Locking the vehicle (mechanical key)
If the vehicle can no longer be locked with the SmartKey, use the mechanical key.
- Open the driver's door.
- Close the front-passenger door, the rear doors and the tailgate.
- Press the locking button ().
- Check whether the locking knobs on the front-passenger door and the rear doors are still visible. Press down the locking knobs by hand, if necessary.
- Close the driver's door.
- Take the mechanical key out of the SmartKey ().
- Insert the mechanical key into the lock of the driver's door as far as it will go.

- Turn the mechanical key clockwise as far as it will go to position 1.
- Turn the mechanical key back and remove it.
- Make sure that the doors and the tailgate are locked.
- Insert the mechanical key into the SmartKey.
If you lock the vehicle as described above, the fuel filler flap is not locked.
The antitheft alarm system is not armed.
See also:
Important safety notes
The use of seat belts and infant and child
restraint systems is required by law in all 50
states, the District of Columbia, the U.S.
territories and all Canadian provinces.
Even where this is no ...
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 ...
PRE-SAFE® Brake
PRE-SAFE® Brake is only available in vehicles
with DISTRONIC PLUS.
Observe the "Important safety
notes"
section.
PRE-SAFE® Brake can help you to minimize
the risk of a frontal col ...
