
Rearward-facing child restraint system
If circumstances require you to secure a child in
a rearward-facing child restraint system on the
front-passenger seat, always make sure that the front passenger front air bag is deactivated.
Only if the PASSENGER AIR BAG OFF indicator
lamp is lit continuously (Y page 43), is the front
passenger front air bag deactivated.
Always observe the child restraint system man- ufacturer's installation and operating instruc-
tions.
Forward-facing child restraint system If it is absolutely necessary to install a forward-
facing child restraint system on the front-
passenger seat, always move the front-
passenger seat as far back as possible. The
entire base of the child restraint system must
always rest on the seat cushion of the front-
passenger seat. The backrest of the child
restraint system must lie as flat as possible
against the backrest of the front-passenger
seat. The child restraint system must not touch the roof or be subjected to a load by the head
restraint. Adjust the angle of the seat backrest
and the head restraint position accordingly.
Always make sure that the shoulder belt strap is
correctly routed from the vehicle belt outlet to
the shoulder belt guide on the child restraint
system. The shoulder belt strap must be routed
forward and down from the vehicle belt outlet. If
necessary, adjust the vehicle belt outlet and the front-passenger seat accordingly.
Always observe the child restraint system man-ufacturer's installation and operating instruc-
tions. Child-proof locks
Important safety notes G
WARNING
If children are traveling in the vehicle, they
could:
R open doors, thus endangering other people
or road users
R exit the vehicle and be caught by oncoming
traffic
R operate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for:
R the rear doors (Y page 63)
R the rear side windows (Y page 63) G
WARNING
If you leave children unsupervised in the vehi- cle, they could set it in motion by, for example:
R release the parking brake.
R shift the automatic transmission out of the
parking position P.
R start the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle. 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. 62
Children in the vehicleSafety

No steering assistance is provided from STEER
CONTROL, if:
R ESP ®
is deactivated
R ESP ®
is malfunctioning
R the steering is malfunctioning
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering. Protection against theft
Immobilizer
X To activate with the SmartKey: remove the
SmartKey from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been left inside the vehicle.
i The immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started (yet the vehicle's battery is charged), the sys-
tem is not operational. Contact an authorized Mercedes-Benz Center or call
1-800 FOR-MERCEDES (in the USA) or
1-800-387-0100 (in Canada). ATA (anti-theft alarm system) X
To arm: lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp 0043flashes. The alarm system
is armed after approximately 15 seconds.
X To disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or X Insert the SmartKey into the ignition lock.
A visual and audible alarm is triggered if the
alarm system is armed and you open: R a door
R the vehicle with the mechanical key
R the tailgate
R the hood
X To switch the alarm off with the Smart-
Key:
press the 0036or0037 button on the
SmartKey.
The alarm is stopped.
or
X Remove the Start/Stop button from the igni-
tion lock.
X Insert the SmartKey into the ignition lock.
The alarm is stopped.
X To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or
X Press the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
The alarm is stopped.
The alarm is not switched off, even if you close
the open door that triggered it, for example.
i If the alarm continues for more than
30 seconds, the mbrace emergency call sys-
tem automatically notifies the Customer
Assistance Center. This is done either by text
message or data connection. The emergency call system sends the message or data provi-
ded that:
R you have subscribed to the mbrace service.
R the mbrace service has been activated
properly.
R the necessary mobile phone network is
available. Protection against theft
73Safety Z

SmartKey
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 you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally 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 mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin- ity of powerful electrical installations.
Do not keep the SmartKey: R with electronic devices, e.g. a mobile phone
or another SmartKey.
R with metallic objects, e.g. coins or metal foil.
R inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart- Key. Do not keep the KEYLESS-GO or KEYLESS-GO
Start function key in the temperature-controlled
cup holder. Otherwise, the KEYLESS-GO or KEY- LESS-GO Start function key will not be detected.
Vehicles with KEYLESS-GO start function: do
not keep the SmartKey in the cargo compart-
ment. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button. SmartKey functions
0043
0037 Locks the vehicle
0044 0054 Opens/closes the tailgate
0087 0036 Unlocks the vehicle
X To unlock centrally: press the0036button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
R the vehicle is locked again
R anti-theft protection is reactivated
X To lock centrally: press the0037button.
The SmartKey centrally locks and unlocks the
following components:
R the doors
R the tailgate
R the fuel filler flap
The turn signals flash once when 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 219).
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked. 74
SmartKeyOpening and closing

If activated in the multimedia system, the loca-
tor lighting also lights up in the dark (see the
Digital Operator's Manual).
X To open the tailgate automatically from
outside the vehicle: press and hold the0054
button until the tailgate opens.
Vehicles with KEYLESS-GO: X To close the tailgate automatically from
outside the vehicle:
if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the 0054button on the SmartKey.
When the tailgate closes you can then release
the button. KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a KEY-
LESS-GO key in the vehicle (Y page 129).
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 func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the 0037 button on the SmartKey.
The driver's door and the door at which the han- dle is used, must both be closed. The SmartKey
must be outside the vehicle. 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).
KEYLESS-GO checks whether a valid SmartKey
is in the vehicle by periodically establishing a
radio connection between the vehicle and the
SmartKey. This happens:
R when starting the engine
R while driving
R when the external door handles are touched
R during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle.
X To lock the vehicle: touch sensor surface 0043
or 0044.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface 0044for an extended
period.
Further information on the convenience closing
feature (Y page 87).
If you pull on the handle of the tailgate, only the cargo compartment of the vehicle is unlocked.
Deactivating and activating If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby.
X To deactivate: press the0037button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, KEY-
LESS-GO is deactivated (Y page 77).
X To activate: press any button on the Smart-
Key.
or X Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again. SmartKey
75Opening and closing Z

KEYLESS-GO start function
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (Y page 129).Changing the settings of the locking
system
You can change the settings of the locking sys-
tem. 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 travelalone.
X To change the setting: press and hold down
the 0036 and0037 buttons simultaneously
for about six seconds until the battery indica-
tor lamp flashes twice (Y page 77).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the 0037 or0036 button:
R locks or
R unlocks the vehicle
The SmartKey now functions as follows:
X To unlock: press the0036button once.
X To unlock centrally: press the0036button
twice.
X To lock centrally: press the0037button.
The KEYLESS-GO function is changed as fol-
lows:
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 door handle on the front-passenger
door or the rear door.
X To lock centrally: touch the outer sensor
surface on one of the door handles
(Y page 75).
X To restore the factory settings: press and
hold down the 0036and0037 buttons simul-
taneously for approximately six seconds until
the battery check lamp flashes twice
(Y page 77). Mechanical key
General notes If the vehicle can no longer be locked or
unlocked with the SmartKey or with KEYLESS-
GO, use the mechanical key.
If you use the mechanical key to unlock and
open the driver's door, the anti-theft alarm sys- tem will be triggered. Switch off the alarm
(Y page 73).
If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
X To unlock the fuel filler flap: insert the
SmartKey into the ignition lock.
Removing the mechanical key X
Push release catch 0043in the direction of the
arrow and at the same time remove mechan- ical key 0044from the SmartKey.
For further information about:
R Unlocking the driver's door (Y page 81)
R Unlocking the cargo compartment
(Y page 85)
R Locking the vehicle (Y page 81)
Inserting the mechanical key X
Push mechanical key 0044completely into the
SmartKey until it engages and release
catch 0043is back in its basic position. 76
SmartKeyOpening and closing

SmartKey battery
Important safety notes G
WARNING
Batteries contain toxic and corrosive substan- ces. 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 spe-
cialist workshop or a special
collection point for used bat-
teries.
The SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. National guide-
lines must be observed during disposal. In Cal-
ifornia, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/index.cfm.
Mercedes-Benz recommends that you have the
batteries replaced at a qualified specialist work- shop. Checking the battery X
Press the 0037or0036 button.
The battery is working properly if battery
check lamp 0043lights up briefly.
The battery is discharged if battery check
lamp 0043does not light up briefly.
X Change the battery (Y page 77).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 0037 or0036 button:
R locks or
R unlocks the vehicle
i You can get a battery at any qualified spe-
cialist workshop.
Replacing the battery You require a CR 2025 3 V cell battery.
X Take the mechanical key out of the SmartKey
(Y page 76). X
Press mechanical key 0044into the SmartKey
opening in the direction of the arrow until bat- tery compartment cover 0043opens. Do not
hold battery compartment cover 0043closed
while doing so.
X Remove battery compartment cover 0043. SmartKey
77Opening and closing Z

X
Repeatedly tap the SmartKey against your
palm until battery 0087falls out.
X Insert the new battery with the positive ter-
minal 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 0043into the housing first and then press
to close it.
X Insert mechanical key 0044into the SmartKey
(Y page 76).
X Check the function of all SmartKey buttons on
the vehicle. Problems with the SmartKey
Problem
Possible causes/consequences and
0050 0050Solutions 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 77) and replace it if necessary
(Y page 77).
If this does not work: X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key. There is interference from a powerful source of radio waves.
X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key. The SmartKey is faulty.
X Unlock (Y page 81) or lock (Y page 81) 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. KEYLESS-GO was deactivated.
X Reactivate KEYLESS-GO (Y page 75). The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 77) and replace it if necessary
(Y page 77).
If this does not work: X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key. 78
SmartKeyOpening and closing

Problem
Possible causes/consequences and
0050
0050Solutions There is interference from a powerful source of radio waves.
X Unlock (Y page 81) or lock (Y page 81) 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 con-
trol function:
X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. The engine cannot be
started using the Smart-
Key. 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 317).
or X Jump-start the vehicle (Y page 318).
or X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 77) and replace it if necessary
(Y page 77).
If this does not work: X Start your vehicle with the SmartKey in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the SmartKey in the ignition lock. You have lost a Smart-
Key. 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
79Opening and closing Z