A nice one I stumbled upon in Elsa:
I guess everybody knows that with xenons, you just enable "the thing" via MMI. However, the auto dimming mirror has a life of its own! It needs to be separately adjusted (I guess that is why mine wasn't working as good as I was expecting it to this summer)!
So, according to the write-up, the magic happens like this ("button 2" being the on/off button on the mirror according to the diagram):

/quote/

– Press and hold button -2- for 12 to 15 seconds until display shows “L” (for left-hand drive vehicles) or “A” (for right-hand drive vehicles).


– Press the button again briefly to change the setting for right-hand or left-hand drive.

/quote/

Can anybody confirm this works on their vehicles (as, in my case, there is nothing on the display)?