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doors must therefore only be performed by
qualified technicians. Contact an authorized
Mercedes-Benz Center.
GWarning!
Only use seat covers which have been tested
and approved by Mercedes-Benz for your
vehicle model. Using other seat covers may
interfere with or prevent the deployment of
the side impact air bags. Contact an
authorized Mercedes-Benz Center for
availability.
When deployed, the side impact air bags offer
additional protection for the thorax of the
vehicle occupants on the side of the vehicle
on which the impact occurs. However, they
do not protect the:
Rhead
Rneck
Rarms
Front side impact air bags : and rear side
impact air bags ; are deployed next to the
outer seat cushions.
The side impact air bags are deployed:
Ron the side on which an impact occurs
Rat the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
Rindependently of seat belt use
Rindependently of the front air bags
Rindependently of the belt tensioners
If the vehicle overturns, the side impact air
bags are generally not deployed. They are
deployed if the system detects high vehicle
deceleration or acceleration in a lateral
direction and determines that side impact air
bag deployment can offer additional
protection to that provided by the seat belt.
The side impact air bags will not deploy in side
impacts with deceleration rates which do not
exceed the system’s preset deployment
thresholds for vehicle deceleration or
acceleration. You will then be protected by
the seat belt.
If the OCS detects that the front-passenger
seat is not occupied and the front-passenger
seat belt is not fastened (the belt tongue is
not engaged in the seat belt buckle), the side
impact air bag on the front-passenger side
will not deploy. The side impact air bag on the
front-passenger side will deploy if the front-
passenger seat belt is fastened, regardless of
whether the front-passenger seat is occupied
or not.
Window curtain air bags
GWarning
Observe "Important safety notes"
(Y page 44).
The window curtain air bags enhance the level
of protection for the head (but not chest or
arms) of the vehicle occupants on the side of
the vehicle on which the impact occurs.
The window curtain air bags are integrated
into the side of the roof frame and deploy in
the area extending from the front door (A-
pillar) to the rear door (C-pillar).
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Window curtain air bags : are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R regardless of whether the front-passenger
seat is occupied
R independently of seat belt use
R if the vehicle overturns and the system
determines that window curtain air bag
deployment can offer additional protection
to that provided by the seat belt
R independently of the front air bags
Window curtain air bags : will not deploy in
impacts with deceleration rates which do not
exceed the system’s preset deployment
thresholds for vehicle deceleration or
acceleration. You will then be protected by
the seat belt.
Occupant classification system (OCS)
Operating principles of the Occupant
Classification System
OCS categorizes the occupant on the front-
passenger seat by means of a weight sensor.
The front-passenger front air bag is
automatically deactivated for certain weight
categories. The respective status can be
recognized by the 42 indicator
lamp. With the 42 indicator
lamp illuminated, the front-passenger front
air bag is deactivated.
The system does not deactivate:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
To be classified correctly, the front passenger
must sit:
R with the seat belt properly fastened
R in a position that is as upright as possible
with the back against the seat backrest
R with their feet on the floor
If the front-passenger's weight is transferred
to another object in the vehicle (e.g. by
leaning on armrests), OCS may not be able to
approximate the occupant's weight category.
If the front passenger seat, the seat cover, or
the seat cushion are damaged, have the
necessary repair work carried out at an
authorized Mercedes-Benz Center.
For reasons of safety, Mercedes-Benz
recommends that you only use seat
accessories that have been approved by
Mercedes-Benz.
Both the driver and the front passenger
should observe the 42 indicator
lamp to determine whether or not the front
passenger is positioned correctly.GWarning
If the 42 indicator lamp lights up
when an adult or someone larger than a small
individual is in the front-passenger seat, have
the front passenger reposition himself or
herself in the seat until the 42
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag deployment when the OCS has classified
the front-passenger seat occupant as
weighing as much as or less than a typical 12-
month-old child in a standard child restraint
or if the front-passenger seat is classified as
being empty.
When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, the 42 indicator lamp
will illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
the 42 indicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
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When the OCS senses that the front-
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated in a standard child
restraint or as being a small individual (such
as a young teenager or a small adult), the
42 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then, depending on occupant
weight sensor readings from the front-
passenger seat, remain illuminated or go out.
With the 42 indicator lamp
illuminated, the front-passenger front air bag
is deactivated. With the 42
indicator lamp out, the front-passenger front
air bag is activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adult or someone larger than a small
individual, the 42 indicator lamp
will illuminate for approximately 6 seconds
when the engine is started and then go out,
indicating that the front-passenger front air
bag is activated.
If the 42 indicator lamp is
illuminated, the front-passenger front air bag
is deactivated and will not be deployed.
If the 42 indicator lamp is not
illuminated, the front-passenger front air bag
is activated and will be deployed:
R in the event of certain frontal impacts
R if impact exceeds a preset deployment
threshold
R independently of the side impact air bags
If the front-passenger front air bag is
deployed, the rate of inflation will be
influenced by:
R the rate of vehicle deceleration as assessed
by the air bag control unit
R the front passenger's weight category as
identified by OCS
For further information, see the section
regarding air bag display messages
( Y page 386).GWarning
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. Thus,
we strongly recommend that children be
placed in the rear seats whenever possible.
Regardless of seating position, children 12
years old and under must be seated and
properly secured in an appropriately sized
child restraint system or booster seat
recommended for the size and weight of the
child.
The infant or child restraint system must be
properly secured with the vehicle's seat belt,
the seat belt and Top Tether strap, or lower
anchors and Top Tether strap, fully in
accordance with the child seat
manufacturer's instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriate sized infant
restraint, toddler restraint, or booster seat
recommended for the size and weight of the
child.
Children can be killed or seriously injured by
an inflating air bag. Note the following
important information when circumstances
require you to place a child in the front-
passenger seat:
R Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the front-passenger seat.
R A child in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
Occupant safety49SafetyZ
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recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
RIf you install a rear-facing child restraint on
the front-passenger seat, make sure the
42 indicator lamp is
illuminated, indicating that the front-
passenger front air bag is deactivated.
Should the 42 indicator lamp
not illuminate or go out while the restraint
is installed, please check installation.
Periodically check the 42
indicator lamp while driving to make sure
the 42 indicator lamp is
illuminated. If the 42 indicator
lamp goes out or remains out, do not
transport a child on the front-passenger
seat until the system has been repaired.
A child in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates.
RIf you place a child in a forward-facing child
restraint on the front-passenger seat:
-move the seat as far back as possible
-use the proper child restraint
recommended for the age, size and
weight of the child
-secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
RFor children larger than a typical 12-month-
old child, the front-passenger front air bag
can be activated or deactivated.
Deployment of the driver front air bag does
not mean that the front-passenger front air
bag should also have deployed.
OCS may have determined:
Rthat the seat was unoccupied or occupied
by a weight of up to or less than that of a
typical 12-month-old child seated in a
standard child restraint
Rthat the seat was occupied by a small
individual (e.g. a young teenager or a small
adult) or a child who weighs more than a
typical 12-month-old child in a standard
child restraint system
These are examples of when OCS deactivates
the front-passenger front air bag. The air bag
is deactivated despite the impact fulfilling the
criteria for deploying the driver's front air bag.
If the SmartKey has been removed from the
ignition lock or is in position 0, indicator lamp
42: does not light up.
GWarning
If the red SRS 6 indicator lamp in the
instrument cluster and the 42
indicator lamp are lit at the same time, there
is a malfunction in the OCS. The front
passenger front air bag will be deactivated in
this case. Have the system checked by
qualified technicians as soon as possible.
Contact an authorized Mercedes-Benz
Center.
Only have the seat repaired or replaced at an
authorized Mercedes-Benz Center.
In order to ensure proper operation of the air
bag system and OCS:
RSit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
RWhen seated, a passenger should not
position him/herself in such a way as to
cause the passenger's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
50Occupant safetySafety
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approximate the passenger's weight
category.
R Read and observe all warnings in this
chapter.
System self-test
The 42 indicator lamp
illuminates when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R press the KEYLESS-GO Start/Stop button
once or twice
If an adult occupant is properly sitting on the
passenger seat and the OCS classifies the
occupant as an adult, the 42
indicator lamp illuminates and goes out again
after approximately 6 seconds.
If the seat is not occupied and the OCS
classifies the front passenger seat as being
unoccupied, the 4 indicator
lamp 2 will illuminate and not go out.
GWarning!
If the 4 2 indicator lamp does
not illuminate, the system is not functioning.
You must contact an authorized Mercedes-
Benz Center before seating any child on the
front passenger seat.
For more information, see "Problems with the
Occupant Classification System"
( Y page 52).
GWarning
Never place anything between seat cushion
and child seat (e.g. a pillow), since it reduces
the effectiveness of the OCS. The underside
and rear side child restraint system must be
placed entirely on the seat cushion and the
backrest of the front-passenger seat
backrest.
If necessary, adjust the tilt of the passenger
seat backrest.
An incorrectly mounted child seat could cause
injuries to the child in case of an accident,
instead of increasing protection for the child.
Follow the manufacturer's instructions for
installation of child restraint systems.Occupant safety51SafetyZ
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Problems with the occupant classification systemProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp
illuminates and
remains illuminated.
The person sitting on
the front-passenger
seat:
R weighs as much as a
typical adult
R weighs more than a
childOCS is malfunctioning.XHave OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XObserve the additional display messages in the multifunction
display ( Y page 386).GWarning
If the 42 indicator lamp illuminates and remains illuminated when the weight of a
typical adult or someone larger than a small individual has been detected on the passenger seat,
the system then determines the occupant cannot be a child. Do not allow any occupant to use
the passenger seat until the system has been repaired.
ProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp does not
illuminate and/or does
not remain illuminated.
The front-passenger
seat is:
R unoccupied
R occupied with the
weight of a typical
12-month-old child in
a standard child
restraint or lessOCS is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XMake sure there are no objects applying additional weight onto
the seat.XIf the 42 indicator lamp does not illuminate, have
OCS checked as soon as possible at an authorized Mercedes-
Benz Center. Do not transport a child on the front-passenger
seat until OCS has been repaired.XObserve the additional display messages in the multifunction
display ( Y page 386).GWarning
If the 42 indicator lamp does not illuminate or remains out with the weight of a
typical 12-month-old child in a standard child restraint or less, or is unoccupied, on the front-
passenger seat, do not transport a child on the front-passenger seat until the system has been
repaired.
52Occupant safetySafety
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PRE-SAFE®
systemGWarning
The PRE-SAFE ®
system reduces the impact of
an accident on vehicle occupants, as long as
their seat belts have been fastened correctly.
Although your vehicle is equipped with a PRE-
SAFE ®
system, the possibility of injury in the
event of an accident cannot be ruled out. You
should therefore always drive carefully and
adapt your driving style to the prevailing road,
weather and traffic conditions.
PRE-SAFE ®
takes pre-emptive measures to
protect occupants in certain hazardous
situations.
PRE-SAFE ®
intervenes:
R in emergency braking situations, e.g. if BAS
is activated or, in vehicles with DISTRONIC
PLUS, where BAS PLUS intervenes
powerfully
R if, on vehicles with DISTRONIC PLUS, the
radar sensor system detects an imminent
danger of collision in certain situations
R in critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely
or when having to swerve to avoid an
obstacle at a speed
PRE-SAFE ®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R the front-passenger seat or the electrically
adjustable outer rear seats are adjusted if
they are in unfavorable position.
R on vehicles with a multicontour seat or an
active multicontour seat: the air pressure
in the side bolsters on the seat cushion and
the side bolsters on the backrest is
increased.
R on vehicles with multicontour seats in the
rear: the air pressure in the backrest side
bolsters of the outer seats in the rear is
increased.
R if the vehicle skids, the sliding sunroof,
panorama sliding sunroof and the side
windows are closed so that only a small gap
remains.
If the sliding sunroof, panorama roof with
power tilt/sliding panel or a side window is
obstructed when closing, the closing
procedure is stopped. The obstructed sliding
sunroof, panorama roof with power tilt/
sliding panel or side window then opens again
slightly.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. The air pressure in the
side bolsters on the multicontour seat/active
multicontour seat is reduced again. All
settings made by PRE-SAFE ®
can then be
reversed.
If the seat belts are not released:XMove the backrest back slightly, but only
when the vehicle is stationary.
The belt pretensioning is reduced and the
locking mechanism is released.GWarning
Make sure that nobody can become trapped
as you adjust the seat.
! Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
More information about seat-belt
adjustment, a convenience function
integrated into PRE-SAFE ®
, can be found in
the "Seat-belt adjustment" section
( Y page 58).
NECK-PRO head restraints/NECK-
PRO luxury head restraints
NECK-PRO head restraints/NECK-PRO luxury
head restraints increase protection of the
driver’s and front-passenger’s head and neck.
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In the event of a rear collision of a certain
severity, the NECK-PRO head restraints/
NECK-PRO luxury head restraints on the
driver's and the front-passenger seat are
moved forwards and upwards. This provides
better head support.
GWarning
Do not attach any objects (e.g. a coat hanger)
to the NECK-PRO head restraints/NECK-PRO
luxury head restraints. Otherwise, the NECK-
PRO head restraints/NECK-PRO luxury head
restraints may not function properly and in
the event of a rear-end collision may not offer
the protection they are designed to provide.
GWarning
Only use seat covers/head restraint covers
that have been tested and approved by
Mercedes-Benz for your vehicle model.
Using seat covers and head restraint covers
other than those recommended may cause a
malfunction when NECK-PRO head
restraints/NECK-PRO luxury head restraints
are triggered or may prevent side impact air
bags/pelvis air bags from deploying.
Consult an authorized Mercedes-Benz Center
regarding availability.
If the NECK-PRO head restraints/NECK-PRO
luxury head restraints have been triggered in
an accident, reset the NECK-PRO head
restraints/NECK-PRO luxury head restraints
on the driver's and front-passenger seats
(Y page 54). Otherwise, the additional
protection will not be available in the event of
another rear-end collision. NECK-PRO head
restraints/NECK-PRO luxury head restraints
that have been triggered are moved forwards
and can no longer be adjusted.
GWarning!
For your protection, drive only with properly
positioned head restraints.
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. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation.
Resetting triggered NECK-PRO head
restraints
Important safety notes
GWarning
For reasons of safety, have the NECK-PRO
head restraints/NECK-PRO luxury head
restraints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
GWarning
When pushing back the NECK-PRO head
restraint cushion, make sure your fingers do
not become caught between the head
restraint cushion and the cover. Failure to
observe this could result in injuries.
NECK-PRO head restraints
iResetting the NECK-PRO head restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
54Occupant safetySafety