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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. A child'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
If you attach heavy or large objects to the
SmartKey, the SmartKey could be
unintentionally turned in the ignition lock. This
could cause the engine to be switched off.
There is a risk of an accident.
Do not attach any heavy or large objects to
the SmartKey. Remove any bulky key rings
before inserting the SmartKey into the
ignition lock.
! Keep the SmartKey away from strong
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations. :
& To lock the vehicle
; F To unlock the trunk lid
= % To unlock the vehicle
The turn signals flash once when unlocking
and three times when locking.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 159).
X To unlock centrally: press the%
button.
If you do not open the vehicle within
approximately 40 seconds of unlocking:
R the vehicle is locked again.
R the anti-theft alarm system is armed again.
X To lock centrally: press the&button. Changing the settings of the locking
system
You can change the setting of the locking
system in such a way that only the driver's
door and the fuel filler flap are unlocked. This
is useful if you frequently travel on your own.
X To change the setting: press and hold
down the %and& buttons
simultaneously for approximately six
seconds until the battery check lamp
(Y page 65) flashes twice . SmartKey
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The SmartKey now functions as follows:
X
To unlock the driver's door: press the
% button once.
X To unlock centrally: press the%
button twice.
X To lock centrally: press the&button. Restoring the factory settings
X Press the %and& buttons
simultaneously for approximately six
seconds until the battery check lamp
flashes twice. 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, the anti-theft alarm
system will be triggered (Y page 58).
There are several ways to turn off the alarm:
X Press the %or& button on the
SmartKey.
or
X Insert the SmartKey into the ignition lock.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch :in the direction of
the arrow and at the same time remove
mechanical key ;from the SmartKey. 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. H
Environmental note Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment. Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified
specialist workshop or a
special collection point for
used batteries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National
guidelines must be observed during disposal.
In California, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop. 64
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Checking the battery
X
Press the &or% button.
The SmartKey battery is working properly if
battery check lamp :lights up briefly.
If battery check lamp :does not light up
briefly during the test, the SmartKey battery
is discharged.
X Change the battery (Y page 65).
i If the SmartKey battery is checked within
the signal reception range of the vehicle,
pressing the &or% button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified
specialist workshop.
Replacing the battery X
Take the mechanical key out of the
SmartKey (Y page 64).
You require a CR 2025 3 V cell battery. X
Press mechanical key ;into the opening
in the SmartKey in the direction of the
arrow until battery tray cover :opens. Do
not hold the cover closed while doing so. X
Remove the cover of the battery tray.
X Repeatedly tap the SmartKey against your
palm until battery =falls out.
X Insert the new battery with the positive
terminal facing upwards. Use a lint-free
cloth to do so.
X Insert the front tabs of the battery tray's
cover first, and then press to close it.
X Check the function of all SmartKey buttons
on the vehicle. SmartKey
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Problems with the SmartKey
Problem Possible causes/consequences and
M
MSolutions You cannot lock or
unlock the vehicle
using the SmartKey. The SmartKey battery is discharged or nearly discharged.
X
Point the tip of the SmartKey at the driver's door handle from
close range. Try to unlock or lock the vehicle again.
If this does not work:
X Unlock the vehicle using the mechanical key (Y page 64).
X Check the SmartKey battery and replace it if necessary
(Y page 65). The SmartKey is faulty.
X
Lock or unlock the vehicle using the mechanical key
(Y page 64).
X Have the SmartKey checked at a qualified specialist workshop. You have lost a
SmartKey. X
Have the SmartKey canceled at an authorized Mercedes-Benz
Center.
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. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. A door 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. 66
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Problem Possible causes/consequences and
M
MSolutions 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.
X Remove the SmartKey and reinsert it into the ignition lock.
X Start the engine within 30 seconds of inserting the SmartKey
into the ignition lock.
X Repeat if necessary.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 236).
or
X Jump-start the vehicle (Y page 240).
or
X Consult a qualified specialist workshop. The SmartKey cannot
be turned in the ignition
lock. The SmartKey has been in position
0for a considerable time.
X Remove the SmartKey and reinsert it into the ignition lock.
X Check the starter battery and charge it if necessary
(Y page 236).
X Start the engine. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to turn the SmartKey again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 236).
or
X Jump-start the vehicle (Y page 240).
or
X Consult a qualified specialist workshop. SmartKey
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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
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. A child'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
If objects, luggage or loads are not secured or
not secured sufficiently, they could slip, tip
over or be flung around and thereby hit vehicle
occupants. There is a risk of injury,
particularly in the event of sudden braking or
a sudden change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey. Unlocking and opening the doors
from the outside
Coupe !
The doors swing upwards and out when
opened. Therefore, make sure that there is
sufficient clearance above the vehicle. 68
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X
To open the door: point the SmartKey
towards door handle :.
X Press the %button on the SmartKey.
Door handle :moves out.
X Lift the door by door handle :and swing
it up as far as it will go.
X To close the door: pull the door
downwards by the outer edge or the interior
door handle. Swing the door down gently
and allow it to engage in the lower position.
X Lock the vehicle with the SmartKey if
necessary (Y page 62).
Roadster X
To open the door: point the SmartKey
towards door handle.
X Press the %button on the SmartKey.
The door is unlocked and can be opened.
X Pull the door handle. Unlocking and opening doors from
the inside
Coupe You can only open a door from the inside if it
is unlocked.
The vehicle locks the doors automatically if
you drive faster than 9 mph (15 km/h).
The doors are automatically unlocked after a
journey if you switch off the engine.
! The doors swing upwards and out when
opened. Therefore, make sure that there is
sufficient clearance above the vehicle. X
To unlock the door manually: press
the % button of central locking =.
or
X Pull locking knob :upwards.
X To open the door: pull handle;.
X Swing the door upwards as far as it will go.
X To close the door: pull the door down by
handle ?.
X Allow the door to engage in the lower
position.
X To lock the door manually: press
the & button of central locking =.
or
X Push locking knob :downwards.
Roadster You can open a door from inside the vehicle
even if it has been locked.
Only open the door when the traffic situation
permits. Doors
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X
Pull door handle ;.
If the door is locked, locking knob :pops
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.
! 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. Centrally locking and unlocking the
vehicle from the inside
You can centrally lock or unlock the vehicle
from the inside. This feature may be useful if,
for example, you wish to unlock the front-
passenger door from the inside or lock the
vehicle before you pull away.
Coupe: the central locking/unlocking button
does not lock or unlock the fuel filler flap.
Roadster: the central locking/unlocking
button does not lock or unlock the fuel filler
flap or the stowage compartments, such as
the glove box. X
To lock: press button ;.
If both doors are closed, the vehicle locks.
X To unlock: press button :. You can open a door from inside the vehicle
even if it has been locked. Only open the door
when the traffic situation permits.
If the vehicle has been locked with the central
locking button:
R
and the SmartKey is set to its factory
setting, the entire vehicle is unlocked if a
door is opened from the inside.
R and the SmartKey is set to an individual
setting, only the door that is opened from
inside the vehicle is unlocked. Automatic locking feature
Coupe You can only open a door from the inside if it
is unlocked.
The vehicle locks the doors automatically if
you drive faster than 9 mph (15 km/h).
The doors are automatically unlocked after a
journey if you switch off the engine.
Roadster
The vehicle is locked automatically when the
ignition is switched on and the vehicle's
wheels are moving at a speed in excess of
9 mph
(15 km/h). There is therefore a risk of
being locked out when the vehicle is being
pushed, towed or tested on a 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. 70
DoorsOpening and closing