Mercedes-Benz C-Sedan 2014 Owners Manual - Manual (Page 85)

Automatic locking feature
The vehicle is locked automatically when the
ignition is switched on and the vehicle's
wheels are turning at a speed in excess of
9 mph (15 km/h).
You could therefore be locked out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is on a roller dynamometer.
X To deactivate: press and hold button :
for about five seconds until a tone sounds.
X
To activate: press and hold button ; for
about five seconds until a tone sounds.
i If you press one of the two buttons and
do not hear a tone, the relevant setting has
already been selected.
You can also switch the automatic locking
function on and off using the on-board
computer (
Y
page 217).
Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm
system will be triggered (
Y
page 73).
X Take the mechanical key out of the
SmartKey (
Y
page 78).
X Insert the mechanical key into the lock of
the driver's door as far as it will go.
X Turn the mechanical key counter-clockwise
to position 1.
The door is unlocked.
X
Turn the mechanical key back and remove
it.
X Insert the mechanical key into the
SmartKey.
Locking the vehicle (mechanical key)
If the vehicle can no longer be locked with the
SmartKey, use the mechanical key.
X
Open the driver's door.
X
Close the front-passenger door, the rear
doors and the trunk lid.
X Press the locking button (
Y
page 82).
X Check whether the locking knobs on the
front-passenger door and the rear doors
are still visible. Press down the locking
knobs manually, if necessary (
Y
page 82).
X Close the driver's door.
X Take the mechanical key out of the
SmartKey (
Y
page 78).
X Insert the mechanical key into the lock of
the driver's door as far as it will go.
Doors
83
Opening
and
closing
Z