See also:

Automatic engine switch-off
The ECO start/stop function switches the engine off automatically if the vehicle is braked to a standstill and the brake remains depressed with the transmission in position D or N. You can st ...

Mercedes-Benz M-Class Owners Manual
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Collision warning
If a vehicle is detected in the monitoring range of Blind Spot Assist and you switch on the turn signal, a double warning tone sounds. Red warning lamp 1 flashes. If the turn signal remains on, de ...