
Forward-facing child restraint system Always mov e th e front-passenger's seat as far
bac k as possible if th e child must be secured on
th e front-passenger seat in a forward-facing
child restrain t system. Full y retrac t th e seat
cushion length. The base of th e child restrain t
system must always res t on th e seat cushion of
th e front-passenger's seat . As muc h as possible
of th e backrest of th e child restrain t system
must be resting on th e backrest of th e front-
passenger's seat . The child restrain t system
may no t touch th e roo f or be subjected to a load
by th e head restraint. Adjus t th e angle of th e
seat backrest and th e head restraint position
accordingly. Always mak e sure th e shoulder belt
is correctly secured , runnin g from th e belt outlet
to th e belt guide of th e child restrain t system.
The shoulder belt strap must be routed forward
and down from th e vehicl e belt outlet . Adjus t th e
belt outlet and front-passenger seat as required.
Always comply wit h th e manufacturer' s instal -
lation and operating instruction s for th e child
restrain t system.
Child-proof locks
Important safety notes
G WARNIN G
If children are traveling in th e vehicle, they
could: R
open doors, thus endangering other people
or road user sR
exit th e vehicl e and be caught by oncomin g
traffic R
operate vehicl e equipmen t and become
trapped
Ther e is a ris k of an acciden t and injury.
Always activat e th e child-proof locks and
override feature if children are traveling in th e
vehicle. When leaving th e vehicle, always tak e
th e ke y wit h you and loc k th e vehicle. Never
leav e children unattended in th e vehicle.
Override feature for :R
th e rear door s ( Y
page 64)R
th e rear side windows ( Y
page 64) G WARNIN G
If you leav e children unsupervised in th e vehi-
cle , they could set it in motion by, for example :R
release th e parking brake. R
shif t th e automatic transmission out of th e
parking position P . R
start th e engine.
In addition , they may operate vehicl e equip-
men t and become trapped . Ther e is a ris k of
an acciden t and injury.
When leaving th e vehicle, always tak e th e
SmartKey wit h you and loc k th e vehicle. Never
leav e children unsupervised in th e vehicle.
G WARNIN G
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a ris k of injury, possibly eve n
fatal. Never leav e children unattended in th e
vehicle.
G WARNIN G
If th e child restraint system is subjected to
direct sunlight, part s may get ver y hot . Chil-
dre n may burn themselve s on these parts,
particularly on th e metal part s of th e child
restraint system. Ther e is a ris k of injury.
If you leav e th e vehicle, taking th e child wit h
you, always ensure that th e child restraint
system is no t expose d to direct sunlight. Pro -
tect it wit h a blanket, for example . If th e child
restraint system has been expose d to direct
sunlight, let it cool down before securin g th e
child in it . Never leav e children unattended in
th e vehicle.Children in the vehicle 63
Safety Z

Protection against theft
Immobilizer The immobilizer prevents your vehicle from
being started without the correct SmartKey. X
To activate with the SmartKey: remove the
SmartKey from the ignition lock. X
To activate with KEYLESS-GO start-func-
tion or KEYLESS-GO: switch the ignition off
and open the driver's door. X
To deactivate: switch on the ignition.
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 C flashes. The alarm system
is armed after approximately ten seconds. X
To disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or X
Insert the SmartKey into the ignition lock.
or X
Press the Start/Stop button.
The SmartKey must be in the vehicle. 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 stop the alarm with the SmartKey:
press the 6 or 7 button on the Smart-
Key.
The alarm is stopped.
or X
Remove the Start/Stop button from the igni-
tion lock ( Y
page 133). 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 a message
or establishes a data connection provided
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.76
Protection against theft
Safety

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 PR
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. 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.
A brief radio connection between the vehicle
and the SmartKey determines whether a valid
SmartKey is in, or in the direct vicinity of, the
vehicle. This occurs, for example: R
when starting the engine R
while driving R
when using HANDS-FREE ACCESS R
when the external door handles are touched R
during convenience closing
SmartKey functions
C
7 Locks the vehicle D
T Opens/closes the tailgate

multimedia system; see the Digital Operator's
Manual.
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked.
When the locator lighting is activated via the
multimedia system, it lights up when it is dark
after the vehicle is unlocked with the SmartKey;
see the Digital Operator's Manual. X
To open the tailgate automatically from
outside the vehicle: press and hold the T
button until the tailgate opens. 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 T button 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 Smart-
Key in the vehicle ( Y
page 134).
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
7 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).
A brief radio connection between the vehicle
and the SmartKey determines whether a valid
SmartKey is in, or in the direct vicinity of, the
vehicle. This occurs, for example: R
when starting the engine R
while driving R
when using HANDS-FREE ACCESS 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 C
or D .
Make sure that you do not touch the inner
surface of the door handle. X
Convenience closing feature: touch
recessed sensor surface D for an extended
period.
Further information on the convenience clos-
ing feature ( Y
page 91). X
To unlock the tailgate: pull the tailgate han-
dle.
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 the 7 button on the
SmartKey twice in rapid succession.
The battery check lamp ( Y
page 80) of the
SmartKey flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated. 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.78
SmartKey
Opening and closing

KEYLESS- GO start function
Gene ra l notesBear in min d that th e engin e can be started by
any of th e vehicl e occupant s if there is a Smart -
Key in th e vehicl e ( Y
page 134).
Changing the settings of the locking
system You can chang e th e setting s of th e locking sys-
tem. This mean s that only th e driver's door and
th e fuel filler flap are unlocke d when th e vehicl e
is unlocked. This is useful if you frequentl y travel
alone. X
To change th e setting: press and hold down
th e 6 and 7 buttons simultaneousl y
for approximately six seconds until th e bat -
tery chec k lamp ( Y
page 80) flashes twice .
If th e setting of th e locking system is changed
within th e signal range of th e vehicle, pressing
th e 7 or 6 button:R
locks or R
unlocks th e vehicl e
The SmartKey no w function s as follows :X
To unlock: press th e 6 butto n once .X
To unlock centrally: press th e 6 butto n
twice .X
To lock: press th e 7 button.X
To restor e th e factory settings: press and
hold th e 6 and 7 buttons simultane -
ousl y for approximately six seconds until th e
battery chec k lamp ( Y
page 80) flashes
twice .
The KEYLESS-GO function s can be changed as
follows :X
To unlock th e driver's door : touch th e inner
surfac e of th e door handle on th e driver's
door .X
To unlock centrally: touch th e inner surfac e
of th e door handle on th e front-passenger
door or th e re ar door .X
To lock centrally: touch th e outer sensor
surfac e on on e of th e door handles . Mechanical key
Gene ra l notesIf th e vehicl e can no longer be locke d or
unlocke d wit h th e SmartKey or KEYLESS-GO ,
use th e mechanical key.
If you use th e mechanical ke y to unloc k and
open th e driver's door , th e anti-thef t alarm sys-
te m will be triggered . Switc h off th e alarm
( Y
page 76) .
If you unloc k th e vehicl e usin g th e mechanical
key, th e fuel filler flap will no t be unlocke d auto -
matically. X
To unlock th e fuel filler flap: insert th e
SmartKey int o th e ignition lock.
Removing the me chanical key
X
Push release catch C in th e direction of th e
arrow and at th e sam e time remove mechan -
ical ke y D from th e SmartKey.
Fo r further information about :R
Locking/unlocking th e driver's door
( Y
page 84 ) R
Unlocking th e tailgat e ( Y
page 89 )
Inserting the me chanical key X
Push mechanical ke y D completely int o th e
SmartKey until it engage s and release
catch C is bac k in it s basic position .SmartKey 79
Opening and closing Z

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 7 or 6 button.
The battery is working properly if battery
check lamp C lights up briefly.
The battery is discharged if battery check
lamp C does not light up briefly. X
Change the battery ( Y
page 80).
If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the 7 or 6 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 79).
X
Press mechanical key D into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover C opens. Do not
hold battery compartment cover C closed
while doing so. X
Remove battery compartment cover C .80
SmartKey
Opening and closing