See also:

Replacing the rear window wiper blade
Removing the wiper blade WARNING The wiper arm could be set in motion and injure you if the wiper is switched on. Remove the key from the ignition lock before replacing the wiper blade. - R ...

Mercedes-Benz M-Class Owners Manual
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Important safety notes
DSR assists you when driving downhill. It keeps the speed of travel at the speed set on the on-board computer. The steeper the downhill gradient, the greater the DSR braking effect on the vehi ...