
How the air bag system works is deter-
mined by the severity of the accident detec-
ted, especially the vehicle deceleration or
acceleration and the apparent type of acci-
dent:
Rfrontal collision
Rside impact
Rrollover
PRE-SAFE®(anticipatory occupant
protection system)
Introduction
In certain hazardous situations, PRE-SAFE®
takes pre-emptive measures to protect the
vehicle occupants.
Important safety notes
!Make sure that there are no objects in the
footwell or behind the seats. There is a dan-
ger that the seats and/or objects could be
damaged when PRE-SAFE
®is activated.
Although your vehicle is equipped with PRE-
SAFE
®, the possibility of injury in the event of
an accident cannot be ruled out. Always
adapt your driving style to suit the prevailing
road and weather conditions and maintain a
safe distance from the vehicle in front. Drive
carefully.
Function
PRE-SAFE®intervenes:
Rin emergency braking situations, e.g. when
BAS is activated
Rin critical driving situations, e.g. when phys-
ical limits are exceeded and the vehicle
understeers or oversteers severely
Ron vehicles with the Driving Assistance
package: if BAS PLUS intervenes power-
fully or the radar sensor system detects an
imminent danger of collision in certain sit-
uations PRE-SAFE
®takes the following measures
depending on the hazardous situation detec-
ted:
Rthe front seat belts are pre-tensioned.
Rif the vehicle skids, the sliding sunroof and
the side windows are closed so that only a
small gap remains. The panorama roof with
power tilt/sliding panel is completely
closed.
Rvehicles with the memory function: the
front-passenger seat is adjusted if it is in an
unfavorable position.
Rvehicles with a multicontour seat: the air
pressure in the side bolsters of the seat
backrest is increased.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE
®slackens
the belt pre-tensioning. On vehicles with mul-
ticontour seats, the air pressure in the side
bolsters is reduced again. All settings made
by PRE-SAFE
®can then be reversed.
If the seat belt pre-tensioning is not reduced:
XMove the seat backrest or seat back
slightly when the vehicle is stationary.
The seat belt pre-tensioning is reduced and the locking mechanism is released.
The seat-belt adjustment is an integral part of
the PR
E-SAFE®convenience function. You
will find information on the convenience func-
tion under "Belt adjustment" (
Ypage 49).
Automatic measures after an acci-
dent
Immediately after an accident, the following
measures are implemented, depending on
the type and severity of the impact:
Rthe hazard warning lamps are activated
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rvehicles with a memory function: the elec-
trically adjustable steering wheel is raised
60Occupant safety
Safety

Rearward-facing child restraint system
If it is absolutely necessary to install a rear-
ward-facing child restraint system on the
front-passenger seat, always make sure that
the front-passenger front air bag is deactiva-
ted. Only if the PASSENGER AIR BAG OFF
indicator lamp is permanently lit (
Ypage 45)
is the front-passenger front air bag deactiva-
ted.
Always observe the child restraint system
manufacturer's installation and operating
instructions.
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 shoul- der 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 forwards and down-
wards from the vehicle belt outlet. If neces-
sary, adjust the vehicle belt outlet and the
front-passenger seat accordingly.
Always observe the child restraint system
manufacturer's installation and operating
instructions.
Child-proof locks
Important safety notes
GWARNING
If children are traveling in the vehicle, they
could:
Ropen doors, thus endangering other people
or road users
Rexit the vehicle and be caught by oncoming
traffic
Roperate 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:
Rthe rear doors (Ypage 67)
Rthe rear side windows (Ypage 67)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart 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.
GWARNING
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.
66Children in the vehicle
Safety

GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro- tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Child-proof locks for the rear doors
You secure each door individually with the
child-proof locks on the rear doors. A door
secured with a child-proof lock cannot be
opened from inside the vehicle. When the
vehicle is unlocked, the door can be opened
from the outside.
XTo activate: press the child-proof lock
lever up in the direction of arrow :.
XMake sure that the child-proof locks are
working properly.
XTo deactivate:press the child-proof lock
lever down in the direction of arrow ;.
Override feature for the rear side win-
dows
XTo activate/deactivate:press button:.
If indicator lamp ;is lit, operation of the
rear side windows is disabled. Operation is
only possible using the switches in the driv-
er's door. If indicator lamp ;is off, oper-
ation is possible using the switches in the
rear compartment.
Pets in the vehicle
GWARNING
If you leave animals unattended or unsecured
in the vehicle, they could press buttons or
switches, for example.
As a result, they could:
Ractivate vehicle equipment and become
trapped, for example
Ractivate or deactivate systems, thereby
endangering other road users
Unsecured animals could also be flung around
the vehicle in the event of an accident or sud-
den steering or braking, thereby injuring vehi-
cle occupants. There is a risk of an accident
and injury.
Never leave animals unattended in the vehi-
cle. Always secure animals properly during
the journey, e.g. use a suitable animal trans-
port box.
Pets in the vehicle67
Safety
Z

Power steering will, however, continue to
function.
Protection against theft
Immobilizer
XTo activate with the SmartKey:remove
the SmartKey from the ignition lock.
XTo activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
XTo 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. Any-
one 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 star-
ted (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).
ATA (anti-theft alarm system)
XTo arm: lock the vehicle with the SmartKey
or KEYLESS-GO.
Indicator lamp :flashes. The alarm sys-
tem is armed after approximately
15 seconds.
XTo deactivate using the SmartKey:
unlock the vehicle with the SmartKey.
or
XInsert the SmartKey into the ignition lock.
XTo deactivate using KEYLESS-GO: unlock
the vehicle with KEYLESS-GO.
or
XPress the Start/Stop button on the dash-
board. The SmartKey must be inside the
vehicle.
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
SmartKey.
The alarm is switched off.
or
XInsert the SmartKey into the ignition lock.
The alarm is switched off.
XTo stop the alarm using KEYLESS-GO:
grasp the outside door handle. The Smart-
Key must be outside the vehicle.
The alarm is switched off.
or
XPress the Start/Stop button on the dash-
board. The SmartKey must be inside the
vehicle.
The alarm is switched off.
The alarm is not switched off, even if you
close the open door that triggered it, for
example.
78Protection against theft
Safety

Useful information
i
This Operator's Manual describes all
models and all standard and optional equip-
ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
iRead the information on qualified special-
ist workshops (
Ypage 29).
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 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.
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
magnetic fields. Otherwise, the remote
control function could be affected.
Strong magnetic fields can occur in the
vicinity of powerful electrical installations.
Do not store 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
SmartKey.
Do not keep the KEYLESS-GO key in the tem-
perature-controlled cup holder. Otherwise,
the KEYLESS-GO key will not be recognized.
SmartKey functions
:& Locks the vehicle
;FOpens/closes the tailgate
=%Unlocks the vehicle
XTo unlock centrally: press the=button.
82SmartKey
Opening and closing

If you do not open the vehicle within
approximately 40 seconds of unlocking:
Rthe vehicle is locked again.
Rprotection against theft is reactivated.
XTo lock centrally:press button:.
The SmartKey centrally locks and unlocks the following components:
Rthe doors
Rthe tailgate
Rthe 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 (
Ypage 285).
You will receive visual and acoustic locking
confirmation if all components were able to
be locked.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (
Ypage 284).
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.
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 functions of KEYLESS-GO with those of a con-
ventional SmartKey. Unlock the vehicle by
using KEYLESS-GO, for instance, and lock it
using the &button on the SmartKey.
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 Smart-
Key is in the vehicle by periodically establish-
ing a radio connection between the vehicle
and the SmartKey. This happens:
Rwhen the external door handles are
touched
Rwhen starting the engine
Rwhile the vehicle is in motion
XTo unlock the vehicle:
touch the inner
surface of the door handle.
XTo lock the vehicle: touch sensor sur-
face :.
XConvenience closing feature: touch
recessed sensor surface ;for an exten-
ded period.
Further information on the convenience clos-
ing feature (
Ypage 99).
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 key for an exten-
ded 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.
SmartKey83
Opening and closing
Z

XTo deactivate:press the&button on
the SmartKey twice in rapid succession.
The battery check lamp (
Ypage 85) of the
SmartKey flashes twice briefly and lights up
once, then KEYLESS-GO is deactivated.
XTo activate: press any button on the
SmartKey or insert the SmartKey into the
ignition lock.
KEYLESS-GO and all of its associated fea-
tures 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
SmartKey in the vehicle.
Changing the settings of the locking
system
You can change the settings of the locking
system. 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 fre-
quently travel on your own.
XTo change the setting: press and hold
down the %and& buttons simulta-
neously for approximately six seconds until
the battery check lamp flashes twice
(
Ypage 85).
iIf the setting of the locking system is
changed within the signal range of the vehi-
cle, pressing the &or% button:
Rlocks or
Runlocks the vehicle
The SmartKey now functions as follows:
XTo unlock the driver's door: press the
% button once.
XTo unlock centrally: press the%but-
ton twice.
XTo lock centrally: press the&button. The KEYLESS-GO function is changed as fol-
lows:
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 sur-
face of the door handle on the front-
passenger door or the rear door.
XTo lock centrally: touch the outer sensor
surface on one of the door handles
(
Ypage 83).
XTo restore the factory settings: press
and hold d
own the %and& buttons
simultaneously for approximately six sec-
onds until the battery check lamp flashes
twice (
Ypage 85).
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 (
Ypage 78).
There are several ways to turn off the alarm:
XTo turn the alarm off with the SmartKey:
press the %or& button on the
SmartKey.
or
XInsert the SmartKey into the ignition lock.
or
XTo deactivate the alarm with KEYLESS-
GO: press the Start/Stop button in the igni-
tion lock. The SmartKey must be in the
vehicle.
or
XLock or unlock the vehicle using KEYLESS-
GO. The SmartKey must be outside the
vehicle.
84SmartKey
Opening and closing

If you unlock the vehicle using the mechanical
key, the fuel filler flap will not be unlocked
automatically.
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
mechanical key ;from the SmartKey.
For further information about:
Runlocking the driver's door (Ypage 92)
Runlocking the cargo compartment
(
Ypage 97)
Rlocking the vehicle (Ypage 92)
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.
Mercedes-Benz recommends that you have
the batteries replaced at a qualified specialist
workshop.
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/Hazard-
ousWaste/Perchlorate/index.cfm.
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 85).
iIf 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 Smart-
Key (
Ypage 84).
SmartKey85
Opening and closing
Z