My 2017 MKC Reserve has autofolding mirrors and interior lighting options. My battery went dead and got jumped this week, since then welcome lighting has not worked. I have turned it on and off in settings, no luck.
If the battery is no longer holding enough charge and on the way of being bad, it would not turn on the welcome lighting to conserve battery life. Did you get a new battery? If not, I would test and replace and see that fixes it. You would also see a message about system shutting down to conserve battery on your center console when you exit the car too.