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SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and caustic
substances. For this reason, keep batteries
out of the reach of children.
If a battery has been swallowed, seek medical
help immediately. G
WARNING
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Observe
governmen tdisposal guidelines. California
residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Mercedes-Ben zrecommends 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
chec klamp 0002lights up briefly.
The battery is discharged if battery check
lamp 0002does no tlight up briefly.
X Change the battery (Y page 87).i
If the SmartKey battery is checked within
the signal receptio nrange 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 86). X
Press mechanical key 0003intothe SmartKey
opening in the direction of the arrow until
battery compartment cover 0002opens. Do
not hold battery compartment cover 0002
closed while doing so.
X Remove battery compartment cover 0002. SmartKey
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Page 90 of 590
X
Repeatedly tap the SmartKey against your
palm until battery 0027falls out.
X Inser tthe new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.
X Make sure that the surface of the battery is
free of lint, grease and other contaminants.
X Insert the front tabs of battery
compartment cover 0002into the housing
first and then press to close it.
X Insert mechanical key 0003into the
SmartKey.
X Check the function of all SmartKey buttons
on the vehicle. 88
SmartKeyOpening and closing
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Problems with the SmartKey
Problem Possible causes/consequences and
0003 Solutions
You cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Try again to lock/unlock the vehicle using the remote control
function of the SmartKey. Point the tip of the SmartKey at the
driver's door handle from close range and press the 000Eor
000D button.
If this does not work:
X Check the SmartKey battery (Y page 87) and replace it if
necessary (Y page 87).
X Lock (Y page 92) or unlock (Y page 93) the vehicle using
the mechanical key. The SmartKey is faulty.
X
Unlock (Y page 92) or lock (Y page 93) 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. There is interference from a powerful source of radio waves.
X Lock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the 000Eor000D button. There is a malfunction with KEYLESS-GO.
X Lock/unlock the vehicle using the remote control function of
the SmartKey. Point the tip of the SmartKey at the driver's door
handle from close range and press the 000Eor000D button.
X Have KEYLESS-GO checked at a qualified specialist workshop.
If this does not work:
X Check the SmartKey battery (Y page 87) and replace it if
necessary (Y page 87).
X Lock (Y page 92) or unlock (Y page 93) the vehicle using
the mechanical key. 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. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. SmartKey
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Problem Possible causes/consequences and
0003 Solutions
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 533).
or
X Jump-start the vehicle (Y page 534).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. Ad
oor is open. Therefore, the SmartKey cannot be detected as
easily.
X Close the door 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
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function. If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger compartmentu nless they are
firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of:
R strong braking maneuvers
R sudden changes of direction
R an accident 90
DoorsOpening and closing
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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
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 was previously locked with the
SmartKey or with KEYLESS-GO, opening the
vehicle from the inside will activate the anti-
theft alarm system. Switch off the alarm
(Y page 81). X
Pull door handle 0003.
If the door is locked, locking knob 0002pops
up. The door is unlocked and can be
opened.
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. For example, you can unlock
the front-passenger door from the inside or
lock the vehicle before you pull away. X
To unlock: press button 0002.
X To lock: press button 0003.
If the front-passenger door is closed, the
vehicle locks.
The central locking/unlocking button does
not lock or unlock the fuel filler flap or the
stowage compartments, such as the glove
box.
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 Doors
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Automatic locking feature
0002
Disarming
0003 Arming
X To disarm: press and hold button 0002for
about five seconds until a tone sounds.
X To arm: press and hold button 0003for about
five seconds until a tone sounds.
i If you press one of th etwo buttons and
do not hear a tone, the relevant setting has
already been selected.
The vehicle is locked automatically when the
ignitio nis switched on and the wheels are
turning.
You could therefore lock yourselfo ut 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 235). Power closing feature
G
WARNING
To preven tpossible personal injury, always
keep hands and fingers away from the door or
trunk opening when closing a door or the
trunk lid. Be especially careful when small
children are around.
If danger threatens, pull the inside or outside
door handle, or pull the trunk lid handle. To prevent personal injury, never activate the
closing assist mechanism by tampering with
the door or trunk lid latch. G
WARNING
Only drive with the doors closed. Otherwise,
one or more of the doors could open while the
vehicle is in motion, putting you and/or
others at risk. G
WARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
The power closing feature pulls the doors and
trunk lid into their locks automatically even if
they are only partly closed.
X Power closing feature (doors): push the
door past the first detent position of the
lock.
The power closing feature will pull the door
fully closed.
X Power closing feature (trunk lid): lightly
push the trunk lid closed.
The power closing feature will pull the trunk
lid fully closed. 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 81).
X Take the mechanical key out of the
SmartKey (Y page 86).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 92
DoorsOpening and closing
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X
Turn the mechanical key counter-clockwise
to position 0007.
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 and the
trunk lid.
X Press the locking button (Y page 91).
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 91).
X Close the driver's door.
X Take the mechanical key out of the
SmartKey (Y page 86).
X Insert the mechanical key into the lock of
the driver's door as far as it will go. 0007
Locking
X Turn the mechanical key clockwise as far
as it will go to position 0007.
X Turn the mechanical key back and remove
it.
X Make sure that the doors and the trunk lid
are locked.
X Insert the mechanical key into the
SmartKey.
i If you lock the vehicle as described above,
the fuel filler flap is not locked. The anti-
theft alarm system is not armed. Trunk
Important safety notes
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the Trunk
93Opening and closing
Z
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seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident G
WARNING
Make sure the trunk lid is closed when the
engine is running and while driving. Among
other dangers, deadly carbon monoxide (CO)
gases may enter the vehicle interior resulting
in unconsciousness and death.
! The trunk lid swings upwards when
opened. Therefore, make sure that there is
sufficient clearance above the trunk lid.
! Only close the trunk once the roof is
lowered completely. Otherwise, you could
damage the roof.
If you close the trunk lid before the roof is
lowered completely, the loading aid switch
lights up and a warning tone sounds.
i Opening dimensions of the trunk lid
(Y page 585).
i To make loading easier, the stowed roof
can be raised with the loading aid after the trunk lid has been opened. The trunk
partition can also be detached. The trunk
partition must be closed againa
fter
loading. Otherwise, the roof cannot be
lowered.
You can unlock the trunk lid if the vehicle is
stationary and the roof is completely open or
closed.
Do not leave the SmartKey in the trunk. You
could otherwise lock yoursel fout.
The trunk lid can be:
R opened and closed from outside
R opened automatically from outside
(vehicles without trunk lid remote closing
feature)
R opened and closed automatically from
outside (vehicles with trunk lid remote
closing feature)
R opened and closed from outside (vehicles
with KEYLESS-GO and HANDS-FREE
ACCESS)
R opened and closed automatically from
inside (vehicles with trunk lid remote
closing feature)
R locked separately
R unlocked with the mechanical key
R opened with the emergency release button Opening/closing from outside
Opening 94
TrunkOpening and closing