See also:

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. ...

General notes
If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged. •► Check the bat ...

Tow-starting (emergency starting)
Vehicles with automatic transmission must not be started by tow-starting. This could otherwise damage the transmission. ...