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. ...

Warning and indicator lamps
  ...

Checking tire pressure electronically
  Make sure that the SmartKey is in position 2 in the ignition lock.   Press the or button on the steering wheel to select the Service menu.   Press the or button to sel ...