
When deployed, the window curtain air bag
offers additional protection for the head.
However, it does not protect your chest or
arms.
In the event of a side impact, the window cur-
tain air bag is deployed on the side on which
the impact occurs.
If the system determines that window curtain air bag deployment can offer additional pro-
tection to that provided by the seat belt, a
window curtain air bag may deploy in other
accident situations (Y page 58).Occupant Classification System
(OCS)
Introduction The Occupant Classification System (OCS)
categorizes the person in the front-passenger
seat. Depending on that result, the front-
passenger front air bag is either enabled or
deactivated.
The system does not deactivate:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
In the following situation, the side impact air
bag and Emergency Tensioning Device are
disabled: the OCS system detects that the
front-passenger seat is occupied, but the seat belt tongue is not inserted in the belt buckle
of the front-passenger seat.
Prerequisites To be classified correctly, the front passenger
must sit:
R with the seat belt fastened correctly
R in an almost upright position with their
back against the seat backrest
R with their feet resting on the floor, if possi-
ble If the front passenger does not observe these
conditions, OCS may produce a false classi-
fication, e.g. because the front passenger:
R transfers their weight by supporting them-
selves on a vehicle armrest
R sits 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 forwards-facing child restraint system must, as far as possible, be resting on
the backrest of the front-passenger seat.
The child restraint system must not touch the roof or be put under strain by the head
restraint. Adjust the angle of the seat back-
rest and the head restraint position accord-
ingly.
Only then can OCS be guaranteed to function correctly. Always observe the child restraint
system manufacturer's installation instruc-
tions.
Occupant Classification System opera-
tion (OCS) PASSENGER AIR BAG OFF indicator lamp
0043
informs you whether the front-passenger
front air bag is deactivated.
X Turn the SmartKey to position 1or 2in the
ignition lock, or press the Start/Stop but- Occupant safety
53Safety Z

You will find further information on stowing
objects, luggage or loads under "Loading
guidelines" (Y page 334). G
WARNING
Child restraint systems or their securing sys-
tems which have been damaged or subjected to a load in an accident can no longer protect
as intended. The child cannot then be
restrained in the event of an accident, heavy
braking or sudden changes of direction. There is an increased risk of injury, possibly even
fatal.
Replace child restraint systems which have
been damaged or subjected to a load in an
accident as soon as possible. Have the secur-
ing systems on the child restraint system
checked at a qualified specialist workshop,
before you install a child restraint system
again.
If it is absolutely necessary to carry a child on the front-passenger seat, be sure to observe
the information on the "Occupant Classifica-
tion System (OCS)" (Y page 53). 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 Stand-
ards 213 and 225
R Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system
corresponds to the standards can be found
on an instruction label on the child restraint
system. This confirmation can also be found
in the installation instructions that are inclu-
ded 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
installation 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 (ISO-
FIX) 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. 0043
LATCH-type (ISOFIX) securing rings
X Install the LATCH-type (ISOFIX) child
restraint system on both LATCH-type (ISO-
FIX) securing rings 0043. Children in the vehicle
63Safety Z

between rear seat backrests
0044and
cargo compartment cover 0043
R when the safety net is installed, Top
Tether belt 0084runs between rear seat
backrests 0044and the safety net.
X Tension Top Tether belt 0084. Make sure you
observe the child restraint system manu-
facturer's installation instructions.
X If necessary, push head restraint 0087back
down slightly (Y page 108). Make sure you
do not interfere with the correct routing of
Top Tether belt 0084. Child restraint system on the front-
passenger seat
General notes Accident statistics show that children
secured in the rear seats are safer than chil-
dren secured in the front-passenger seat. For this reason, Mercedes-Benz strongly advises
that you install a child restraint system on a
rear seat.
If it is absolutely necessary to install a child
restraint system to the front-passenger seat,
be sure to observe the instructions and safety
notes on the "Occupant classification system (OCS)" (Y page 53).
You can thus avoid the risks that could arise
as a result of:
R an incorrectly categorized person in the
front-passenger seat
R the unintentional deactivation of the front-
passenger front air bag
R the unsuitable positioning of the child
restraint system, e.g. too close to the dash-
board
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 (Y
page 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, as far as possible, lie
flat against the backrest of the front-
passenger seat. The child restraint system
must not touch the roof or be put under strain
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 sash guide to the shoulder belt
guide on the child restraint system. The shoul- der belt strap must be routed forwards and
downwards from the vehicle belt sash guide.
If necessary, adjust the vehicle belt sash
guide and the front-passenger seat accord-
ingly.
Always observe the child restraint system
manufacturer's installation and operating
instructions. Children in the vehicle
65Safety Z

Override feature for the rear side win-
dows X
To activate/deactivate: press button0043.
If indicator lamp 0044is 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 0044is off, oper-
ation is possible using the switches in the
rear compartment. Pets in the vehicle
G
WARNING
If you leave animals unattended or unsecured in the vehicle, they could press buttons or
switches, for example.
As a result, they could:
R activate vehicle equipment and become
trapped, for example
R activate 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:
R ABS ( Anti-lock BrakingSystem)
(Y page 68)
R BAS ( Brake Assist System) (Y page 68)
R BAS PLUS ( BrakeAssist System Plus)
(Y page 69)
R COLLISION PREVENTION ASSIST (distance
warning function and adaptive Brake
Assist) (Y page 70)
R ESP ®
(Electronic StabilityProgram)
(Y page 73)
R EBD ( Electronic Brake force Distribution)
(Y page 75)
R ADAPTIVE BRAKE (Y page 75)
R PRE-SAFE ®
Brake (Y page 75)
R STEER CONTROL (Y page 77) Important safety notes
If you fail to adapt your driving style or
become distracted, the driving safety sys-
tems can neither reduce the risk of accident
nor override the laws of physics. Driving
safety systems are merely aids designed to
assist driving. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed and for braking in good time. Always adapt
your driving style to suit the prevailing road
and weather conditions and maintain a safe
distance from the vehicle in front. Drive care-
fully.
i The driving safety systems described only
work as effectively as possible when there
is adequate contact between the tires and
the road surface. Please pay special atten- tion to the notes on tires, recommended
minimum tire tread depths, etc.
(Y page 400).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary, Driving safety systems
67Safety Z

snow chains. Only in this way will the driv-
ing 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 vehi-
cle when braking.
The 0025 ABS warning lamp in the instrument
cluster lights up when the ignition is switched on. It goes out when the engine is running.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 67). G
WARNING
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.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information on the ABS warning lamp (Y page 320) and
display messages which may be shown in the
instrument cluster (Y page 285).
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface condi-
tions. ABS works on slippery surfaces, even
when you only brake gently. Braking X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit- uation is over.
X To make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indica-
tion of hazardous road conditions, and func-
tions as a reminder to take extra care while
driving.
Off-road ABS An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated (Y page 251).
At speeds below 20 mph (30 km/h), the front
wheels lock cyclically during braking. The dig-
ging-in effect achieved in the process reduces the stopping distance on off-road terrain. This
limits steering capability. BAS (Brake Assist System)
General information BAS operates in emergency braking situa-
tions. If you depress the brake pedal quickly,
BAS automatically boosts the braking force,
thus shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 67). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking. 68
Driving safety systemsSafety

Braking
X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. BAS PLUS (Brake Assist System
PLUS)
General information i
Observe the "Important safety notes" sec-
tion (Y page 67).
BAS PLUS is only available in vehicles equip-
ped with DISTRONIC PLUS.
For BAS PLUS to assist you, the radar sensor system must be operational.
With the help of the radar sensor system, BAS
PLUS can detect obstacles that are in the
path of your vehicle for an extended period of time.
If the radar sensor system is malfunctioning,
BAS PLUS will not be available. The brake
system is still available with complete brake
boosting effect and BAS.
BAS PLUS can help you to minimize the risk of
a collision with a vehicle or reduce the effects
of such a collision. If BAS PLUS detects a
danger of collision, you are assisted when
braking.
Important safety notes G
WARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations.
In such cases, BAS PLUS may:
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
BAS PLUS does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
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 dirt on the sensors or anything else cover-
ing the sensors
R there is interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensors checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at low speeds where there is no visible
damage to the front of the vehicle.
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 pressure will be carried out at the last possi-
ble moment. Driving safety systems
69Safety Z

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 traf-
fic 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 40 mph
(70 km/h), BAS PLUS can also react to sta-
tionary objects. Examples of stationary
objects are stopped or parked vehicles.
i If BAS PLUS demands particularly high
braking force, preventative passenger pro-
tection measures (PRE-SAFE ®
) are activa-
ted simultaneously.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
BAS PLUS is deactivated and the brakes func-
tion as usual again, if:
R you release the brake pedal.
R there is no longer a risk of collision.
R no obstacle is detected in front of your
vehicle.
If you have activated DSR (Y page 250), BAS
PLUS is likewise deactivated. COLLISION PREVENTION ASSIST
General notes COLLISION PREVENTION ASSIST consists of
Adaptive Brake Assist and the distance warn-
ing function, which are described in the fol-
lowing.
Distance warning function Important safety notes
i Observe the "Important safety notes" sec-
tion (Y page 67). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and do not rely solely on the distance
warning function.
Function X To activate/deactivate: activate or deac-
tivate the distance warning function in the
on-board computer (Y page 275).
If the distance warning function is not activa-
ted, the 00D4symbol appears in the assis-
tance graphics display.
The distance warning function can help you to minimize the risk of a front-end collision with
a vehicle ahead or reduce the effects of such
a collision. If the distance warning function
detects that there is a risk of a collision, you
will be warned visually and acoustically. The
distance warning function cannot prevent a
collision without your intervention.
Starting at a speed of around 4 mph (7 km/h),
the distance warning function warns you if
you rapidly approach a vehicle in front. An
intermittent warning tone will then sound, 70
Driving safety systemsSafety

Should you approach an obstacle and Adap-
tive Brake Assist has detected a risk of colli-
sion, Adaptive Brake Assist calculates the
braking force necessary to avoid a rear-end
collision. Should you apply the brakes vigo-
rously, Adaptive Brake Assist will automati-
cally increase the braking force to a level suit- able for the traffic conditions.
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
vehicle.
Adaptive Brake Assist is then deactivated.
Vehicles with PRE-SAFE ®
:if adaptive Brake
Assist requires particularly high brake pres-
sure, preventive passenger protection meas-
ures (PRE-SAFE ®
) are deployed simultane-
ously.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
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.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else cover-
ing the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike R
a vehicle traveling in front on a different line
relative to the center of your vehicle
R new vehicles or after the COLLISION PRE-
VENTION ASSIST system has been serv-
iced
Observe the notes in the section on break- ing-in (Y page 156).
Following damage to the front end of the vehi-
cle, have the configuration and operation of
the radar sensor checked at a qualified spe-
cialist workshop. This also applies to colli-
sions at low speeds where there is no visible
damage to the front of the vehicle. ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 67).
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 vehicle 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/4ETS traction control 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 trans-
ferred to the wheel or wheels with traction.
Traction control remains active, even if you
deactivate ESP ®
.
In appropriate driving situations, activate the
off-road program (Y page 251).72
Driving safety systemsSafety