I believe this is a feature on mine and all Sciroccos but i haven't needed them in so long i can't remember
Recently after a foggy night i got in my car and noticed my mirrors were fogged up - thought nothing of it as from memory they clear really quickly. Sadly they didn't clear at all and i can't remeber if i should be pressing something or if there is an issue i need to deal with but just wanted to check this is a feature before going mad.
You need to turn the mirror knob onto the heating setting to switch on the mirror heaters which will quickly demist them. Don't worry if you.forget to switch off as they.are on a 10 min timer.
Thanks mate