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The spinning of the wheels results in a cut for
better traction on loose surfaces.
Rtraction control is still activated
RAdaptive Brake Assist is unavailable
Active Brake Assist is also not activated if you
brake firmly with assistance from ESP
®.
RPRE-SAFE®is unavailable
PRE-SAFE®is also not activated if you brake
firmly with assistance from ESP®.
RESP®still provides support when you brake
firmly
EBD (electronic brake force distribu-
tion)
General information
EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 57).
GWARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the
risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (
Ypage 196) as well as display
messages (Ypage 172).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety and
offers increased braking comfort. In addition to
the braking function, ADAPTIVE BRAKE also fea-
tures the hill start assist function (
Ypage 107).
Protection against theft
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
XTo activate with KEYLESS-GO start-func-
tion or KEYLESS-GO: switch the ignition off
and open the driver's door.
XTo activate with the SmartKey: remove the
SmartKey from the ignition lock.
XTo 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.
iThe 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)
XTo arm: lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp :flashes. The alarm system
is armed after approximately 15 seconds.
XTo disarm: unlock the vehicle with the Smart-
Key or KEYLESS-GO.
or
XWith KEYLESS-GO start function or vehi-
cles with KEYLESS-GO: press the Start/
Stop button.
The SmartKey must be in the vehicle.
Protection against theft63
Safety
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or
XInsert the SmartKey into the ignition lock.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
Ra door
Rthe vehicle with the mechanical key
Rthe tailgate
Rthe hood
XTo turn the alarm off with the SmartKey:
press the %or& button on the Smart-
Key.
The alarm is stopped.
or
XInsert the SmartKey into the ignition lock.
The alarm is stopped.
XTo stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or
XPress the Start/Stop button. The SmartKey
must be inside the vehicle.
The alarm is stopped.
The alarm is not switched off, even if you close
the open door that triggered it, for example.
iIf 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:
Ryou have subscribed to the mbrace service.
Rthe mbrace service has been activated
properly.
Rthe necessary mobile phone network is
available.
64Protection against theft
Safety
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SmartKey
Important safety notes
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart 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.
GWARNING
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:
Rwith electronic devices, e.g. a mobile phone
or another SmartKey
Rwith metallic objects, e.g. coins or metal foil
Rinside 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 on the cargo compart-
ment cover or in the cargo compartment. Oth-
erwise, 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:
Rwhen starting the engine
Rwhile driving
Rwhen using the tailgate unlocking sensor
Rwhen the external door handles are touched
Rduring convenience closing
SmartKey functions
:& Locks the vehicle
;FOpens the tailgate
=%Unlocks the vehicle
XTo unlock centrally: press the%button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
Rthe vehicle is locked again
Rthe anti-theft alarm system is armed again.
XTo lock centrally: press the&button.
The SmartKey centrally locks and unlocks the
doors and 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 via the
multimedia system; see the Digital Operator's
Manual.
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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.
Information on activating and deactivating the
locator lighting can be found in the Digital Oper-
ator's Manual.
XTo open the tailgate:press and hold the
F button until the tailgate opens.
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 (
Ypage 107).
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
& 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 check which periodically establishes a radio
connection between the vehicle and the Smart-
Key determines whether a valid SmartKey is in
the vehicle. This occurs, for example:
Rwhen starting the engine
Rwhile driving
Rwhen using the tailgate unlocking sensor
Rwhen the external door handles are touched
Rduring convenience closing
XTo unlock the vehicle: touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor surface :
or ;.
Make sure that you do not touch the inner
surface of the door handle.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
Further information on the convenience clos-
ing feature (
Ypage 77).
Deactivating and activating
If you do not intend to use the vehicle for a lon-
ger period of time, you can deactivate KEYLESS-
GO. The SmartKey will then use very little power,
thereby conserving battery power. For the pur-
poses of activation/deactivation, the vehicle
must not be nearby.
XTo deactivate: press the&button on the
SmartKey twice in rapid succession.
The indicator light on the SmartKey flashes
twice briefly then one long flash, then KEY-
LESS-GO is deactivated (
Ypage 68).
XTo activate: press any button on the Smart-
Key.
or
XInsert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features
are available again.
KEYLESS-GO start function
Bear in mind that the engine can be started by
any of the vehicle occupants if there is a Smart-
Key in the vehicle (
Ypage 107).
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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 travel
on your own.
XTo change the setting:press and hold down
the % and& buttons simultaneously
for about six seconds until the battery indica-
tor lamp flashes twice (
Ypage 68).
If the setting of the locking system is changed
within the signal range of the vehicle, pressing
the & or% button:
Rlocks or
Runlocks the vehicle
The SmartKey now functions as follows:
XTo unlock: press the%button once.
XTo unlock centrally: press the%button
twice.
XTo lock: press the &button.
The KEYLESS-GO functions can be changed as
follows:
XTo unlock the driver's door: touch the inner
surface of the door handle on the driver's
door.
XTo unlock centrally: touch the inner surface
of the front-passenger door handle.
XTo lock centrally: touch the outer sensor
surface on one of the door handles.
Restoring factory settings:
XPress the %and& buttons simultane-
ously for approximately six seconds until the
battery check lamp flashes twice
(
Ypage 68).
Mechanical key
General notes
If the vehicle can no longer be locked or
unlocked with the SmartKey or 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
(
Ypage 63). If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked auto-
matically.
XTo unlock the fuel filler flap:
insert the
SmartKey into the ignition lock.
Removing the mechanical key
XPush release catch :in the direction of the
arrow and at the same time remove mechan- ical key ;from the SmartKey.
For further information about:
Runlocking the driver's door (Ypage 72)
Rlocking the vehicle (Ypage 72)
Inserting the mechanical key
XPush mechanical key ;completely into the
SmartKey until it engages and release
catch :is back in its basic position.
SmartKey battery
Important safety notes
GWARNING
Batteries contain toxic and corrosive substan- ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatalinjury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
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HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separatelyand 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
XPress the &or% button.
The battery is working properly if battery
check lamp :lights up briefly.
The battery is discharged if battery check
lamp :does not light up briefly.
XChange the battery (Ypage 68). If the SmartKey battery is checked within the
signal reception range of the vehicle, pressing
the
& or% button:
Rlocks or
Runlocks the vehicle
iYou can get a battery at any qualified spe-
cialist workshop.
Replacing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the SmartKey
(Ypage 67).
XPress mechanical key ;into the SmartKey
opening in the direction of the arrow until bat-
tery compartment cover :opens. Do not
hold battery compartment cover :closed
while doing so.
XRemove battery compartment cover :.
XRepeatedly tap the SmartKey against your
palm until battery=falls out.
XInsert the new battery with the positive ter-
minal facing upwards. Use a lint-free cloth to
do so.
XMake sure that the surface of the battery is
free of lint, grease and other contaminants.
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XInsert the front tabs of battery compartment
cover:into the housing first and then press
to close it.XInsert mechanical key ;into the SmartKey
(Ypage 67).
XCheck the function of all SmartKey buttons on
the vehicle.
Problems with the SmartKey
ProblemPossible causes/consequences and MSolutions
You can no longer lock or
unlock the vehicle using
the SmartKey.The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 68) and replace it if necessary
(Ypage 68).
If this does not work:
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves.
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
The SmartKey is faulty.
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
XHave the SmartKey checked at a qualified specialist workshop.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO.KEYLESS-GO was deactivated.
XReactivate KEYLESS-GO (Ypage 66).
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 68) and replace it if necessary
(Ypage 68).
If this does not work:
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
There is interference from a powerful source of radio waves.
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
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ProblemPossible causes/consequences andMSolutions
KEYLESS-GO is malfunctioning.
XLock/unlock the vehicle using the remote control function of the
SmartKey.
XHave 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:
XUnlock (Ypage 72) or lock (Ypage 72) the vehicle using the
mechanical key.
XHave 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.
XSwitch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary (Ypage 251).
or
XJump-start the vehicle (Ypage 251).
or
XConsult 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.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 68) and replace it if necessary
(Ypage 68).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-
Key.XHave the SmartKey deactivated at a qualified specialist workshop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
You have lost the
mechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
70SmartKey
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