When I first got the 1982 300D, I couldn't figure out how to change the headlights from bright to dim. On American cars, its a repeating pull to toggle back and forth.
So I tried the turn signal stalk in all directions. But I did this while the sunroof was open. Pushed in, got the windshield washer - overspray got occupants through the sunroof. Live and learn.
Ken300D