
If you do not open the vehicle within
approximately 40 seconds of unlocking:
R
the vehicle is locked again.
R the theft deterrent locking system is
armed again.
X To lockc entrally:press the 000Dbutton.
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid
R the fuel filler flap
The tur nsignals flash onc ewhen unlocking
and three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (Y page 246).
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 245). KEYLESS-GO
General notes Bear in mind that the engine can be started
by any of the vehicle occupants if there is a
KEYLESS-GO key in the vehicle.
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry
the SmartKey with you. You can combine the
functions of KEYLESS-GO with those of a
conventional SmartKey. Unlock the vehicle
by using KEYLESS-GO, for instance, and lock
it using the 000Dbutton on the SmartKey.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the
corresponding door handle must not be
greater than 3 ft (1 m). Ac
heck which periodically establishes a radio
connection between the vehicle and the
SmartKey determines whether a valid
SmartKey is in the vehicle. This occurs, for
example:
R when the external door handles are
touched
R when starting the engine
R while the vehicle is in motion X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor
surface 0002.
X Convenience closing feature: touch
recessed sensor surface 0003for an
extended period.
Further information on the convenience
closing feature (Y page 97).
X To unlock the trunk lid: pull the handle on
the trunk lid.
The vehicle only unlocks the trunk lid. Changing the settings of the locking
system
You can change the settings of the locking
system. This means that only the driver's door
and the fuel filler flap are unlocked when the
vehicle is unlocked. This is useful if you
frequently travel on your own.
X To change the setting: press and hold
down the 000Eand000D buttons on the
SmartKey simultaneously for SmartKey
83Opening and closing Z 

approximately six seconds until the battery
check lamp flashes twice (Y
page 85).
i If the setting of the locking system is
changed within the signal range of the
vehicle, pressing the 000Dor000E button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock the driver's door: press the
000E button once.
X To unlock centrally: press the000E
butto ntwice.
X To lock centrally: press the000Dbutton.
The KEYLESS-GO function is changed as
follows:
X To unlock the driver's door: touch the
inner surface of the door handle on the
driver's door.
X To unlock centrally: touch the inner
surface of the front-passenger door handle.
X To lock centrally: touch the outersensor
surface on one of the door handles.
X To restore the factory settings: press
and hold down the 000Eand000D buttons
simultaneously for approximately six
seconds until the battery chec klamp
flashes twice ( Ypage 85). Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey, use the
mechanical key.
If you use the mechanical key to unlock and
open the driver's door or the trunk lid, the
anti-thef talarm system will be triggered
(Y page 78). There are several ways to tur
noff the alarm:
X To turn the alarm off with the
SmartKey: press the000Eor000D button
on the SmartKey.
or
X Insert the SmartKey into the ignition lock.
or
X To disarm the alarm with KEYLESS-GO:
press the Start/Stop button in the ignition
lock. The SmartKey must be in the vehicle.
or
X Lock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
Removing the mechanical key 0002
Release catch
0003 Mechanical key
X Push release catch 0002in the direction of
the arrow and at the same time remove
mechanical key 0003from the SmartKey.
For further information about:
R unlocking the driver's door (Y page 90)
R unlocking the trunk (Y page 93)
R locking the vehicle (Y page 90)84
SmartKeyOpening and closing 

SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive
substances. If batteries are swallowed, it can
result in severe health problems. There is a
risk of fatal injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop.
Checking the battery X
Press the 000Dor000E button.
The battery is working properly if battery
check lamp 0002lights up briefly.
The battery is discharged if battery check
lamp 0002does not light up briefly.
X Change the battery (Y page 85).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the 000Dor000E button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified
specialist workshop. Replacing the battery You require a CR 2025 3 V cell battery.
X
Take the mechanical key out of the
SmartKey (Y page 84). 0002
Battery compartment cover
0003 Mechanical key
X Press mechanical key 0003into the opening
in the SmartKey in the direction of the
arrow until battery compartment cover 0002
opens. Do not hold battery compartment
cover 0002closed while doing so.
X Remove battery compartment cover 0002. 0023
Battery
X Repeatedly tap the SmartKey against your
palm until battery 0023falls out.
X Insert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so. SmartKey
85Opening and closing Z 

Problems with the SmartKey
Problem Possible causes/consequences and
0001 Solutions
You can no longer lock
or unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Check the SmartKey battery (Y page 85) and replace it if
necessary (Y page 85).
If this does not work:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key.
X Have the SmartKey checked at a qualified specialist workshop. You can no longer lock
or unlock the vehicle
using KEYLESS-GO. The SmartKey battery is discharged or nearly discharged.
X
Check the SmartKey battery (Y page 85) and replace it if
necessary (Y page 85).
If this does not work:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. There is interference from a powerful source of radio waves.
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key. KEYLESS-GO is malfunctioning.
X
Lock/unlock the vehicle using the remote control function of
the SmartKey.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote
control function:
X Lock (Y page 90) or unlock (Y page 90) the vehicle using
the mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. You have lost a
SmartKey. X
Have the SmartKey deactivated at a qualified specialist
workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. SmartKey
87Opening and closing Z 

Problem Possible causes/consequences and
0001 Solutions
You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 332).
or
X Jump-start the vehicle (Y page 334).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. The vehicle is locked.
X
Unlock the vehicle and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle,
they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the vehicle. Always keep the SmartKey out of
reach of children.
G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines (Y page 288). Unlocking and opening doors from
the inside
! The side windows will not open/close if
the battery is discharged or if the side
windows have iced up. It will then not be
possible to close the door. Do not attempt
to force the door closed. You could 88
DoorsOpening and closing 

otherwise damage the door or the side
window.
You can open a door from inside the vehicle
even if it has been locked. If the vehicle has
been locked with the SmartKey or with
KEYLESS-GO, opening adoor from the inside
will trigger the anti-theft alarm system.
Switch off the alarm (Y page 78).X
To unlock a front door: pull door
handle 0003.
Locking knob 0002pops up.
The door is unlocked and can be opened.
X To open a front door: pull door
handle 0003.
X To unlock a rear door: pull up locking
knob 0002.
The door is unlocked and can be opened.
X To open a rear door: pull door handle0003.
i When a door is opened, the side window
on that side opens slightly. When the door
is closed, the side window closes again. Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. X
To unlock: press button 0002.
X To lock: press button 0003.
If all the doors are closed, the vehicle locks.
Meanwhile, the fuel filler flap will not be
locked or unlocked.
You cannot unlock the vehicle centrally from
the inside if the vehicle has been locked with
the SmartKey or KEYLESS-GO.
You can open a door from inside the vehicle
even if it has been locked.
If the vehicle has been locked using the
locking button for the central locking, or has
been locked automatically, and a door is
opened from the inside:
R the vehicle will be fully unlocked if it had
previously been fully unlocked
R only the door which has been opened form
the inside is unlocked if only the driver's
door had been previously unlocked Automatic locking feature Doors
89Opening and closing Z 

X
To deactivate: press and hold button 0002
for abou tfive seconds until a tone sounds.
X To activate: press and hold button 0003for
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.
The vehicle is locked automatically when the
ignition is switched on and the wheels are
turning.
You could therefore lock yourself out if:
R the vehicle is being pushed.
R the vehicle is being towed.
R the vehicle is on a roller dynamometer.
You can also switch the automatic locking
function on and off using the on-board
computer (Y page 245). Unlocking the driver's door
(mechanical key)
If the vehicle can no longer be unlocked with
the SmartKey, use the mechanical key.
X Take the mechanical key out of the
SmartKey (Y page 84).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 0006
To unlock X
Turn the mechanical key counter-clockwise
to position 0006.
The door is unlocked.
X Turn the mechanical key back and remove
it.
X Insert the mechanical key into the
SmartKey.
If you use the mechanical key to unloc kand
open the driver's door, the anti-thef talarm
system will be triggered ( Ypage 78). 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 and the
trunk lid.
X Press the locking button (Y page 89).
X Check whether the locking knob on the
front-passenger door is still visible. If
necessary, press the locking knob down by
hand (Y page 88).
X Close the driver's door.
X Take the mechanical key out of the
SmartKey (Y page 84).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 0006
To lock
X Turn the mechanical key clockwise as far
as it will go to position 0006.
X Turn the mechanical key back and remove
it. 90
DoorsOpening and closing 

X
Make sure that the doors and the trunk lid
are locked.
X Insert the mechanical key into the
SmartKey. Trunk
Important safety notes
G
WARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Exhaust
gases can enter the vehicle interior if the
trunk lid is open when the engine is running,
especially if the vehicle is in motion. There is
a risk of poisoning.
Always switch off the engine before opening
the trunk lid. Never drive with the trunk lid
open. G
WARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
i Opening dimensions of the trunk lid
(Y page 390).
You should preferably place luggage or loads
in the cargo compartment. Observe the
loading guidelines (Y page 288).
Do not leave the SmartKey in the trunk. You
could otherwise lock yourself out.
The trunk lid can be:
R opened and closed manually from outside
R opened automatically from outside
R opened automatically from inside
R locked separately
R opened with the emergency release button
R unlocked with the mechanical key Trunk lid reversing feature
The trunk lid is equipped with an automatic
reversing feature. It reacts if a solid object
obstructs or restricts the trunk lid during the
closing procedure. The trunk lid opens again
automatically .The automatic reversing
feature is only an aid and is not a substitute
for your attentiveness to the trunk lid while it
is closing. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last 1/3 in(8 mm) of the closing
movement
This means that the reversing feature cannot
prevent someone being trapped in these
situations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure.
If somebody becomes trapped:
R press the 0005button on the SmartKey, or
R press the remote operating switch on the
driver's door, or
R press the closing or locking button on the
trunk lid, or
R pull on the trunk lid handle Opening/closing from outside
Opening Trunk
91Opening and closing Z