
can no longer fulfill their protective function
and must be replaced. Visit a qualified spe-
cialist workshop.
XPress the release button in the belt buckle,
hold the belt tongue firmly and guide the belt
back.
Seat belt adjustment
The seat-belt adjustment is an integral part of
the PRE-SAFE®convenience function. This func-
tion adjusts the driver's and front-passenger
seat belt to the upper body of the occupants.
The belt strap is tightened slightly when:
Rthe belt tongue is engaged in the buckle when
the seat-belt extender is retracted and
Rthe ignition is switched on
The seat-belt adjustment will apply a certain
retraction force if any slack is detected between
the vehicle occupant and the seat belt. Do not
hold on to the seat belt tightly while it is adjust- ing.
You can switch the seat-belt adjustment on and
off in the on-board computer (
Ypage 196).
Belt warning for the driver and front
passenger
The 7 seat belt warning lamp in the instru-
ment cluster is a reminder that all vehicle occu-
pants must wear their seat belts. It may light up
continuously or flash. In addition, there may be
a warning tone.
Regardless of whether the driver's seat belt has
already been fastened, the 7seat belt warn-
ing lamp lights up for six seconds each time the
engine is started. If, after six seconds, the driver
or front-passenger seat belt has not been fas-
tened and the doors are closed, the 7seat
belt warning lamp lights up. As soon as the driv- er's and front-passenger seat belts are fastened
or a front door is opened again, the 7seat
belt warning lamp goes out.
If the driver's seat belt is not fastened after the
engine is started, an additional warning tone will
sound. The warning tone switches off after six
seconds or once the driver's seat belt is fas-
tened.
If the vehicle's speed exceeds 15 mph
(25 km/h) once and the driver's and front-
passenger seat belts are not fastened, a warning tone sounds. A warning tone also sounds with increasing intensity for 60 seconds or until the
driver or front passenger have fastened their
seat belts.
If the driver or front passenger unfasten their
seat belts during the journey, the seat belt warn-
ing is activated again.
iMore information on the 7seat belt
warning lamp can be found under "Warning
and indicator lamps in the instrument cluster,
seat belt" (
Ypage 220).
Air bags
Introduction
The air bag installation point is identified by the
label AIR BAG.
An air bag supplements a correctly fastened
seat belt. However, it is not intended as a sub-
stitute for the seat belt. Air bags provide addi-
tional protection in the event of an accident.
Not all air bags are deployed in an accident. The
various air bag systems work independently of
each other (
Ypage 52).
There is, however, no system available today
that can completely rule out injury or death.
It is also not possible to rule out a risk of injury
caused by an air bag due to the high speed at
which the air bag must be deployed.
Important safety notes
GWARNING
If you do not sit in the correct seat position,
the air bag cannot protect as intended and
could even cause additional injury when
deployed. This poses an increased risk of
injury or even fatal injury.
To avoid hazardous situations, always make
sure that all of the vehicle's occupants:
Rhave fastened their seat belts correctly,
including pregnant women
Rare sitting correctly and maintain the great-
est possible distance to the air bags
Rfollow the following instructions
Always make sure that there are no objects
between the air bag and the vehicle's occu-
pants.
Occupant safety45
Safety
Z

Prerequisites
To be classified correctly, the front passenger
must sit:
Rwith the seat belt fastened correctly
Rin an almost upright position with their back
against the seat backrest
Rwith their feet resting on the floor, if possible
If the front passenger does not observe these
conditions, OCS may produce a false classifica-
tion, e.g. because the front passenger:
Rtransfers their weight by supporting them-
selves on a vehicle armrest
Rsits in such a way that their weight is raised
from the seat cushion
If it is absolutely necessary to install a child
restraint system on the front-passenger seat, be
sure to observe the correct positioning of the
child restraint system. Never place objects
under or behind the child restraint system, e.g.
cushions. The entire base of the child restraint
system must always rest on the seat cushion of the front-passenger seat. The backrest of the
forward-facing 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.
Only then can OCS be guaranteed to function
correctly. Always observe the child restraint sys-
tem manufacturer's installation instructions.
Occupant Classification System opera-
tion (OCS)
PASSENGER AIRBAG OFF indicator lamp :
indicates whether the front-passenger front air
bag is disabled.
XTurn the SmartKey to position 1or 2in the
ignition lock, or in vehicles with KEYLESS-GO,
press the start/stop button once or twice.
The system carries out a self-diagnosis test.
The PASSENGER AIR BAG OFF indicator lamp
must light up for about six seconds.
The PASSENGER AIR BAG OFF indicator lamp
then shows the status of the front-passenger
front air bag. If the status of the front-passenger
front air bag changes whilst the vehicle is in
motion, an air bag display message may appear
in the instrument cluster (
Ypage 204). Always
observe the PASSENGER AIR BAG OFF indicator
lamp when the front-passenger seat is occu-
pied. Make sure that the status of the front-
passenger front air bag is correct before and
during a journey.
If the PASSENGER AIRBAG OFF indicator
lamp:
Rlights up, the front-passenger front air bag is
disabled. It will then not be deployed in the
event of an accident.
Rdoes not light up, the front-passenger front
air bag is enabled. If, in the case of an acci-
dent, all deployment criteria are met, the
front-passenger front air bag is deployed.
GWARNING
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the front-passenger front air bag is
disabled. It will not be deployed in the event of
an accident and cannot perform its intended
protective function. A person in the front-
passenger seat could then, for example, come
into contact with the vehicle's interior, espe-
cially if the person is sitting too close to the
dashboard. This poses an increased risk of
injury or even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front- passenger seat is correct and the front-
passenger front air bag is enabled or disa-
Occupant safety49
Safety
Z

bled in accordance with the person in the
front-passenger seat
Rthe front-passenger seat has been moved
back as far back as possible.
Rthe person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct.
GWARNING
If you secure a child in a child restraint system on the front-passenger seat and the
PASSENGER AIR BAG OFF indicator lamp is
off, the front-passenger front air bag can
deploy in the event of an accident. The child
could be struck by the air bag. This poses an
increased risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been disabled. The PASSENGER AIR
BAG OFF indicator lamp must be lit.
GWARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too close to the dashboard, in the event of an
accident, the child could:
Rcome into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
Rbe struck by the air bag if the PASSENGER
AIR BAG OFF indicator lamp is off
This poses an increased risk of injury or even fatal injury.
Move the front-passenger seat as far back as
possible. Always make sure that the shoulder belt strap is correctly routed from the vehicle
seat-belt extender to the shoulder belt guide
on the child restraint system. The shoulder
belt strap must be routed forwards and down-
wards from the retracted vehicle seat-belt
extender. If necessary, adjust the front-
passenger seat accordingly. Always observe
the child restraint system manufacturer's
installation instructions. If OCS detects that:
Rthe front-passenger seat is not occupied, the
PASSENGER AIR BAG OFF indicator lamp
lights up continuously after the system's self-
diagnosis test. This indicates that the front-
passenger front air bag is deactivated.
Rthe front-passenger seat is occupied by a
child aged up to twelve months in a standard
child restraint system, the PASSENGER AIR
BAG OFF indicator lamp lights up continu-
ously after the system's self-diagnosis test.
This indicates that the front-passenger front
air bag is deactivated.
In the case of a twelve-month-old child in a
standard child restraint system, the
PASSENGER AIR BAG OFF indicator lamp may
go out after the system's self-diagnosis test.
This indicates that the front-passenger front
air bag is activated. Categorization is depend- ent on the type of child restraint system and
the stature of the child, for example. In this
case, always in
stall the child restraint system
on a suitable rear seat.
Rthe front-passenger seat is occupied by a per-
son of smaller stature (e.g. a teenager or a
small adult), the PASSENGER AIR BAG OFF
indicator lamp lights up continuously or goes
off after the system's self-diagnosis test
depending on the categorization.
-If the PASSENGER AIR BAG OFF indicator
lamp is off, position the front-passenger
seat as far back as possible. Alternatively, a
person of smaller stature can sit on a rear
seat.
-If the PASSENGER AIR BAG OFF indicator
lamp lights up, a person of smaller stature
should not sit on the front-passenger seat.
Rthe front-passenger seat is occupied by an
adult or a person of an appropriate size, the
PASSENGER AIR BAG OFF indicator lamp
goes out after the system's self-diagnosis
test. This indicates that the front-passenger
front air bag is activated.
If children are traveling in the vehicle, be sure to
observe the notes on "Children in the vehicle"
(
Ypage 56).
If the OCS is malfunctioning, both the red 6
restraint system warning lamp in the instrument
cluster and the PASSENGER AIR BAG OFF indi-
cator lamp light up simultaneously. In this case,
the front-passenger air bag is deactivated and
does not deploy during an accident. Have the
system checked by qualified technicians as
50Occupant safety
Safety

Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 51).
ProblemPossible causes/consequences andMSolutions
The PASSENGER AIR
BAG OFF indicator lamp
lights up and remains lit,
even though the front-
passenger seat is occu-
pied by an adult or a per-
son of a stature corre-
sponding to that of an
adult.The classification of the person on the front-passenger seat is incor-
rect.
XMake sure the conditions for a correct classification of the person
on the front-passenger seat are met (Ypage 49).
XIf the PASSENGER AIR BAG OFF indicator lamp remains lit, the front-
passenger seat may not be used.
XHave OCS checked as soon as possible at an authorized Mercedes- Benz Center.
The PASSENGER AIR
BAG OFF indicator lamp
does not light up and/or
does not stay on.
The front-passenger seat
is:
Runoccupied
Roccupied with the
weight of a child up to
twelve months old in a
child restraint system
OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and the child
seat.
XMake sure that the entire base of the child restraint system rests on
the seat cushion of the front-passenger seat. The backrest of the
forward-facing child restraint system must lie as flat as possible
against the backrest of the front-passenger seat. If necessary,
adjust the position of the front-passenger seat.
XWhen installing the child restraint system, make sure that the seat belt is tight. Do not pull the seat belt tight using the front-passenger
seat adjustment. This could result in the seat belt and the child
restraint system being pulled too tightly.
XCheck for correct installation of the child restraint system.
Make sure that the head restraint does not apply a load to the child
restraint system. If necessary, adjust the head restraint accord-
ingly.
XMake sure that no objects are applying additional weight onto the
seat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains off, do not
install a child restraint system on the front-passenger seat. It is
recommended that you install the child restraint system on a suit-
able rear seat.
XHave OCS checked as soon as possible at an authorized Mercedes-
Benz Center.
Deployment of Emergency Tensioning
Devices and air bags
Important safety notes
GWARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible.
GWARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
52Occupant safety
Safety

Have the vehicle towed to a qualified special-
ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air bags
continue to perform their protective function for
the vehicle occupants in the event of a crash.
GWARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency Ten-
sioning Devices which have been triggered
immediately replaced at a qualified specialist workshop.
An electric motor is used by PRE-SAFE
®to trig-
ger the tightening of the seat belt in hazardous
situations. This procedure is reversible.
If Emergency Tensioning Devices are triggered
or air bags are deployed, you will hear a bang,
and a small amount of powder may also be
released. The 6restraint system warning
lamp lights up.
Only in rare cases will the bang affect your hear-
ing. The powder that is released generally does
not constitute a health hazard, but it may cause
short-term breathing difficulties in people with
asthma or other respiratory problems. Provided
it is safe to do so, you should leave the vehicle
immediately or open the window in order to pre-
vent breathing difficulties.
Air bags and pyrotechnic Emergency Tensioning
Devices (ETDs) 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/HazardousWaste/
Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, the restraint
system control unit evaluates important physi-
cal data relating to vehicle deceleration or accel-
eration, such as:
Rduration
Rdirection
Rintensity
Based on the evaluation of this data, the
restraint system control unit triggers the Emer-
gency Tensioning Devices during a frontal or
rear collision.
An Emergency Tensioning Device can only be
triggered, if:
Rthe ignition is switched on
Rthe components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
(
Ypage 40)
Rthe belt tongue is engaged in the buckle on
the respective front-passenger seat
The Emergency Tensioning Devices in the rear
compartment are triggered independently of the
lock status of the seat belts.
If the restraint system control unit detects a
more severe accident, further components of
the restraint system are activated independ-
ently of each other in certain frontal collision
situations:
RFront air bags and driver's knee bag
RWindow curtain air bag, if the system deter-
mines that deployment can offer additional
protection to that provided by the seat belt
The front-passenger front air bag is activated or
deactivated depending on the person on the
front-passenger seat. The front-passenger front
air bag can only deploy in an accident if the
PASSENGER AIR BAG OFF indicator lamp is off. Observe the information on the PASSENGER AIR
BAG OFF indicator lamp (
Ypage 41).
Your vehicle has two-stage front air bags. During the fi
rst deployment stage, the front air bag is
filled with propellant gas to reduce the risk of
injuries. The front air bag is fully deployed with
the maximum amount of propellant gas if a sec-
ond deployment threshold is reached within a
few milliseconds.
The activation threshold of the Emergency Ten-
sioning Devices and the air bag are determined
by evaluating the rate of vehicle deceleration or
acceleration which occurs at various points in
Occupant safety53
Safety
Z

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.
Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
RABS (Anti-lock BrakingSystem)
(Ypage 62)
RBAS ( Brake Assist System) (Ypage 63)
RBAS PLUS ( BrakeAssist System PLUS) with
Cross-Traffic Assist (Ypage 63)
RCOLLISION PREVENTION ASSIST PLUS
(Ypage 65)
RESP®(Electronic StabilityProgram)
(Ypage 67)
REBD ( Electronic Brake force Distribution)
(Ypage 69)
RADAPTIVE BRAKE (Ypage 69)
RPRE-SAFE®Brake (Ypage 69)
RSTEER CONTROL (Ypage 71)
Important safety notes
If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei- ther reduce the risk of an accident nor override
the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. 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.
The driving safety systems described only work as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Please pay special attention to the
notes on tires, recommended minimum tire
tread depths, etc. (
Ypage 281).
In wintry driving conditions, always use winter
tires (M+S tires) and if necessary, snow chains.
Only in this way will the driving safety systems
described in this section work as effectively as
possible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a way that
the wheels do not lock when you brake. This
allows you to continue steering the vehicle when
braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface conditions.
ABS works on slippery surfaces, even when you
only brake gently.
Important safety notes
iObserve the "Important safety notes" sec-
tion (Ypage 62).
GWARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
62Driving safety systems
Safety

Vehicles without 4MATIC: observe the notes on
ESP®(Ypage 278) when towing the vehicle
with a raised rear axle.
If the å ESP
®OFF warning lamp lights up
continuously, then ESP®is deactivated.
If the ÷ ESP®warning lamp and the å
ESP®OFF warning lamp are lit continuously,
ESP®is not available due to a malfunction.
Observe the information on warning lamps
(
Ypage 222) and display messages which may
be shown in the instrument cluster
(
Ypage 198).
iOnly use wheels with the recommended tire
sizes. Only then will ESP®function properly.
Characteristics of ESP®
General information
If the ÷ ESP warning lamp goes out before
beginning the journey, ESP®is automatically
active.
If ESP
®intervenes, the ÷ESP®warning lamp
flashes in the instrument cluster.
If ESP
®intervenes:
XDo not deactivate ESP®under any circum-
stances.
XOnly depress the accelerator pedal as far as
necessary when pulling away.
XAdapt your driving style to suit the prevailing
road and weather conditions.
ECO start/stop function
The ECO start/stop function switches the
engine off automatically when the vehicle stops
moving. The engine starts automatically when
the driver wants to pull away again. ESP
®
remains in its previously selected status. Exam-
ple: if ESP®was deactivated before the engine
was switched off, ESP®remains deactivated
when the engine is switched on again.
Deactivating/activating ESP®
Important safety notes
You can select between the following states of
ESP®:
RESP®is activated.
RESP®is deactivated.
GWARNING
If you deactivate ESP
®, ESP®no longer sta-
bilizes the vehicle. There is an increased risk
of skidding and an accident.
Only deactivate ESP
®in the situations descri-
bed in the following.
It may be best to deactivate ESP
®in the follow-
ing situations:
Rwhen using snow chains
Rin deep snow
Ron sand or gravel
iActivate ESP®as soon as the situations
described above no longer apply. ESP®will
otherwise not be able to stabilize the vehicle if
the vehicle starts to skid or a wheel starts to
spin.
!Avoid spinning the driven wheels for an
extended period with ESP®deactivated. You
could otherwise damage the drivetrain.
Deactivating/activating ESP®
You can deactivate or activate ESP®via the on-
board computer (Ypage 191).
ESP®deactivated:
The å ESP®OFF warning lamp in the instru-
ment cluster lights up.
ESP
®activated:
The å ESP®OFF warning lamp in the instru-
ment cluster goes out.
Characteristics when ESP®is deactivated
If ESP®is deactivated and one or more wheels
start to spin, the ÷ESP®warning lamp in the
instrument cluster flashes. In such situations,
ESP
®will not stabilize the vehicle.
If you deactivate ESP®:
RESP®no longer improves driving stability.
REngine torque is no longer limited and the
drive wheels are able to spin.
The spinning of the wheels results in a cutting
action for better traction on loose surfaces.
RTraction control is still activated.
RCOLLISION PREVENTION ASSIST is no longer
available; nor is it activated if you brake firmly
with assistance from ESP
®.
68Driving safety systems
Safety

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.
When locking or unlocking with KEYLESS-GO,
the distance between the SmartKey and the cor-
responding 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 the external door handles are touched
Rwhen starting the engine
Rwhile the vehicle is in motion
XTo unlock the vehicle: touch the inner sur-
face of the door handle.
XTo lock the vehicle: touch sensor sur-
face :.
XConvenience closing feature: touch
recessed sensor surface ;for an extended
period.
Further information on the convenience clos-
ing feature (
Ypage 84).
XTo unlock the trunk lid: pull the handle on
the trunk lid.
The vehicle only unlocks the trunk lid.
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.
XTo deactivate: press the&button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
(
Ypage 76) flashes twice briefly and lights
up once, then KEYLESS-GO is deactivated.
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.
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
alone.
XTo change the setting: simultaneously press
the % and& buttons on the SmartKey
for approximately six seconds until the bat-
tery check lamp flashes twice (
Ypage 76).
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 centrally: press the&button.
74SmartKey
Opening and closing