The windshield wipers are inoperative

The windshield wiper drive is malfunctioning.

the Select another wiper speed on the combination switch.
at a Have the windshield wipers checked at a qualified specialist workshop.

    See also:

    Fuse box on the left in the direction of travel
    Open the hood. Remove any existing moisture from the fuse box using a dry cloth. AMG vehicles: remove the control unit above the fuse box. To open: undo screws 1 with an Allen key. ...

    Numerous stowage facilities, high degree of variability and temperature-controlled cup holder
    Numerous, easily accessible stowage facilities in the M-Class can accommodate bottles, mugs, keys, coins and much more. Each of the four doors can also easily accommodate a large 1-litre bottle. ...

    Brake fluid
    WARNING Over a period of time, the brake fluid absorbs moisture from the air; this lowers its boiling point. If the boiling point of the brake fluid is too low, vapor pockets may form in the ...