See also:

Opening
You can open the trunk lid using the SmartKey. Press and hold the button on the SmartKey until the trunk lid opens. ...

Vehicle remote opening
If you have unintentionally locked your vehicle (e.g. the SmartKey is still in the vehicle) and a replacement SmartKey is not available, the vehicle can be opened by a Mercedes-Benz Customer A ...

Changing the battery
You require a CR 2025 3 V cell battery. Take the mechanical key out of the SmartKey (). Press mechanical key 2 into the opening in the SmartKey in the direction of the arrow until batte ...