See also:

Mercedes-Benz M-Class Owners Manual
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Setting the temperature
2-zone automatic climate control Different temperatures can be set for the driver's and front-passenger sides. ► Turn the SmartKey to position 2 in the ignition lock. ► To increase/ ...

Setting the center air vents
1 Center air vent, left 2 Center air vent, right 3 Center vent thumbwheel, right 4 Center vent thumbwheel, left - To open/close: turn thumbwheels 3 and 4 to the right or left. ...