See also:

Slippery road surfaces
WARNING The outside temperature indicator is not designed to serve as an ice-warning device and is therefore unsuitable for that purpose. Indicated temperatures just above the freezing point ...

Mercedes-Benz M-Class Owners Manual
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Cleaning the wiper blades
WARNING Before cleaning the windshield or wiper blades, switch off the windshield wipers and remove the SmartKey from the ignition lock. On vehicles with KEYLESS-GO, press the Start/Stop b ...