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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
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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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System self-test
The 42 indicator lamp
illuminates when you:
R turn the SmartKey to position 1 or 2 in the
ignition lock
R on vehicles with KEYLESS-GO, press the
Start-Stop button once or twice
The 42 indicator lamp goes out
again after approximately six seconds.
If the 42 indicator lamp does not
illuminate or is lit continuously, the system is
malfunctioning. Before transporting a child
on the front-passenger seat, have the
BabySmart™ system checked at an
authorized Mercedes-Benz Center.
For more information, see "Problems with the
air bag deactivation system" section
( Y page 51)
GWarning
Do not place powered-on laptops, mobile
phones, electronic tags such as those used in
ski passes or similar electronic devices on the
front passenger seat. Signals from such
devices may interfere with the BabySmart™
air bag deactivation system. Such signal
interference may cause the 42
indicator lamp not to come on during self-test.
The + SRS indicator lamp and/or the
42 indicator lamp could be
continuously lit, indicating that the system is
not functioning. The front-passenger front air
bag could deploy inadvertently or fail to
deploy in an accident.
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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
a speed above 85 mph (140 km/h).Occupant safety51SafetyBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 51Z
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PRE-SAFE®
takes the following measures
depending on the hazardous situation
detected:
R the front seat belts are pre-tensioned.
R on vehicles with memory functions: the
front-passenger seat is adjusted if it is in an
unfavorable position under accident
conditions.
R if the vehicle skids, the side windows are
closed so that only a small gap remains.
R on vehicles with sliding sunroof: if the
vehicle skids, the sliding sunroof closes so
that only a small gap remains.
If the hazardous situation passes without
resulting in an accident, PRE-SAFE ®
slackens
the belt pretensioning. All settings made by
PRE-SAFE ®
can then be reversed.
If the seat belts are not released:XMove the backrest or the seat back slightly
until the belt pretensioning is reduced.
The locking mechanism releases.GWarning
Make sure that nobody can become trapped
as you adjust the seat.
! Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
More information about belt adjustment, a
convenience function integrated into PRE-
SAFE ®
, can be found in the "Belt adjustment"
section ( Y page 56).
NECK-PRO head restraints/NECK-
PRO luxury head restraints
NECK-PRO head restraints/NECK-PRO luxury
head restraints increase protection of the
driver’s and front-passenger’s head and neck.
In the event of a rear collision of a certain
severity, the NECK-PRO head restraints/
NECK-PRO luxury head restraints on the
driver's and the front-passenger seat are
moved forwards and upwards. This provides
better head support.GWarning
Do not attach any objects (e.g. a coat hanger)
to the NECK-PRO head restraints/NECK-PRO
luxury head restraints. Otherwise, the NECK-
PRO head restraints/NECK-PRO luxury head
restraints may not function properly and in
the event of a rear-end collision may not offer
the protection they are designed to provide.
GWarning
Only use seat covers/head restraint covers
that have been tested and approved by
Mercedes-Benz for your vehicle model.
Using seat covers and head restraint covers
other than those recommended may cause a
malfunction when NECK-PRO head
restraints/NECK-PRO luxury head restraints
are triggered or may prevent side impact air
bags/pelvis air bags from deploying.
Consult an authorized Mercedes-Benz Center
regarding availability.
If the NECK-PRO head restraints/NECK-PRO
luxury head restraints have been triggered in
an accident, reset the NECK-PRO head
restraints/NECK-PRO luxury head restraints
on the driver's and front-passenger seats
( Y page 53). Otherwise, the additional
protection will not be available in the event of
another rear-end collision. NECK-PRO head
restraints/NECK-PRO luxury head restraints
that have been triggered are moved forwards
and can no longer be adjusted.
GWarning!
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation.
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Resetting triggered NECK-PRO head
restraints
Important safety guidelines GWarning
For reasons of safety, have the NECK-PRO
head restraints/NECK-PRO luxury head
restraints checked at an authorized
Mercedes-Benz Center after a rear-end
collision.
GWarning
When pushing back the NECK-PRO head
restraint cushion, make sure your fingers do
not become caught between the head
restraint cushion and the cover. Failure to
observe this could result in injuries.
NECK-PRO head restraints
i Resetting the NECK-PRO head restraints
requires a lot of strength. If you have
difficulty resetting the NECK-PRO head
restraints, have this work carried out at a
qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center.
XTilt the top of the NECK-PRO head restraint
cushion forwards in the direction of
arrow :.XPush the NECK-PRO head restraint cushion
down in the direction of arrow ; as far as
it will go.XFirmly push the NECK-PRO head restraint
cushion back in the direction of arrow =
until the cushion engages.XRepeat this procedure for the second
NECK-PRO head restraint.
NECK-PRO luxury head restraints
i If you have difficulty resetting the NECK-
PRO luxury head restraints, have this work
carried out at a qualified specialist
workshop, e.g. a Mercedes Benz Service
center.
XRemove resetting tool : from the vehicle
document wallet.XSlide resetting tool : into guide ;
between the NECK-PRO luxury head
restraint and the rear cover of the head
restraint.XPush resetting tool : downwards until you
hear the head restraint deployment
mechanism engage.XPull out resetting tool :.XFirmly press the NECK-PRO luxury head
restraint cushion back = until it engages.XRepeat this procedure for the second
NECK-PRO luxury head restraint.XPut resetting tool : back into the vehicle
document wallet.Occupant safety53SafetyBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 53Z
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Seat belts
Important safety guidelines
The use of seat belts, infant or child restraints
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 when the vehicle is in motion.
i See "Children in the vehicle"
( Y page 59) for further information on
infants and children traveling in the vehicle
as well as on child restraint systems.
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
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 and their anchoring points must
also 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.
Correct use of the seat belt
GWarning
USE SEAT BELTS PROPERLY
R Seat belts can only work 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 the
event 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
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