2011 MERCEDES-BENZ M-Class belt

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.
Occupant safety45SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 45Z

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
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 48

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 front-facing 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.GWarning
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.
Always check the 42 indicator
lamp if you are using a BabySmart™-
compatible child restraint system on the
front-passenger seat. 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.
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 Device/belt
buckle tensioner (ETD)
Occupant safety49SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 49Z

Problems with the air bag deactivation systemProblemPossible causes/consequences and M SolutionsCanada only: The
42
indicator lamp is
illuminated constantly.A special BabySmart™ compatible child restraint system is
installed on the front-passenger seat.
The front-passenger front air bag is thus 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 SolutionsCanada only: The
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 restraint system.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 caseOccupant safety51SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 51Z

of having to swerve to avoid an obstacle at
a speed above 85 mph (140 km/h).
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
The NECK-PRO head restraints increase
protection to the driver's and front-
passenger's head and neck. To this end, the
head restraints on the driver's and front-
passenger seats are moved forwards and
upwards in the event of a rear-end collision of
a certain severity. This provides better head
support.GWarning
Do not secure any objects (e.g. coat hangers)
on the NECK-PRO head restraints. Otherwise,
the NECK-PRO head restraints may not
function properly, or in the event of a rear-end
collision may not be able offer the level of
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 model.
Using seat covers and head restraint covers
other than those recommended can prevent/
impair the triggering of NECK-PRO head
restraints and/or the deployment of side
impact air bags in the front.
Contact an authorized Mercedes-Benz Center
for availability.
If the NECK-PRO head restraints have been
triggered in an accident, you must reset the
NECK-PRO head restraints on the driver’s and
front-passenger seat ( Y page 53).
Otherwise, the additional protection will not
be available in the event of another rear-end
collision. You can recognize when NECK-PRO
head restraints have been triggered by the
fact that they have 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.
52Occupant safetySafety
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 52

Resetting triggered NECK-PRO head
restraintsGWarning!
For reasons of safety, have the NECK-PRO
head restraints checked after a rear end
collision at an authorized Mercedes-Benz
Center.
GWarning
If you press the NECK-PRO head restraint
cushion backwards, make sure that your
fingers are not trapped between the cushion
and the cover. Failure to observe could result
in injuries.
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 as far as it will go in the direction of
arrow ;.XFirmly push the NECK-PRO head restraint
cushion backwards in the direction of
arrow = until it engages.XRepeat this procedure for the second
NECK-PRO head restraint.Seat belts
Important safety guidelines
The use of infant or child restraint systems is
required by law in all 50 states, the District of
Columbia, the U.S. territories and all
Canadian provinces.
Even if 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 58) 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
Occupant safety53SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 53Z

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 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's front air bag, front-passenger
front air bag, side impact air bags, window
curtain air bags for door 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 not routed across
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.54Occupant safetySafety
BA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 54

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.
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.GWarning
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 properly. 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.
XAdjust the seat and move the backrest to
an almost vertical position ( Y page 92).XPull the seat belt smoothly through belt
sash guide :.Occupant safety55SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 55Z