10 minutes) it will “fix itself”. As a software engineer myself, I’ve got a hunch there’s a bug in the code that eventually gets timed out by a watchdog, and that’s when I’m able to restart. I’m just hoping the issue has been caught/fixed by MZB in a bulletin, as I don't expect my dealer to chase it (it's a once-every-50-drives thing).

Anyone else experience it or know anything about it?

Thanks!

 

First step, check 12V/12AH auxiliary battery in trunk (part # 0009829608).

 

I have never had that happen in my 2016 S550 coupe. My experience has been that the system won't stop the engine at a stop unless I have driven a long distance at high speeds. But when it does stop it always has restarted as soon as I pressed the throttle.