2011 GL550, has anyone had the code P0620 or knows how to fix, "Operational fault of component G2 (Generator)"? I scanned the car today with my Autel scanner after the red battery logo came up while driving off the driveway.

 

I would say a bad alternator (generator) is a good guess. Start by checking the connections on it. It's also possible for the belt to slip if the tensioner is bad, but you would also notice increased steering effort if the belt is slipping.