
The PRE-SAFE®
system takes preventive
measures to better protect the occupants
from the possibility of personal injuries in the
following hazardous situations:
R emergency braking maneuvers with the
Brake Assist System (BAS) ( Y page 63)
activated
R critical dynamic driving situations, e.g.
when the vehicle has been caused to
understeer or oversteer because it has
exceeded its physical limitations or in case
of evasive steering maneuvers at speeds
above approximately 85 mph (140 km/h)
PRE-SAFE ®
takes the following measures
when it is activated:
R The front seat belts are pre-tensioned
automatically.
R Vehicles with front passenger seat memory
function: If the passenger seat is in an
unfavorable position, the seat will be
adjusted to a position that seeks to better
protect the occupant.
R If the vehicle is in a critical dynamic driving
situation, the door windows close, except
for a minimal gap that remains open.
R Vehicles with power tilt/sliding sunroof: If
the vehicle is in a critical dynamic driving
situation, the tilt/sliding sunroof also
closes, except for a minimal gap that
remains open.
If the closing procedure of any of these
elements is blocked, it will stop and open
slightly.
Once the hazardous situation no longer exists
and an accident has been avoided, the seat
belt pre-tensioning is deactivated. All of the
PRE-SAFE ®
settings can be re-adjusted
following the critical driving event.
If the seat belts do not release:XAdjust the seat backrest or seat slightly to
the rear until the seat belt tension is
reduced.
The locking mechanism releases.! When moving the seats, make sure there
are no items in the footwell or behind the
seats. Otherwise, you could damage the
seats and/or the items.
For information on the seat belt adjustment
function as an integrated comfort feature of
PRE-SAFE ®
, see ( Y page 51).
NECK-PRO active front head
restraints
The NECK-PRO active front head restraints
are intended to offer the driver and front
passenger increased protection from
whiplash-type injuries. In the event of a rear-
end collision, the NECK-PRO active front head
restraints on the front seats are designed to
move forward in the direction of travel. They
thus provide the head with increased support
earlier on in the collision sequence. The
NECK-PRO active front head restraints will
move forward whether the seats are occupied
or not.
GWarning!
Do not attach any objects (e.g. hangers) to the
head restraint posts. Otherwise, the NECK-
PRO active front head restraints may not be
able to function properly or offer the intended
degree of protection they were designed for
in the event of a rear-end collision.
GWarning!
Only use seat or head restraint covers which
have been tested and approved by Mercedes-
Benz for your vehicle model.
Using other seat or head restraint covers may
interfere with or prevent the activation of the
NECK-PRO active front head restraints and/
or the deployment of the front side impact air
bags.
Contact an authorized Mercedes-Benz Center
for availability.
When the NECK-PRO active front head
restraints have been triggered in an accident,
the NECK-PRO active front head restraints
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Make sure:
R The seat belt is always fitted snugly.
R Adjust the seat belt so that the shoulder
section is located as close as possible to
the middle of the shoulder.
R Place the lap portion of the seat belt as low
as possible on your hips.
Seat and head restraintGObserve Safety notes, see page 81.XPosition seat = and head restraint
properly. See ( Y page 82) for seat and
head restraint adjustment.
Observe the following points:
R Always be in a properly seated position.
R The position should be as far rearward from
the front air bag in the steering wheel as
possible, while still permitting proper
operation of vehicle controls.
R Adjust the seat to a comfortable seating
position that still allows you to reach the
accelerator/brake pedal safely.
R The seat must be adjusted so that you can
correctly fasten and position your seat belt.
R The seat backrest must be in a position that
is as nearly upright as possible.
R Adjust the seat cushion so that the front
edge of the seat cushion lightly supports
your legs.
R Adjust the head restraint so that it is as
close to the head as possible and the
center of the head restraint supports the
back of the head at eye level.
R Never place hands under the seat or near
any moving parts while the seat is being
adjusted.
Children in the vehicle
Safety notes
If an infant or child is traveling with you in the
vehicle:
XSecure the child using an infant or child
restraint appropriate to the age and size of
the child.XMake sure the infant or child is properly
secured at all times while the vehicle is in
motion.GWarning!
When leaving the vehicle, always remove the
SmartKey from the starter switch. Always
take the SmartKey with you and lock the
vehicle. Do not leave children unattended in
the vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child’s unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
starter switch or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the child could be burned by these
parts.
GWarning!
Do not carry heavy or hard objects in the
passenger or cargo compartment unless they
are firmly secured in place.
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XInstall a LATCH-type child seat according
to the manufacturer’s instructions.
A rigid connection between the child seat
and the body of the vehicle is established.
XMake sure that the seat belt for the rear
center seat can operate freely with a child
seat installed.
Child safety
Child safety locks
GObserve Safety notes, see page 55.GWarning!
Children could open a rear door from the
inside. This may cause serious personal injury
or an accident. Therefore, secure the rear
doors with the child safety locks whenever
children are riding in the back seats of the
vehicle.
The child safety locks on the rear doors
enable you to secure each rear door
individually. You cannot open a secured rear
door from the inside. You can open the rear
door from the outside when the vehicle is
unlocked.
XSecuring: Press the lever down in direction
of arrow ;.
XCheck to make sure the child safety locks
are working properly.
XReleasing: Press the lever up in direction
of arrow :.
Override switch
GObserve Safety notes, see page 55.
With the override switch you can disable the
rear door window switches in the rear door
panels. This can be useful, for instance, when
you have children riding in the rear passenger
compartment.
GWarning!
Activate the override switch when children
are riding in the back seats of the vehicle. The
children may otherwise injure themselves,
e.g. by becoming trapped in the rear door
window opening.
XActivating: Press override switch :.
The switch engages in recessed position.
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over-/understeering, thus improving vehicle
traction.
ESP ®
trailer stabilization
If the trailer you are towing should begin to
sway, the rig can only be stabilized by
immediately applying the brakes hard.
Steering during this maneuver will not help to
stabilize the rig.
The ESP ®
will assist you in such situations.
The ESP ®
recognizes when the trailer starts
swaying and will apply the brakes to reduce
the vehicle speed to a non-critical speed that
allows the vehicle-trailer combination to
stabilize.
The ESP ®
trailer stabilization is functional at
vehicle speeds above approximately 40 mph
(65 km/h) when the ESP ®
is switched on.
GWarning!
The system will not be able to assist when the
trailer jackknifes
R if the ESP ®
has switched off due to a
malfunction
R on wet or icy roads
R on roads with slippery surface
R in sand or gravel
Trailers with a high center of gravity may tip
over before the system recognizes swaying of
the trailer.
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
ActivatingXWith SmartKey: Remove the SmartKey
from the starter switch.XWith KEYLESS-GO: Turn off the engine and
open the driver’s door.
Deactivating
XSwitch on the ignition.
i Starting the engine will also deactivate
the immobilizer.
In the event that the engine cannot be
started (yet the vehicle’s battery is
charged), the system 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).
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
R a door
R the tailgate
R the hood
The alarm will stay on even if the activating
element, a door, for example, is closed
immediately.
The alarm system will also be triggered when
R the vehicle is opened with the mechanical
key
R a door is opened from the inside
To cancel the alarm after it has been
triggered, see “Canceling the alarm”
( Y page 67).
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iIf the alarm stays on for more than
30 seconds, the Tele Aid system initiates a
call to the Response Center automatically.
The Tele Aid system will initiate the call
provided that
Ryou have subscribed to the Tele Aid
service
Rthe Tele Aid service has been activated
properly
Rthe necessary mobile phone, power
supply and GPS coverage are available
XArming: Lock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash three times to
indicate that the vehicle is locked. Indicator
lamp : flashes to indicate that the alarm
system is armed.
iIf the turn signal lamps do not flash three
times, a door or the tailgate may not be
properly closed.
Close the respective element.
XDisarming: Unlock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash once to indicate
that the alarm system is disarmed.
iUnless you open a door or the tailgate
within approximately 40 seconds after
unlocking the vehicle:
RThe vehicle will be locked again.
RThe anti-theft alarm system will be
rearmed.
Canceling the alarm
To cancel the alarm, do one of the following:
XInsert the SmartKey into the starter switch.XPress button % or & on the
SmartKey.
In vehicles with KEYLESS-GO:
XGrasp an outside door handle.
The SmartKey must be within 3 ft (1 m) of
the vehicle.
XPress the KEYLESS-GO start/stop button.
The SmartKey must be inside the vehicle.
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iCanada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Factory setting XGlobal unlocking: Press button %.
Unless you open a door or the tailgate within
approximately 40 seconds after unlocking
the vehicle:
R The vehicle will be locked again.
R The antitheft alarm system will be rearmed.
XGlobal locking: Press button &.
Selective setting
If you frequently travel alone, you may wish
to reprogramm the SmartKey. Pressing
button % will then only unlock the driver’s
door and the fuel filler flap.
XSwitching on/off: Press and hold buttons
% and & simultaneously for
approximately 6 seconds until the battery
check lamp ( Y page 73) flashes twice.
The SmartKey will then function as follows:
XUnlocking driver’s door and fuel filler
flap: Press button % once.XGlobal unlocking: Press button %
twice.XGlobal locking: Press button &.KEYLESS-GO
Vehicles equipped with KEYLESS-GO come
with two SmartKeys with KEYLESS-GO, each
with remote control and a removable
mechanical key.
The KEYLESS-GO function is integrated into
the SmartKey. The validity of the SmartKey is
checked every time you grasp an outside door
handle.
When the SmartKey is valid, your vehicle
unlocks
R the doors
R the fuel filler flap
R the tailgate
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful interference, and
2. this device must accept any interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
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Unless you open a door or the tailgate within
approximately 40 seconds after unlocking
the vehicle:
RThe vehicle will be locked again.
RThe antitheft alarm system will be rearmed.
XGlobal locking: Press lock button : on an
outside door handle.
Selective setting
If you frequently travel alone, you may wish
to reprogram the SmartKey. Grasping the
driver’s outside door handle will then only
unlock the driver’s door and the fuel filler flap.
XSwitching on/off: Press and hold buttons
% and & simultaneously for
approximately 6 seconds until the battery
check lamp (Y page 73) flashes twice.
The SmartKey will then function as follows:
XUnlocking driver’s door and fuel filler
flap: Grasp the driver’s outside door
handle.
XGlobal unlocking: Grasp any outside door
handle other than the driver’s outside door
handle.
XGlobal locking: Press lock button : on an
outside door handle.Checking SmartKey batteries
Example illustration: SmartKey with KEYLESS-GO
XPress button & or % on the
SmartKey.
Battery check lamp : comes on briefly to
indicate that the SmartKey batteries are in
order.
If the battery check lamp does not come on
briefly during check, the SmartKey batteries
are discharged.
XReplace the batteries (Y page 309).
iYou can obtain the required batteries at
any authorized Mercedes-Benz Center.
iIf the batteries are checked within signal
range of the vehicle, pressing button
& or % will lock or unlock the vehicle
accordingly.
Loss of the SmartKey
If you lose your SmartKey or mechanical key,
you should do the following:
XHave the SmartKey deactivated by an
authorized Mercedes-Benz Center.
XReport the loss of the SmartKey or the
mechanical key to your car insurance
company immediately.
XHave the mechanical lock replaced if
necessary.
Any authorized Mercedes-Benz Center will be
glad to supply you with a replacement. For
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information on replacing the SmartKey, see
“Replacing the SmartKey” (Y page 74).
Replacing the SmartKey
Only you, or someone authorized by you can
order a replacement key from any Mercedes-
Benz Center. In order to do so, the Mercedes-
Benz Center will require proof of identity and
vehicle ownership with original documents,
including the following:
If you are the current owner of the vehicle:
Rthe vehicle’s current state registration
Ra current identity card, passport, or drivers
license
If you are an authorized person:
Rthe vehicle’s current state registration
Ra current identity card, passport, or drivers
license for the authorized individual
Rsigned and dated authorization from the
owner of the vehicle for which the key is
being requested
iDuplicated or photocopied
documentation will not be accepted.
Activating the key
Once you, or an authorized person, has
provided the appropriate documents, the
Mercedes-Benz Center will need to
synchronize the key to your vehicle before it
can be used. In order to do so, the Mercedes-
Benz Center need access to your vehicle.
Opening the doors from the inside
You can open a door from the inside even
when it is locked unless it is secured with the
child safety lock (Y page 60).
Open door only when conditions are safe to
do so.
Example illustration driver’s door
If the vehicle has previously been locked with
the SmartKey or with KEYLESS-GO, opening
a door from the inside will trigger the anti-
theft alarm system.
To cancel the alarm, see (Y page 67).
XFront doors: Pull on inside door
handle ; on the respective front door.
If the door was locked, locking knob : will
move up.
XRear doors: Pull up locking knob on the
respective rear door to unlock door.
XPull on the inside door handle on the
respective rear door.
Automatic central locking
The doors and the tailgate lock automatically
when the vehicle is set into motion.
You can open a locked front door from the
inside. Open door only when conditions are
safe to do so.
The doors are designed to unlock
automatically after an accident if the force of
the impact exceeds a preset threshold.
The vehicle locks automatically when the
ignition is switched on and the wheels are
turning at vehicle speeds of above 9 mph
(15 km/h). You could therefore lock yourself
out when the vehicle is pushed or towed or is
on a test stand.
iYou can also activate or deactivate the
automatic central locking using the control
system (Y page 135).
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