MERCEDES-BENZ M-Class 2011 W164 Service Manual

the rim can 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 bags 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 12 years old and
under must never ride in the front seat,
except in an authorized Mercedes-Benz
child restraint that is compatible with the
BabySmart™ child restraint system. The
BabySmart™ air bag deactivation system
installed in the vehicle will deactivate the
front-passenger front air bag when it is
installed properly. Otherwise, the child
could be struck by the air bag when it
inflates in a crash. This could lead to serious
or fatal injury.
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 airbag
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 offer supplemental protection but
are not a substitute for seat belts. All vehicle
occupants must fasten their seat belts
regardless of whether your vehicle is
equipped with airbags 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 front air bag : deploys in front of
the steering wheel; front-passenger front 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 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 fastened seat belts.
! 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 airbag 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
doors must therefore only be performed by
40Occupant safetySafety
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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 ; deploy 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/belt buckle
tensioners
The side impact air bags are generally not
deployed if the vehicle overturns, unless the
system detects high vehicle deceleration or
acceleration in a lateral direction and
determines that they 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 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.
! 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 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 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)
Operating principles of the Occupant
Classification System
The 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 42 indicator
lamp shows you the current status. If the
42 indicator lamp lights up, 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 Device/belt
buckle tensioner (ETD)
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
The OCS weight sensor is distorted if the
occupant's weight is transferred to another
object in the vehicle, e.g. by leaning on the
armrest.
In addition, the occupant weight may appear
to increase or decrease due to the following:
R objects hanging on the seat
R objects lodged underneath the seat
R objects lodged between the seat and the
center console
R objects lodged between the seat and the
door
R other passengers exerting weight on 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 safety reasons, Mercedes-Benz
recommends that you only use seat
accessories which 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 4 2 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 4 2 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 weighting
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 4 2 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 4 2 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
4 2 indicator lamp will illuminate
for approximately 6 seconds when the engine
is started and then, depending on occupant
weight sensor readings from the seat, remain
illuminated or go out. With the 4
2 indicator lamp illuminated, the
front passenger front air bag is deactivated.
With the 4 2 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 4 2 indicator lamp
will illuminate for approximately 6 seconds
when the engine is started and then goes out,
indicating that the front passenger front air
bag is activated.
If the 4 2 indicator lamp is
illuminated, the front passenger front air bag
is deactivated and will not be deployed.
If the 4 2 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 the OCS
For further information, see "Air bag display
messages" ( Y page 224).GWarning
Accident statistics show that children
secured in the rear seats are safer than
children secured in the front-passenger seat.
For this reason, we strongly advise that you
always secure children in the rear seats.
Regardless of the seat position, children
under 12 years must be secured correctly in
a suitable infant or child restraint system or
booster seat suitable for the size and weight
of the child.
The infant or child restraint system must be
correctly secured using the vehicle's seat
belt, the seat belt and Top Tether belt or the
lower anchorages and the Top Tether belt in
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complete accordance with the child seat
manufacturer's instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be killed or seriously injured by
an inflating air bag. Observe the following
important information if it is absolutely
necessary to carry a child on the front-
passenger seat:
R your vehicle is equipped with air bag
technology designed to deactivate the
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 passenger seat.
R a child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the 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 way to completely rule out this risk
is by making sure you never place a child in
a rearward-facing child restraint system on
the front-passenger seat. For this reason,
we strongly advise that you always carry
children in a rearward-facing child restraint
system on a rear seat.
R if it is absolutely necessary to install a
rearward-facing child restraint system on
the front-passenger seat, make sure the
42 indicator lamp is
illuminated, indicating that the front-
passenger front air bag is disabled. If the
42 indicator lamp does not
light up or goes out when the child restraint
system is installed, check the anchorages
of the restraint system. Check the
42 indicator lamp regularly
while driving to ensure that the
42 indicator lamp is
illuminated. If the 42 indicatorlamp lights up or remains out, you may only
carry a child on the front-passenger seat
once the system has been repaired.
A child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the passenger front air bag
inflates.
R when securing a child in a child restraint
system on the front-passenger seat, you
must:
- move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.
R for children larger than the typical 12-
month-old child, the passenger front air bag
is activated.
Deployment of the driver front air bag does
not mean that the front-passenger front air
bag also should have deployed. The OCS may
have determined:
R that the seat was empty or occupied by a
person with a 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
person (e.g. a young teenager or a small
adult) or a child that weighs more than a
typical 12 month old child in a child
restraint system
These are examples of when OCS disables the
front-passenger front air bag. This occurs
even though the impact fulfills the criteria for
deployment of 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 light up simultaneously, OCS is
malfunctioning. The front-passenger front air
bag is disabled 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 any objects with a total weight
of more than 4.4 lb(2 kg) in the parcel net
on the back of the front-passenger seat.
OCS may otherwise be unable to correctly
assess the occupant's weight category.
R do not place any objects under or near the
front-passenger seat.
R do not hang or fasten any objects on 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 slide the front-passenger seat
backwards against any hard objects.
R sit with the seat belt fastened correctly and
in a position that is as upright as possible
with your back against the 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 bottom 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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Problems with the occupant classification systemProblemPossible causes/consequences and M SolutionsUSA only: The
42
indicator lamp
illuminates and
remains illuminated
when the weight of a
typical adult or an
individual that is the
size of a typical adult
has been detected on
the passenger seat; the
system then
determines the
occupant cannot be a
child.The OCS is malfunctioning.XHave the OCS checked as soon as possible at an authorized
Mercedes-Benz Center.XRead and observe the additional display messages in the
multifunction display ( Y page 224).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
when the weight of a
typical 12-month-old
child in a standard child
restraint or less/
unoccupied child
restraint has been
detected on the front-
passenger seat.The OCS 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.XMake sure there are no objects applying additional weight onto
the seat. Head restraints that press against the roof or books
that are behind or trapped between the seat, for example, apply
force to the seat. OCS senses such forces as additional weight.XIf the 42 indicator lamp does not illuminate, have
the OCS checked as soon as possible at an authorized
Mercedes-Benz Center. Do not transport a child on the front-
passenger seat until the OCS has been repaired.XRead and observe the additional display messages in the
multifunction display ( Y page 224).Occupant safety47SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 47Z

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.
BabySmart™ air bag deactivation
system
How the air bag deactivation system
functions
The BabySmart™ system is standard
equipment in Canada.
GWarning
Accident statistics show that children
secured in the rear seats are safer than
children secured in the front-passenger seat.
For this reason, Mercedes-Benz strongly
advises that you always secure children in the
rear seats. Regardless of the seat position,
children under 12 years must be secured
correctly in a suitable infant or child restraint
system or booster seat suitable for the size
and weight of the child.
Secure the child restraint system with:
R the seat belt of the vehicle
R the seat belt and a Top Tether belt
R the ISOFIX child seat securing system and
a Top Tether belt.
The child restraint system must be installed
and secured correctly, observing the
manufacturer's installation instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt
correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be killed or seriously injured by
an inflating air bag. Observe the following
important information if it is necessary to
carry a child on the front-passenger seat:
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. When the
child restraint system is installed correctly,
the front-passenger front air bag is disabled
in conjunction with the BabySmart™
system installed in the vehicle. If the front-
passenger front air bag is deployed in the
event of a collision, it could hit the child.
This could lead to serious or fatal injuries.
R a child in a rear-facing child restraint on the
passenger seat will be seriously injured or
even killed if the 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 way to completely rule out this risk
is by making sure you never place a child in
a rearward-facing child restraint system on
the front-passenger seat. For this reason,
we strongly advise that you always carry
children in a rearward-facing child restraint
system on a rear seat.
R if it is necessary to install a BabySmart™-
compatible rearward-facing child restraint
system on the front-passenger seat, make
sure the 42 indicator lamp is
illuminated. This indicates that the front-
passenger front air bag is disabled. If the
42 indicator lamp does not
light up or goes out when the child restraint
system is installed, check the anchorages
of the restraint system. Check the
42 indicator lamp regularly
while driving to ensure that the
42 indicator lamp is
illuminated. If the 42 indicator
lamp goes out or remains out, you may only48Occupant safetySafety
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