See also:

How the occupant classification system works
The Occupant Classification System (OCS) categorizes the occupant on the frontpassenger seat by means of a weight sensor. The front-passenger front air bag is deactivated automatically for cert ...

Snow chains
For safety reasons, Mercedes-Benz recommends that you only use snow chains which have been specially approved for your vehicle by Mercedes-Benz, or are of a corresponding standard of quality. ...

The windshield wipers are obstructed
Leaves or snow, for example, may be obstructing the windshield wiper movement. The wiper motor has been deactivated. For safety reasons, you should remove the SmartKey from the ignition lock. ...