See also:

Please bear the following in mind
At the onset of winter, have your vehicle winterproofed at a qualified specialist workshop, e.g. at an authorized Mercedes- Benz Center. Observe the notes in the "Changing a wheel" sectio ...

Important safety notes
Do not leave the SmartKey in the trunk/cargo compartment. You could otherwise lock yourself out. WARNING When leaving the vehicle, always remove the SmartKey from the ignition lock. Always ...

Problems with the SmartKey
Problem Possible causes/consequences and Solutions You cannot lock or unlock the vehicle using the SmartKey. The SmartKey battery is discharged or nearly discharged. ...