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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 the OCS
For more information on air bag display
messages in the multifunction display, see
( Y page 455).GWarning!
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. 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 appropriate
infant restraint, toddler restraint, or booster
seat recommended for the size and weight of
the child.
The infant or child restraint 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 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. 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
completely eliminate this risk is to never
place a child in a rear-facing child restraint
in the front seat. We therefore strongly
recommend that you always place a child
in a rear-facing child restraint in a backseat.
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. 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.
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injured or even killed if the front passenger
front air bag inflates.
RIf you have to 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, and secure child restraint with
the vehicle’s seat belt according to the child
seat manufacturer’s instructions. For
children larger than the typical 12-month-
old child, the front passenger front air bag
may or may not be 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
Rthat the seat was empty or occupied by the
weight up to or less than that of a typical
12-month-old child seated in a standard
child restraint – both of which are instances
where the system suppresses deployment
of the front passenger front air bag even
though the impact met the criteria and was
of sufficient severity to deploy the driver
front air bag
Rthat the seat was occupied by a small
individual (such as 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 – both of
which are instances where the system may
suppress deployment of the front
passenger front air bag even though the
impact met the criteria and was of
sufficient severity to deploy the driver front
air bag
42 indicator lamp : will be
illuminated, except with the SmartKey
removed from the starter switch or with the
starter switch in position 0.
GWarning!
If the red SRS indicator lamp 6 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.
RWhile 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.
RRead and observe all warnings in this
chapter.
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OCS Self-test
After turning the SmartKey in the starter
switch to position 1 or 2 or pressing the
KEYLESS-GO start/stop button once or
twice, the 42 indicator lamp
illuminates. If an adult occupant is properly
sitting on the front passenger seat and the
system classifies the occupant as an adult,
the 42 indicator lamp will
illuminate and go out after approximately
6 seconds.
If the seat is not occupied and the system
classifies the front passenger seat as being
empty, the 42 indicator lamp
will illuminate and not go out.
GWarning!
If the 42 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 the “Practical
hints” section ( Y page 498).
GWarning!
Never place anything between seat cushion
and child seat (e.g. pillow), since it reduces
the effectiveness of the OCS. The bottom and
back of the child seat must make full contact
with the passenger seat cushion and
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 seats.
Seat belts
Safety notes
The use of seat belts and infant and child
restraint systems is required by law in all 50
states, the District of Columbia, the U.S.
territories and all Canadian provinces.
Even where this is not the case, all vehicle
occupants should have their seat belts
fastened whenever the vehicle is in motion.
i See “Children in the vehicle”
( Y page 56) for information on
R infants and children traveling with you in
the vehicle
R restraint systems for infants and children
GWarning!
Always fasten your seat belt before driving off.
Always make sure all of your passengers are
properly restrained. You and your passengers
should always wear seat belts.
Failure to wear and properly fasten and
position your seat belt greatly increases your
risk of injuries and their likely severity in an
accident.
If you are ever in an accident, your injuries can
be considerably more severe without your
seat belt properly buckled. Without your seat
belt buckled, you are much more likely to hit
the interior of the vehicle or be ejected from
it. You can be seriously injured or killed.
In the same crash, the possibility of injury or
death is lessened if you are properly wearing
your seat belt. The air bags can only protect
as intended if the occupants are properly
wearing their seat belts.
GWarning!
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck. That could cause serious
or even fatal injuries. The seat backrest and
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seat belt provide the best restraint when the
wearer is in a position that is as upright as
possible and the seat belt is properly
positioned on the body.GWarning!
Never let more people ride in the vehicle than
there are seat belts available. Make sure
everyone riding in the vehicle is correctly
restrained with a separate seat belt. Never
use a seat belt for more than one person at a
time.
GWarning!
Damaged seat belts or seat belts that have
been subjected to stress in an accident must
be replaced. Also, the seat belt anchoring
points must be checked.
Only use seat belts which have been approved
by Mercedes-Benz.
Do not make any modifications to the seat
belts. This can lead to unintended activation
of the ETDs or to their failure to activate when
necessary.
Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
Have all work carried out only by qualified
technicians. Contact an authorized
Mercedes-Benz Center.
Proper use of seat belts
GWarning!
USE SEAT BELTS PROPERLY
R Seat belts can only protect when used
properly. Never wear seat belts in any other
way than as described in this section, as
that could result in serious injuries in case
of an accident.
R Each occupant should wear their seat belt
at all times, because seat belts help reduce
the likelihood of and potential severity of
injuries in accidents, including rollovers.
The integrated restraint system includes
SRS (driver front air bag, front passenger
front air bag, side impact air bags, window
curtain air bags for door windows),
Emergency Tensioning Devices (ETDs),
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, against 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 fitted
snugly. Take special care of this when
wearing loose clothing.
R Never use a seat belt for more than one
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around a person and another person or
other objects at the same time.
RSeat 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.
RPregnant 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.
RPlace the seat backrest in a position that is
as upright as possible.
RCheck your seat belt during travel to make
sure it is properly positioned.
RNever place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
RWhen 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 the seat belts
GWarning!
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. 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 infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child. For additional
information, see “Children in the vehicle”.
A child’s risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
XWith a smooth motion, pull the seat belt out
of seat belt outlet :.
XPlace the shoulder portion of the seat belt
across the top of your shoulder and the lap
portion across your hips.
XPush latch plate ; into buckle = until it
clicks.
Seat belt adjustment function: The seat
belts on both front seats adjust to the
upper body automatically as necessary
(Y page 52).
XIf necessary, adjust the seat belt to the
correct height (Y page 52).
XIf necessary, tighten the lap portion to a
snug fit by pulling shoulder portion up.
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All lap/shoulder belts except the driver’s seat
belt have special seat belt retractors to
secure child restraints properly. For more
information on special seat belt retractors,
see “Infant and child restraint systems”
(Y page 57).
To release the seat belt with seat belt release
button ?, see (Y page 52).
Seat belt outlet height adjustment
XRaising: Slide the seat belt outlet height
adjuster upward.
The seat belt outlet height adjuster
engages in different positions.
XLowering: Press and hold release
button :.
XSlide the seat belt outlet height adjuster
downward.
XRelease release button : and make sure
the seat belt outlet height adjuster engages
into place.
The seat belts for the rear outer seats are
adjusted automatically.
Seat belt adjustment function
Depending on vehicle production date, your
vehicle may be equipped with this function.
The seat belt adjustment function adjusts the
seat belts on both front seats to the upper
body of the respective vehicle occupant. The
seat belt will be pulled slightly tighter for that
purpose when
Ryou engage the latch plate into the buckle
and then turn the SmartKey in the starter
switch to position 2
Rthe SmartKey in the starter switch is in
position 2 and you then engage the latch
plate in the buckle
The seat belt adjustment function takes place
with a certain amount of retracting force
when the system senses slack between the
vehicle occupant and the seat belt. Do not
retain the seat belt during this procedure. You
can activate or deactivate the seat belt
adjustment function via the control system
(Y page 236).
Releasing the seat belts
XPress seat belt release button ?
(Y page 51).
Allow the retractor to completely rewind
the seat belt by guiding latch plate ;
(Y page 51).
! Make sure the seat belt retracts
completely. Otherwise the seat belt and/or
latch plate could get caught or pinched in
the door or in the seat mechanism. This can
damage the seat belt and impair its
effectiveness, and/or cause damage to the
door and/or door trim panel. Such damage
is not covered by the Mercedes-Benz
Limited Warranty.
Damaged seat belts must be replaced.
Contact an authorized Mercedes-Benz
Center.
Enhanced seat belt reminder system
When the engine is started, the seat belt
telltale 7 will always illuminate for
6 seconds to remind you and your passengers
to fasten your seat belts.
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If the driver’s seat belt is not fastened when
the engine is started, an additional warning
chime will sound. The warning chime goes out
after approximately 6 seconds or once the
driver’s seat belt is fastened.
If after these 6 seconds the driver’s or the
front passenger’s seat belt (with the front
passenger seat occupied) is not fastened with
front doors closed,
R the seat belt telltale 7 remains
illuminated for as long as either the driver’s
or front passenger’s seat belt is not
fastened.
R and if the vehicle speed once exceeds
15 mph (25 km/h), the seat belt telltale
7 starts flashing and a warning chime
sounds with increasing intensity for a
maximum of 60 seconds or until the
driver’s and front passenger’s seat belt are
fastened.
If you and/or your passenger release the
seat belt during driving, the seat belt
telltale 7 starts flashing and the
warning chime sounds as described before.
If the driver’s or the front passenger’s seat
belt remains unfastened after 60 seconds,
the warning chime stops sounding, the seat
belt telltale 7 stops flashing but
continues to be illuminated.
After a vehicle standstill, the warning chime
is reactivated and the seat belt telltale
7 is flashing again if the vehicle speed
once exceeds 15 mph (25 km/h).
The seat belt telltale 7 will only go out if
both the driver’s and the front passenger’s
seat belt (with the front passenger seat
occupied) are fastened, or the vehicle is
standing still and a front door is opened.
For more information, see “Practical hints”
( Y page 493).Emergency Tensioning Device (ETD),
seat belt force limiter
The seat belts for the front seats and rear
outer seats are equipped with ETDs and seat
belt force limiters.
The ETDs are designed to activate in the
following cases:
R in frontal or rear-end impacts exceeding
the system’s preset deployment threshold
R in side impacts exceeding the system’s
preset deployment threshold on the far
side of the impact
R in certain vehicle rollovers
R if the restraint systems are operational and
functioning correctly, see “SRS indicator
lamp” ( Y page 40)
The ETDs for the front seats will only activate
if the front seat belts are fastened (latch plate
properly inserted into buckle).
The ETDs for the rear outer seats will activate
with or without the respective seat belts
fastened.
In an impact, the ETDs remove slack from the
seat belts in such a way that the seat belts fit
more snugly against the body. Seat belt force
limiters, when activated, are employed to
help reduce the peak force exerted by the
seat belts on occupants during a crash.
i The ETDs do not correct an incorrect seat
position or incorrectly worn seat belts.
The ETDs do not pull occupants back
toward the seat backrest.
GWarning!
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Benz Center.
The PRE-SAFE ®
system has electrically
operated reversible pre-tensioners that do
not require replacement after activation.
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Automatic comfort-fit feature seat belt
The automatic comfort-fit feature reduces the
retracting force of the seat belts when they
are in normal use. It is available for the front
seats and for the rear outer seats (only for
vehicles with rear power seats).
Preventive occupant safety (PRE-
SAFE ®
)
GWarning!
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.
The PRE-SAFE ®
system takes preventive
measures to better protect the occupants
from the possibility of personal injuries in the
following hazardous situations:
R emergency braking situations, e.g. if the
Brake Assist System (BAS) ( Y page 64) is
activated
or when
vehicles with DISTRONIC PLUS:
the BAS PLUS ( Y page 64) or the PRE-
SAFE ®
Brake ( Y page 69) is strongly
engaging
R when the radar sensors recognize the
immediate risk of collision in certain
situations (vehicles with DISTRONIC PLUS)
R critical dynamic driving situations, e.g.
when the vehicle has been caused to
understeer or oversteer because it has
exceeded its physical limitations or in case
of evasive steering maneuvers at speeds
above approximately 85 mph (140 km/h)
The PRE-SAFE ®
system takes the following
measures when it is activated:
R The front seat belts are pre-tensioned
automatically.
R If the front passenger seat is in an
unfavorable position, the seat will be
adjusted to a position that seeks to better
protect the occupant.
R If a rear outer power seat (if so equipped)
is in an unfavorable position, the seat will
be adjusted to a position that seeks to
better protect the occupant.
R The system increases the air pressure in
the air pockets (on the sides of the seat
cushion and backrest) of the multicontour
and/or drive-dynamic multicontour front
seats.
R If the vehicle is equipped with multicontour
rear seats, the system increases the air
pressure in the air pockets (on the sides of
the seat backrest) of the multicontour rear
outer seats.
R If the vehicle is in a critical dynamic driving
situation, the door windows and the tilt/
sliding sunroof or panorama roof with tilt/
sliding panel also closes, except for a
minimal gap that remains open.
If the closing procedure of any of these
elements is blocked, it will stop and open
slightly.
Once the hazardous situation no longer exists
and an accident has been avoided, the PRE-
SAFE ®
system loosens the seat belt pre-
tension and decreases the air pressure in the
air pockets of the multicontour and/or drive-
dynamic multicontour seats. All of the PRE-
SAFE ®
system settings can be re-adjusted
following the critical driving event.
If the seat belts do not release:XAdjust the seat backrest to the rear until
the seat belt tension is reduced.
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