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increase the risk and potential severity of
hand/arm injury when the driver front air
bag inflates.
R Adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R Occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates. This could result in
serious injuries or death should the side
impact air bag be deployed. Always sit as
upright as possible, wear the seat belt
properly and use an appropriately sized
child restraint, infant restraint or booster
seat recommended for the size and weight
of the child.
R Canada only: children under 12 years may
only sit in the front-passenger seat if they
are seated in a child restraint system which
is compatible with BabySmart™ and
approved by Mercedes-Benz. If the child
restraint system is installed properly, the
front-passenger front air bag is deactivated
in conjunction with the BabySmart™
system installed in the vehicle. Otherwise,
the child could be struck by the air bag
when it inflates in a crash. This could lead
to serious or fatal injuries.
Failure to follow these instructions can result
in severe injuries to you or other occupants.
If you sell your vehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual.GWarning
Accident research shows that the safest place
for children in an automobile is in a rear seat.
A side impact air bag related injury may occur
if occupants, especially children, are not
properly seated or restrained when next to a
side impact air bag which needs to deploy
rapidly in a side impact in order to do its job.
To help avoid the possibility of injury, please
follow these guidelines:(1)Always sit as upright as possible
and use the seat belts properly.
Make sure that children 12 years
old and under use an appropriately
sized child restraint, infant
restraint, or booster seat
recommended for the size and
weight of the child.(2)Always wear seat belts properly.
The air bags are only deployed if the air bag
control unit detects the need for deployment.
Only in the event of such a situation will they
provide their supplemental protection.
The driver and passenger should always wear
their seat belts. Otherwise, it is not possible
for the air bags to provide their supplemental
protection.
In the event of other types of impacts and
impacts below air bag deployment
thresholds, air bags will not deploy. The driver
and passengers will then be protected to the
extent possible by a properly fastened seat
belt. A properly fastened seat belt is also
needed to provide the best possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
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.
Front air bags
GWarning
Observe "Important safety instructions"
( Y page 38).
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The front air bags increase protection for the
driver's and front passenger's head and
chest.
Driver's air bag : deploys in front of the
steering wheel; front-passenger air bag ;
deploys in front of and above the glove box.
They are deployed:
R in the event of certain frontal impacts
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R if the seat belt is fastened
R independently of other air bags in the
vehicle
If the vehicle overturns, the front air bags are
generally not deployed unless the system
detects high vehicle deceleration in a
longitudinal direction.
Your vehicle has adaptive, dual-stage front air
bags. In the event of a collision, the air bag
control unit evaluates the vehicle
deceleration. When the first deployment
threshold is reached, the front air bag is filled
with enough propellant gas to reduce the risk
of injuries. The front air bag is fully deployed
if a second deployment threshold is exceeded
within a few milliseconds.
Vehicles with OCS (USA only): front-
passenger front air bag deployment is also
influenced by the passenger's weight
category as identified by the Occupant
Classification System (OCS) ( Y page 42).
Vehicles with OCS (USA only): the lighter the
passenger side occupant, the higher the
vehicle deceleration rate required for second
stage inflation of the front-passenger front air
bag. In the second stage, the front air bags
are inflated with the maximum amount of
propellant gas available.
The air bags will not deploy in impacts which
do not exceed the system's preset
deployment thresholds. You will then be
protected by the seat belt.
! Vehicles with BabySmart™ (Canada only):
do not place objects heavier than 20 lb
(9 kg) on the front-passenger seat, as this
could be interpreted as the seat being
occupied. In the event of an accident, the
restraint systems on the front-passenger
side are deployed. Have restraint systems
replaced that have been deployed.
The front-passenger front air bag will only
deploy if:
R the system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied (USA only).
R the 42 indicator lamp in the
center console is not lit, USA:
( Y page 42), Canada: ( Y page 48).
R the impact exceeds a preset deployment
threshold
Side impact air bagsGWarning
Observe "Important safety instructions"
( Y page 38).
GWarning!
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition of components to the
doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
40Occupant safetySafety
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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:
R head
R neck
R arms
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:
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 independently of seat belt use
R independently of the front air bags
R independently of the ETDs
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 are not deployed in
side impacts which do not exceed the
system's deployment threshold.
Vehicles with OCS (USA only): if 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.
! Vehicles with BabySmart™ (Canada only):
do not place objects heavier than 20 lb
(9 kg) on the front-passenger seat, as this
could be interpreted as the seat being
occupied. In the event of an accident, the
restraint systems on the front-passenger
side are deployed. Have restraint systems
replaced that have been deployed.
Window curtain air bagsGWarning
Observe "Important safety instructions"
( Y page 38).
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 installed into
the side of the roof frame and run from the
front door (A-pillar) to the rear windows (D-
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
The window curtain air bags will not deploy in
impacts which do not exceed the system's
preset thresholds. You will then be protected
by the fastened seat belts.
Occupant classification system (OCS)
How the Occupant Classification
System works
The Occupant Classification System (OCS) is
standard equipment in the USA.
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. When the 42 indicator
lamp is illuminated, the front-passenger front
air bag is deactivated.
The system does not disable:
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), the front passenger's
weight category, as determined by OCS, will
not be accurate.
Furthermore, the occupant weight may
appear to increase or decrease due to the
following:
R objects hanging on the seat
R objects lodged under the seat
R objects lodged between the seat and the
center console
R objects lodged between the seat and the
door
R other passengers pushing the seat
R objects applying pressure to the back of
the seat
Make sure that the seat always has clearance
in all directions.
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.42Occupant safetySafety
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GWarning
If the 42 indicator lamp
illuminates 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,
or check whether objects are caught under or
around the seat.
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.
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 six 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 relevant 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 "Air bag display
messages" ( Y page 215).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,
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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
recommend that you always place a child
in a rear-facing child restraint on the rear
seat.
R If 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 isilluminated. 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.
R If 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
R For 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.
In such cases, the OCS may have determined:
R that the seat was unoccupied or occupied
by the weight up to or less than that of a
typical 12-month-old child seated in a
standard child restraint
R that the seat was occupied by a small
individual (e.g. a young teenager or a small
adult) or a child who weighs more than the
weight of 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.44Occupant safetySafety
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If the key has been removed from the ignition
lock or is in position 0, indicator lamp
42 : does not light up.
GWarning
If the red + SRS warning 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 as soon
as possible by qualified technicians. 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:
R Do not place more than 4.4 lb (2 kg) into
the parcel net on the rear of the front-
passenger seat. Otherwise, the OCS may
not be able to properly approximate the
occupant weight category.
R Do not place objects under and/or around
the front-passenger seat.
R Do not hang anything from or attach any
items to the seats.
R Do not store any objects, such as books,
between the front-passenger seat and the
center console or the front-passenger door.
R Do not move the front-passenger seat
backwards against rigid objects.
R Sit with the seat belt properly fastened in a
position that is as upright as possible with
your back against the seat backrest.
R While seated, an occupant should not
position him/herself in such a way as to
cause the occupant's weight to be lifted
from the seat cushion as this may result in
the OCS being unable to correctly
approximate the occupant'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 42 indicator
lamp 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 47).
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.
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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.46Occupant safetySafety
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