See also:

Coolant temperature display
WARNING Driving when your engine is overheated can cause some fluids which may have leaked into the engine compartment to catch fire. You could be seriously burned. Steam from an overheated e ...

Mercedes-Benz M-Class Owners Manual
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Setting the side air vents
•► To open/close: turn thumbwheel 3 up or down. Side window defroster vent 1 is never completely shut, even if side air vent 2 is shut. ...