See also:

Mercedes-Benz M-Class Owners Manual
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Switching the rear-compartment climate control on/off using the rear control panel
Turn the SmartKey to position 2 in the ignition lock. To switch on: press rocker switch 15 up or down and select AUTO. or Press rocker switch 15 up or down and select MAN. To switch of ...

GVWR (Gross Vehicle Weight Rating)
The GVWR is the maximum permissible gross weight of a fully loaded vehicle (the weight of the vehicle including all accessories, occupants, fuel, luggage and the drawbar noseweight, if applica ...