2011 MERCEDES-BENZ M-Class Indicator

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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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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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)
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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 and like 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 4 2
indicator lamp not to come on during self-test.
The SRS indicator lamp + and/or the
4 2 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.
50Occupant safetySafety
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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

Belt warning for driver and front
passenger
Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the 7 seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out once the driver and
the front passenger have fastened their seat
belts.
If the driver's seat belt is not fastened after
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver or front-
passenger have not fastened their seat belts
and the doors are closed:
R the 7 seat belt warning lamp remains
illuminated as long as either the driver's or
front-passenger seat belt is not fastened.
R if the vehicle speed once exceeds 15 mph
(25 km/h), the 7 seat belt warning
lamp lights up. Additionally, a warning tone
will sound with increasing intensity for a
maximum of 60 seconds or until the
driver's and front-passenger seat belt are
fastened.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front passenger have still not fastened their
seat belt after 60 seconds. The 7 seat belt
warning lamp stops flashing but continues to
be illuminated.
After the vehicle has come to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed has exceeded 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts
or
R the vehicle is stationary and a door is open
i For more information on the 7 seat
belt warning lamp, see "Indicator and
warning lamps in the instrument cluster,
seat belt" ( Y page 248).
Emergency Tensioning Devices and
seat belt force limiters
The front seat belts and the outer seat belts
in the rear are equipped with ETDs and belt
force limiters. In addition, the front seat belts
are installed with belt buckle tensioners.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device/belt buckle tensioner
could be triggered in the event of an
accident.
ETDs/belt buckle tensioners tighten the seat
belts in an accident, pulling them close
against the body.
ETDs/belt buckle tensioners do not correct
incorrect seat positions or incorrectly
fastened seat belts.
ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when activated, are
employed to help reduce the force exerted by
the seat belts on occupants during a crash.
The front belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The ETDs/belt buckle tensioners can only be
activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" ( Y page 36)
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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 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: Children that weigh more than a
typical 12-month old child, the front-
passenger front air bag may be activated/
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, the child could be
killed 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
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 means to eliminate this risk
completely is never to 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 on the 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. 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 that the
42 indicator lamp is
illuminated. If the 42 indicator
lamp goes out or remains out, do not
transport a child on the passenger seat
until 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 If you place a child in a forward-facing child
restraint on the 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
- secure child restraint with the vehicle's
seat belt according to the child seat
manufacturer's instructions
R For children larger than the typical 12-
month-old child, the passenger front air bag
may or may not be activated.GWarning
Infants and small children should never share
a seat belt with another occupant. During an
accident, they could be crushed between the
occupant and seat belt.
A child's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
60Children in the vehicleSafety
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