
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.
G WARNING
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 u restraint 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: R
duration R
direction R
intensity
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: R
the ignition is switched on R
the components of the restraint system are
operational. You can find further information
under: "Restraint system warning lamp"
( Y
page 45) R
the 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: R
Front air bags and driver's knee bag R
Window 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 ON indicator lamp is lit.
Observe the information on the PASSENGER AIR
BAG indicator lamps ( Y
page 45).
Your vehicle has two-stage front air bags. During
the first d eployment stage, the front air bag is
fi
lled 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 inOccupant safety 57
Safety Z

the vehicle. This process is pre-emptive in
nature. Deployment should take place in good
time at the start of the collision.
The rate of vehicle deceleration or acceleration
and the direction of the force are essentially
determined by: R
the distribution of forces during the collision R
the collision angle R
the deformation characteristics of the vehicle R
the characteristics of the object with which
the vehicle has collided
Factors which can only be seen and measured
after a collision has occurred do not play a deci-
sive role in the deployment of an air bag. Nor do
they provide an indication of air bag deploy-
ment.
The vehicle can be deformed considerably, with-
out an air bag being deployed. This is the case if
only parts which are relatively easily deformed
are affected and the rate of deceleration is not
high. Conversely, air bags may be deployed even
though the vehicle suffers only minor deforma-
tion. This is the case if, for example, very rigid
vehicle parts such as longitudinal body mem-
bers are hit, and sufficient deceleration occurs
as a result.
If the control unit of the restraint system dete cts
a
side impact or a vehicle rollover, the relevant
components of the restraint system are activa-
ted separately depending on the anticipated
type of accident. R
Side impact air bags on the side where the
impact takes place, independently of the
Emergency Tensioning Device and the use of
the seat belt on the driver's seat and outer
seats in the second row
The side impact air bag on the front-
passenger side (front) deploys under the fol-
lowing conditions: -
the OCS system detects that the front-
passenger seat is occupied or -
the belt tongue is engaged in the belt
buckle of the front-passenger seat R
Window curtain air bag on the side of impact,
independently of the use of the seat belt and
independently of whether the front-
passenger seat is occupied R
Emergency Tensioning Devices, if the system
determines that deployment can offer addi-
tional protection in this situation R
Window curtain air bags on the driver's and
front-passenger side in certain situations when the vehicle rolls over, if the system
determines that deployment can offer addi-
tional protection to that provided by the seat
belt
i Not all air bags are deployed in an accident.
T he different air bag systems work independ-
ently of each other.
How the air bag system works is determined
by the severity of the accident detected,
especially the vehicle deceleration or accel-
eration and the apparent type of accident: R
Frontal collision R
Side impact R
Rollover
PRE-SAFE ®
(anticipatory occupant
protection system)
Introduction In certain hazardous situations, PRE-SAFE ®
takes pre-emptive measures to protect the vehi-
cle occupants.
Important safety notes
! Make sure that there are no objects in the
footwell or behind the seats. There is a danger
that the seats and/or objects could be dam-
aged 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: R
in emergency braking situations, e.g. when
BAS is activated R
in critical driving situations, e.g. when physi-
cal limits are exceeded and the vehicle under-
steers or oversteers severely R
on vehicles with the Driving Assistance pack-
age: if BAS PLUS intervenes powerfully or the
radar sensor system detects an imminent
danger of collision in certain situations58
Occupant safety
Safety

The securing systems of child restraint systems
are: R
the seat belt system R
the LATCH-type (ISOFIX) securing rings R
the Top Tether anchorages
If it is absolutely necessary to carry a child on
the front-passenger seat, be sure to observe the
information on the "Occupant Classification
System (OCS)" ( Y
page 52). There you will also
find information on deactivating the front-
passenger front air bag.
All child restraint systems must meet the fol-
lowing standards: R
U.S. Federal Motor Vehicle Safety Standards
213 and 225 R
Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system cor-
responds to the standards can be found on an
instruction label on the child restraint system.
This confirmation can also be found in the instal-
lation instructions that are included with the
child restraint system.
Observe the warning labels in the vehicle inte-
rior and on the child restraint system.
LATCH-type (ISOFIX) child seat secur-
ing system
G WARNING
LATCH-type (ISOFIX) child restraint systems
do not offer sufficient protective effect for
children whose weight is greater than 48 lbs
(22 kg) who are secured using the safety belt
integrated in the child restraint system. In the
event of an accident, a child might not be
restrained correctly. This poses an increased
risk of injury or even fatal injury.
If the child weighs more than 48 lbs (22 kg),
only use LATCH-type (ISOFIX) child restraint
systems with which the child is also secured
with the vehicle seat belt. Also secure the
child restraint system with the Top Tether
belt, if available.
Always comply with the manufacturer's instal-
lation and operating instructions for the child
restraint system used. Before every trip, make sure that the LATCH-
type (ISOFIX) child restraint system is engaged
correctly in both LATCH-type (ISOFIX) securing
rings
! When installing the child restraint system,
make sure that the seat belt for the middle
seat does not get trapped. The seat belt could
otherwise be damaged.
LATCH-type (ISOFIX) securing rings X
Install the LATCH-type (ISOFIX) child restraint
system on both LATCH-type (ISOFIX) securing
rings C .
ISOFIX is a standardized securing system for
specially designed child restraint systems on
the rear seats. LATCH-type (ISOFIX) securing
rings for two LATCH-type (ISOFIX) child restraint
systems are installed on the left and right of the
rear seats.
Non-LATCH-type (ISOFIX) child seats may also
be used and can be installed using the vehicle's
seat belt system. Install the child seat according
to the manufacturer's instructions.
Top Tether
Introduction Top Tether provides an additional connection
between the child restraint system secured with
a LATCH-type (ISOFIX) system and the vehicle.
This helps reduce the risk of injury even further.
If the child restraint system is equipped with a
Top Tether belt, this should always be used.
Important safety notes
G WARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci-62
Children in the vehicle
Safety

Drivin g safet y systems
Overview of drivin g safet y systemsIn this section , you will fin d information about
th e followin g drivin g safet y systems :R
AB S ( A n ti-loc k B rakin g S ystem)
( Y
page 66)R
BA S ( B rak e A ssist S ystem) ( Y
page 67)R
BA S PLU S wit h Cross-Traffic Assis t ( B r ak e
A ssist S ystem PLU S wit h Cross-Traffic Assist)
( Y
page 67)R
COLLISION PREVENTION ASSIST PLU S
( Y
page 69 )R
ES P ®
( E lectronic S t ability P r ogram)
( Y
page 72)R
EB D ( E lectroni c B rak e forc e D istribution )
( Y
page 74 )R
ADAPTIV E BRAKE ( Y
page 74 )R
PRE-SAF E ®
Brak e ( Y
page 74 )R
STEE R CONTROL ( Y
page 76)
Important safet y notesIf you fail to adapt your drivin g style or if you are
inattentive , th e drivin g safet y systems can nei-
ther reduce th e ris k of an acciden t no r override
th e laws of physics. Driving safet y systems are
merely aids designed to assist driving. You are
responsible fo r maintainin g th e distanc e to th e
vehicle in front, fo r vehicle speed, fo r braking in
goo d time, and fo r stayin g in lane. Always adapt
your drivin g style to suit th e prevailin g road and
weather condition s and maintain a saf e distanc e
from th e vehicle in front. Drive carefully.
The drivin g safet y systems described only wor k
as effectively as possible when there is ade-
quat e contact between th e tires and th e road
surface. Pay particular attention to th e informa-
tion regardin g tires , recommended minimum
tire tread depths etc. in th e "Wheels and tires "
section ( Y
page 387).
In wintr y drivin g conditions, always use winte r
tires (M+ S tires ) and , if necessary, snow chains.
Only in this way will th e drivin g safet y systems
described in this section wor k as effectively as
possible. ABS (Anti-lock Braking System)
General information AB S regulates brake pressure in suc h a way that
th e wheels do no t loc k when you brake . Thi s
allow s you to continue steerin g th e vehicle when
braking .
The % AB S warnin g lamp in th e instrumen t
cluster lights up when th e ignition is switched
on . It goe s out when th e engin e is running .
AB S works from a speed of about 5 mph
(8 km/h), regardles s of road-surfac e conditions.
AB S works on slipper y surfaces, eve n when you
only brake gently.
Important safet y notes
i Observ e th e "Important safet y notes" sec -
tion ( Y
page 66).
G WARNING
If AB S is faulty, th e wheels could loc k when
braking . The steerability and braking charac -
teristics may be severely impaired. Addition -
ally, further drivin g safet y systems are deac -
tivated. There is an increase d danger of skid-
din g and accidents .
Drive on carefully. Hav e AB S checke d imme-
diately at a qualified specialis t workshop .
Whe n AB S is malfunctioning, other systems ,
includin g drivin g safet y systems , will also
becom e inoperative . Observ e th e information
on th e AB S warnin g lamp ( Y
page 319) and dis -
play messages whic h may be shown in th e
instrumen t cluster ( Y
page 281).
Braking X
If ABS intervenes: continue to depress th e
brake peda l vigorousl y until th e braking sit -
uation is over. X
To make a full brak e application: depress
th e brake peda l wit h full force.
If AB S intervenes when braking , you will feel a
pulsin g in th e brake pedal.
The pulsatin g brake peda l can be an indication
of hazardous road conditions, and function s as a
reminder to take extr a car e whil e driving.66
Driving safety systems
Safety

Always pay careful attention to the traffic sit-
uation and be ready to brake. Terminate the
intervention in a non-critical driving situation.
G WARNING
BAS PLUS cannot always clearly identify peo-
ple, this is especially the case if they are mov-
ing. BAS PLUS cannot intervene in these
cases. There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
G WARNING
BAS PLUS does not react: R
to small people, e.g. children R
to animals R
to oncoming vehicles R
when cornering
As a result, BAS PLUS may not intervene in all
critical situations. There is a risk of an acci-
dent.
Always pay careful attention to the traffic sit-
uation and be ready to brake.
In the event of snowfall or heavy rain, the rec-
ognition can be impaired.
Recognition by the radar sensor system is also
impaired in the event of: R
there is dirt on the sensors or anything else
covering the sensors R
there is interference by other radar sources R
there are strong radar reflections, for exam-
ple in parking garages R
a narrow vehicle traveling in front, e.g. a
motorbike R
a vehicle traveling in front on a different line R
vehicles quickly moving into the radar sensor
system detection range
Recognition by the camera system is also
impaired in the event of: R
dirt on the camera or if the camera is covered R
there is glare on the camera system, e.g. from
the sun being low in the sky R
darkness R
if: -
pedestrians move quickly, e.g. into the path
of the vehicle -
the camera system no longer recognizes a
pedestrian as a person due to special cloth-
ing or other objects -
a pedestrian is concealed by other objects -
the typical outline of a person is not distin-
guishable from the background
Following damage to the front end of the vehicle,
have the configuration and operation of the
radar sensors checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the
front of the vehicle.
Following damage to the windshield, have the
configuration and operation of the camera sys-
tem checked at a qualified specialist workshop.
Function To avoid a collision, BAS PLUS calculates the
brake force necessary if: R
you approach an obstacle, and R
BAS PLUS has detected a risk of collision
When driving at a speed under 20 mph
(30 km/h) : if you depress the brake pedal, BAS
PLUS is activated. The increase in brake pres-
sure will be carried out at the last possible
moment.
When driving at a speed above 20 mph
(30 km/h) : if you depress the brake pedal
sharply, BAS PLUS automatically raises the
brake pressure to a value adapted to the traffic
situation.
BAS PLUS provides braking assistance in haz-
ardous situations with vehicles in front within a
speed range between 4 mph (7 km/h) and
155 mph (250 km/h).
At speeds of up to approximately 44 mph
(70 km/h), BAS PLUS can react to: R
stationary objects in the path of your vehicle,
e.g. stopped or parked vehicles R
pedestrians in the path of your vehicle R
objects crossing your path and that are rec-
ognized in the detection range of the sensors
i If BAS PLUS demands particularly high brak-
ing force, preventative passenger protection
measures (PRE-SAFE ®
) are activated simulta-
neously ( Y
page 58).68
Driving safety systems
Safety

been detected as such at least once over the
period of observation.
Up to a speed of approximately 44 mph
(70 km/ h) , Adaptive Brake Assist reacts to sta-
tionary obstacles.
If adaptive Brake Assist demands particularly
high braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activated
simultaneously ( Y
page 58).X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if: R
you release the brake pedal. R
there is no longer any danger of a collision. R
no obstacle is detected in front of your vehi-
cle.
Adaptive Brake Assist is then deactivated.
Important safety notes
i Observe the "Important safety notes" sec-
tion for driving safety systems ( Y
page 66).
G WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can: R
intervene unnecessarily R
not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. Terminate the
intervention in a non-critical driving situation.
G WARNING
Adaptive Brake Assist does not react: R
to people or animals R
to oncoming vehicles R
to crossing traffic R
when cornering
As a result, the Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. Due to the nature of the system, complicated
but non-critical driving situations may also
cause Adaptive Brake Assist to intervene.
If adaptive Brake Assist is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS.
ESP ®
(Electronic Stability Program)
General notes
i Observe the "Important safety notes" sec-
tion ( Y
page 66).
ESP ®
monitors driving stability and traction, i.e.
power transmission between the tires and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilize the vehicle. The
engine output is also modified to keep the vehi-
cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilize
the vehicle during braking.
ETS/4ETS (Electronic Traction System) ETS traction control is part of ESP ®
. On vehicles
with 4MATIC, 4ETS is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.
In appropriate driving situations, activate the
offroad program: X
Vehicles without the Offroad Engineering
package ( Y
page 237) X
Vehicles with the Off-Road Engineering pack-
age ( Y
page 237)Driving safety systems 71
Safety Z

Offroad 4ETS (Electronic Traction Sys-
tem) An ETS system specifically suited to off-road
terrain is activated automatically once an off-
road program is activated: R
Vehicles without the Offroad Engineering
package ( Y
page 237)R
Vehicles with the Off-Road Engineering pack-
age ( Y
page 237)
Important safety notes
G WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilize the vehicle. Additionally, further driv-
ing safety systems are deactivated. This
increases the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
! Vehicles with 4MATIC: only operate the
vehicle for a maximum of ten seconds on a
brake test dynamometer. Switch off the igni-
tion.
Application of the brakes by ESP ®
may oth-
erwise destroy the brake system.
! Vehicles with 4MATIC: function or perform-
ance tests may only be carried out on a 2-axle
dynamometer. Before you operate the vehicle
on such a dynamometer, please consult a
qualified workshop. You could otherwise
damage the drive train or the brake system.
ESP ®
is only deactivated if the

i Activate 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 ®
X
To deactivate: press button C .
The