
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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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 215).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 215).Occupant safety47SafetyBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+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
According to accident statistics, children are
safer when properly restrained on the rear
seats than on the front-passenger seat. For
this reason, Mercedes-Benz strongly advises
that you always secure children in the rear
seats. 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.
Secure the child restraint system using:
R the vehicle's seat belt
R the seat belt and a Top Tether belt
R the "LATCH" type child seat mount (ISOFIX)
and a Top Tether belt
The child restraint system must be installed
and secured correctly, observing the
manufacturer's installation instructions.
Occupants, especially children, should always
sit as upright as possible, wear the seat belt
properly and use an appropriately 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. Observe the following
important information if it is necessary to
carry a child on the front-passenger seat:
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. If the
child restraint system is installed properly,
the front-passenger front air bag is
deactivated in conjunction with the
BabySmart™ system. Otherwise, the child
could be struck by the air bag when it
inflates in a crash. This could lead to serious
or fatal injury.
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 it is necessary to install a BabySmart™-
compatible rear-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. Should
the 42 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check the 4248Occupant safetySafety
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indicator lamp while driving to make sure
that the 42 indicator lamp is
illuminated. If the 42 indicator
lamp goes out 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
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates.
R If you have to place a child in a forward-
facing child restraint system on the front-
passenger seat, you must:
- 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 instructionsGWarning
When using a BabySmart™-compatible child
restraint system on the front-passenger seat,
the front-passenger front air bag is only
disabled if the 42 indicator lamp
is illuminated.
Check the 42 indicator lamp
repeatedly, every time you use a
BabySmart™-compatible child restraint
system on the front-passenger seat. Should
the 42 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation. If the
42 indicator lamp remains out,
do not use the BabySmart™ child restraint
system to carry a child on the front-passenger
seat until the system has been repaired.
GWarning
The BabySmart™ air bag disabling system
ONLY works with specially adapted child
restraint systems. It does not work with child
restraint systems that are not compatible with
BabySmart™.
Never place anything between the seat
cushion and the child restraint system (e.g. a
cushion), as this reduces the effectiveness of
the BabySmart™ air bag deactivation system.
The underside of the child restraint system
must lie against the seat cushion of the front-
passenger seat. In the event of an accident,
an incorrectly installed child restraint system
could injure the child instead of offering
protection.
Observe the manufacturer's instructions
when installing special child restraint
systems.
Special child restraint systems which are
compatible with BabySmart™ are necessary
for deactivating the front-passenger front air
bag. When the special child restraint system
which is compatible with BabySmart™ is
installed correctly and is recognized by the
sensor system in the front-passenger seat,
the front-passenger front air bag is
deactivated. In this case, 42
indicator lamp : illuminates. If you have any
questions regarding the special child
restraint systems which are compatible with
BabySmart™, consult an authorized
Mercedes-Benz Center.
If the key has been removed from the ignition
lock or is in position 0, indicator lamp
42 : does not light up.
The system does not disable:
R the side impact air bag
R the window curtain air bag
R the Emergency Tensioning Devices
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Problems with the air bag deactivation systemProblemPossible causes/consequences and M SolutionsThe 42
indicator lamp
illuminates and
remains illuminated.A special BabySmart™ compatible child restraint system is
installed on the front-passenger seat.
The front-passenger front air bag is therefore deactivated.A BabySmart™-compatible child restraint system is not installed
on the front-passenger seat. The BabySmart™ system is
malfunctioning.XHave the BabySmart™ system checked as soon as possible at
an authorized Mercedes-Benz Center.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 or does not
remain illuminated with
a BabySmart™-
compatible child
restraint system
properly installed on
the front-passenger
seat.The BabySmart™ system is malfunctioning.XMake sure there is nothing between the seat cushion and the
child seat.XCheck the installation of the child restraint system.XIf the 42 indicator lamp does not illuminate, have
the BabySmart™ system checked as soon as possible at an
authorized Mercedes-Benz Center.
Do not transport a child on the front-passenger seat until the
BabySmart™ system has been repaired.PRE-SAFE ®
systemGWarning!
The PRE-SAFE ®
system is intended to reduce
the effects of an accident on vehicle
occupants who are wearing their seat belt
properly. Despite your vehicle being equipped
with the PRE-SAFE ®
system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated. Therefore,
always drive carefully and adjust your driving
to the prevailing road, weather, and traffic
conditions.
PRE-SAFE ®
takes pre-emptive measures to
protect you in certain hazardous situations.
PRE-SAFE ®
intervenes:
R in emergency braking situations, if the BAS
Brake Assist System intervenes
R in critical driving situations, e.g. if the
vehicle understeers or oversteers severely
when exceeding physical limits or in case
of having to swerve to avoid an obstacle at
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curtain air bags for the side windows),
Emergency Tensioning Devices, seat belt
force limiters, and front seat knee bolsters.
The system is designed to enhance the
protection offered to properly belted
occupants in certain frontal (front air bags
and ETDs) and side (side impact air bags,
window curtain air bags, and ETDs) impacts
which exceed preset deployment
thresholds and in certain rollovers (window
curtain air bags and ETDs).
R Never wear the shoulder belt under your
arm, across your neck or off your shoulder.
In a frontal crash, your body would move
too far forward. That would increase the
chance of head and neck injuries. The seat
belt would also apply too much force to the
ribs or abdomen, which could severely
injure internal organs such as your liver or
spleen.
Adjust the seat belt so that the shoulder
section is located as close as possible to
the middle of the shoulder. It should not
touch the neck. Never pass the shoulder
portion of the seat belt under your arm. For
this purpose, you can adjust the height of
the seat belt outlet.
R Position the lap belt as low as possible on
your hips and not across the abdomen. If
the lap belt is positioned across your
abdomen, it could cause serious injuries in
a crash.
R Never wear seat belts over rigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys etc., as
these might cause injuries.
R Make sure the seat belt is always routed
snugly. Take special care of this when
wearing loose clothing.
R Never use a seat belt for more than one
person at a time. Do not fasten a seat belt
around a person and another person or
other objects at the same time.
R Seat belts should not be worn twisted. In a
crash, you would not have the full width of
the seat belt to distribute impact forces.The twisted seat belt against your body
could cause injuries.
R Pregnant women should also always use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible on
the hips to avoid any possible pressure on
the abdomen.
R Place the seat backrest in a position that is
as upright as possible.
R Check your seat belt during travel to make
sure it is properly positioned.
R Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
R When using a seat belt to secure infant
restraints, toddler restraints, or children in
booster seats, always follow the child seat
manufacturer's instructions.GWarning
Do not pass seat belts over sharp edges. They
could tear.
Do not allow the seat belt to get caught in the
door or in the seat adjustment mechanism.
This could damage the seat belt.
Never attempt to make modifications to seat
belts. This could impair the effectiveness of
the seat belts.
Fastening seat belts
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 seat 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. For additional information, see the
"Children in the vehicle" section.
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Children in the vehicle
Important safety guidelines
GWarning
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. A child's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and the child could be burned on these
parts.
GWarning!
Do not carry heavy or hard objects in the
passenger compartment or trunk unless they
are firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of
R strong braking maneuvers
R sudden changes of direction
R an accident
If an infant or child is traveling in the vehicle:XSecure the child using an infant or child
restraint system appropriate to the age and
weight of the child.XMake sure that the infant or child is
properly secured at all times while the
vehicle is in motion.
Child restraint systems
Important safety guidelines
GWarning
Observe "Important safety instructions"
( Y page 59).
We recommend all infants and children be
properly restrained using the child restraint
systems at all times while the vehicle is in
motion.
The use of infant or child restraints is required
by law in all 50 states, the District of
Columbia, the U.S. territories and all
Canadian provinces.
Infants and small children should always be
seated in an infant or child seat restraint
system appropriate for the size and weight of
the child. They must be properly secured in
accordance with the manufacturer's
installation instructions for the infant or child
seat restraint system. All infant and child seat
restraint systems must comply with the US
Federal Motor Vehicle Safety Standards 213
and 225 and Canadian Motor Vehicle Safety
Standards 213 and 210.2.
A statement by the child restraint
manufacturer of compliance with these
standards can be found on the instruction
label on the restraint system. You will also
find the statement in the instruction manual
provided with the child restraint system.
When using any infant restraint, child
restraint or booster seat, make sure to
carefully read and follow all manufacturer's
instructions for installation and use.
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Please read the warning labels affixed to the
interior of the vehicle or to the infant restraint
or child restraint system.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
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 seriously or even fatally
injured by an air bag deploying. Observe the
following important information if it is
absolutely necessary to carry a child on the
front-passenger seat:
R USA only: Your vehicle is equipped with air
bag technology that is designed to
deactivate the front-passenger front air
bag, when the system on the front-
passenger seat detects the weight of a
typical 12-month old child in a standard
child restraint.
R USA only: For children that weigh more
than a typical 12-month old child, the front-
passenger front air bag can be activated or
deactivated. Always make sure that the
42 indicator lamp is
illuminated indicating that the front-
passenger front air bag is deactivated.
R Canada only: Children 12 years old and
under may ride on the front seat if a
BabySmart™ compatible child restraint
system is installed on the front-passenger
seat. Use only Mercedes-Benz approved
BabySmart™ compatible child restraint
systems. A BabySmart™ compatible child
restraint system will deactivate the front-
passenger front air bag when installed
correctly. The front-passenger front air bag
will not be deactivated if the child restraint
systems that are installed are not
BabySmart™ compatible or if BabySmart™
compatible child restraint systems are not
installed correctly. If the front-passenger
front air bag is deployed in a collision, the
child could be struck by the air bag. This
could lead to serious or fatal injury.
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 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 you must install a rear-facing child
restraint on the front-passenger seat
because circumstances require you to do
so, make sure the 42
indicator lamp is illuminated, indicating
that the front-passenger front air bag is
deactivated. 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 lights up or remains out, you60Children in the vehicleSafety
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