belt MERCEDES-BENZ B-CLASS 2012 User Guide

an accident, the restraint systems on the
front-passenger side might be triggered.
Have triggered
restraint
systems replaced.Driver's air bag
: deploys in front of the
steering wheel; front-passenger front air
bag ; deploys in

front of and above the glove
box.
The front air bags increase protection for the
driver's and front-passenger's head and
chest.
They are deployed:
R at the start of an accident with a high rate
of vehicle acceleration or deceleration in a
longitudinal direction
R in the event of certain frontal impacts
R if the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
R depending on whether the seat belt is being
used
R independently of other air bags in the
vehicle
If the vehicle rolls over, the front air bags are
generally not deployed.
Front-passenger air bag ; is only activated
if the system determines that the front-
passenger seat is occupied. The 4
PASSENGER AIR BAG OFF indicator lamp on
the center console does not light up
(Y page 53). If a child restraint system is installed on the
front-passenger seat and the PASSENGER
AIR BAG OFF
4 indicator lamp on the
center console is not on:
R a child restraint system without a
transponder for the air bag deactivation
system is installed or
R a child
restraint

system with a transponder
has not been installed properly.
Your vehicle has adaptive, two-stage front air
bags. The air bag control unit evaluates
vehicle deceleration or acceleration in the
event of a collision. In the first deployment
stage, the front air bag is filled with part of the
total available propellant gas, thereby
reducing the risk of injury. If the air bag
control unit recognizes within a few
milliseconds that the vehicle is being braked
or accelerated faster than originally
predicted, the front air bag is filled with the
maximum amount of propellant gas available.
The lighter the passenger-side occupant, the
higher the vehicle deceleration rate required
(predicted at the start of the impact) for
second stage inflation of the front-passenger
front air bag. In the second stage, the front
air bags are inflated with the maximum
amount of propellant gas available.
The front air bags are not deployed in
situations where a low impact severity is
predicted. You will then be protected by the
fastened seat belt.
The front-passenger front air bag will only
deploy if:
R the 45 indicator lamp on the center
console is not lit (Y page 53)
R the air bag control unit predicts a high
impact severity Occupant safety
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Driver's knee bag
Driver's knee bag : deploys under the
steering column. The driver's knee bag is
always deployed
along
with the driver's front
air bag. The driver's knee bag is designed to
operate together with the front air bags in
frontal impacts if certain thresholds are
exceeded. The driver's knee bag operates
best in conjunction with correctly positioned
and fastened seat belts.
Driver's knee bag : increases the driver's
protection against:
R knee injuries
R thigh injuries
R lower leg injuries
Side impact air bags G
WARNING
Only use seat covers which have been tested
and approved by Mercedes-Benz for your
vehicle model. Using other seat covers may
interfere with or prevent the deployment of
the side impact air bags. Contact an
authorized Mercedes-Benz Center for
availability. G
WARNING
The pressure sensors for side impact air bag
control are located in the doors. Do not
modify any components of the doors or door
trim panels including, for example, the
addition of door speakers.
Improper repair work on the doors or the
modification or addition

of components to the doors create a risk of rendering the side
impact air bags inoperative or causing
unintended air bag deployment. Work on the
doors must therefore only be performed by
qualified technicians. Contact an authorized
Mercedes-Benz Center.
Front side impact air bags
: and rear side
impact air bags ; deploy next to the outer
seat cushions.
When deployed,
the

side impact air bags offer
additional protection of the thorax for
occupants on the front seats as well as also
of the pelvis for the vehicle occupants on the
side of the vehicle on which the impact
occurs. However, they do not protect the:
R head
R neck
R arms
The side impact air bags are deployed:
R on the side on which an impact occurs
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R independently of the use of the seat belt
R independently of the front air bags
R independently of the ETDs
If the vehicle rolls over, the side impact air
bags are generally not deployed. Side impact
air bags are deployed if the system detects
high vehicle deceleration or acceleration in a
lateral direction and determines that side
impact air bag deployment can offer 44
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additional protection to that provided by the
seat belt.
Side impact air bags will not deploy in side
impacts which do not exceed the system's
preset deployment thresholds for lateral
acceleration/deceleration. You will then be
protected by the fastened seat belt.
The side impact air bag on the front-
passenger side is not deployed in the
following situations:
R
OCS has detected
that the front-passenger
seat is unoccupied.
R the front-passenger seat belt is not
fastened.
The side impact air bag on the front-
passenger side will deploy if the front-
passenger seat belt is fastened, regardless of
whether the front-passenger seat is occupied
or not.
Window curtain air bags Window curtain air bags
: enhance the
level
of protection for the head, but not chest or
arms, of the vehicle occupants on the side of
the vehicle on which the impact occurs.
Window curtain air bags : are integrated
into the side of the roof frame and deployed
in the area from the A-pillar to the C-pillar.
Window curtain air bags are deployed:
R at the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. in a side impact
R on the side on which an impact occurs R
on the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines
that

air bag deployment
can offer the vehicle occupants additional
protection to that provided by the seat belt
R independently of the use of the seat belt
R regardless of whether the front-passenger
seat is occupied
R independently of the front air bags
Window curtain air bags : will not deploy in
the event of impacts which do not exceed the
system's preset deployment thresholds for
vehicle acceleration/deceleration. You will
then be protected by the fastened seat belt. Seat belts
Important safety notes G
WARNING
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. G
WARNING
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 Occupant safety
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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.
G
WARNING
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. G
WARNING
Always have damaged seat belts or seat belts
that have been subjected to a load in an
accident replaced and the anchorages
checked.
Only use seat belts that have been approved
by Mercedes-Benz.
Never tamper with seat belts. This can result
in the unintended deployment of the
Emergency Tensioning Devices or the failure
to deploy when necessary.
Do not bleach or dye seat belts, as this may
severely weaken them. In the event of a
collision, they may be unable to provide
adequate protection.
Have all work carried out only by qualified
technicians. Consult a qualified specialist
workshop.
The use of seat belts and infant and child
restraint systems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
Even where this is not required by law, all
vehicle occupants should correctly fasten
their seat belts before starting the journey. i
See "Children in the vehicle"
(Y page 50) for further information on
infants and children

traveling in the vehicle
as well as on child restraint systems.
Proper use of the seat belts G
WARNING
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, driver's side knee
bag, front-passenger front air bag, side
impact air bags, window 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,
driver's side knee bag 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 not46
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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
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. G
WARNING
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 G
WARNING
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. Occupant safety
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X
Adjust the seat and move the backrest to
an almost vertical position ( Y page 86).
X Pull the seat belt smoothly through belt
sash guide :.
X Without twisting it, guide the shoulder
section of the seat belt across the middle
of your shoulder
and the lap section across
your pelvis.
X Engage belt tongue ; in buckle =.
X If necessary, adjust the seat belt to the
appropriate height ( Y page 48).
X If necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
Information on releasing the seat belt with
release button

?(Y page 48).
Belt height adjustment You can adjust the seat belt height on the
front seats. Adjust the belt to a height that
allows the upper part of the seat belt to be
routed across the center of your shoulder.
X
To raise: slide the belt sash guide upwards.
The belt sash guide engages in various
positions.
X To lower: press and hold belt sash guide
release :

.
X Slide the belt sash guide downwards.
X Release belt sash guide release : and
make sure that the belt sash guide has
engaged. Using the seat belt for the center rear-
compartment seat If the left-hand rear seat backrest is folded
down and
back

up again, the rear center seat
belt may lock. The seat belt can then not be
pulled out.
X To release the rear center seat belt: pull
the seat belt out approximately 1 in
(25 mm) at the belt outlet on the backrest
and then release it again.
The seat belt is retracted and released.
Releasing seat belts !
Make sure
that

the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Visit a qualified specialist
workshop. X
Press release button ?
on belt

buckle =.
X Guide belt tongue ; back to belt sash
guide :.48
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Belt warning for the 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 if the driver and
the front passenger have already fastened
their seat belts.
If the driver's seat belt is not fastened when
the engine is started, an additional warning
tone will sound. This warning tone stops after
a maximum of 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, the 7 seat belt
warning lamp lights up:
R until the driver's or front passenger's seat
belt is fastened
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, a warning tone also sounds with
increasing intensity for a maximum of
60 seconds or until the driver or front-
passenger seat belt has been 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 seat belt has still not been
fastened after 60 seconds. The 7 seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7 seat
belt warning lamp flashes again if the vehicle
speed again exceeds 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 "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Y page 224).
Emergency Tensioning Devices, seat
belt force limiters G
WARNING
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.
! 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 could be triggered in the
event of an accident.
The front seat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices and seat belt force
limiters.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" 6(Y page 39).
R the belt tongue is engaged in the buckle on
each of the front seat belts.
The ETDs on the outside seats in the rear
compartment are triggered independently of
the lock status of the seat belts.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or Occupant safety
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accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R if, in the
event of a side impact, on the side
opposite the impact the vehicle
decelerates or accelerates rapidly in a
lateral direction
R if, in certain situations where the vehicle
rolls over, the system determines that it
can provide additional protection
If the ETDs are deployed, you will hear a bang,
and a small amount of powder may also be
released. Only in rare cases will the bang
affect your hearing. The powder that is
released generally does not constitute a
health hazard. The 6 SRS warning lamp
lights up.
If the seat belt is also equipped with a seat
belt force limiter and this is triggered, the
force exerted by the seat belt on the vehicle
occupant is reduced.
The seat belt force limiters for the front seats
are synchronized with the front air bags,
which take on a part of the deceleration force.
This results in the force exerted on the
occupant being distributed over a greater
area. Children in the vehicle
Child restraint systems
Important safety notes G
WARNING
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 For children larger than the typical
12-month-old child, the front passenger
front air bag may or may not be activated.
Always make sure the 4 5 indicator
lamp is illuminated, indicating that the front
passenger front air bag is deactivated.
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 4 5 indicator
lamp is illuminated, indicating that the front 50
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passenger front air bag is deactivated.
Should the 4 5 indicator lamp not
illuminate or go out while the restraint is
installed, please check installation.
Periodically check
the 4
5 indicator
lamp while driving to make sure the 4
5 indicator lamp is illuminated. If the
4 5 indicator lamp goes out or
remains out, do not transport a child on the
front passenger seat until 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 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. G
WARNING
Infants and small children should never share
a seat belt

with another occupant. In the event
of 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/
or the child is not properly secured in the child
restraint.
Children that are too large for a child restraint
must travel in seats using normal seat belts.
Position the shoulder belt across the chest
and shoulder, not the face or neck. A booster
seat may be necessary to achieve proper seat
belt positioning for children over 41 lbs
(18 kg) until they reach a height where a lap/
shoulder belt fits properly without a booster
seat.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from becoming a projectile in the event of an
accident.
G
WARNING
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. G
WARNING
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 Children in the vehicle
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Further information on secure stowage of
loads can be found under "Loading
guidelines".
If an
infant
or child is traveling in the vehicle:
R Secure the child with a child or infant seat
restraint system appropriate to the age and
weight of the child.
R Make sure that the infant or child is
properly secured at all times while the
vehicle is in motion.
Mercedes-Benz recommends that you always
properly secure all infants and children with
a child or infant seat restraint system for the
trip.
The use of seat belts and infant and child
restraint systems is required by law in:
R all 50 states
R the U.S. territories
R the District of Columbia
R all Canadian provinces
Infants and children must always be seated in
an appropriate infant or child restraint system
recommended for the size and weight of the
child. The infant or child restraint system
must be properly secured in accordance with
the manufacturer's instructions.
All infant or child restraint systems must meet
the following standards:
R U.S. Federal Motor Vehicle Safety
Standards 213 and 225
R Canadian Motor Vehicle Safety Standards
213 and 210.2
Confirmation that the child restraint system
corresponds to the standards can be found
on an instruction label on the child restraint
system. This confirmation can also be found
in the installation instructions that are
included with the child restraint system.
Always read and follow the manufacturer's
instructions when using an infant or child
restraint system or booster seat.
Observe the warning labels in the vehicle
interior or on the infant or child restraint. Child restraint system on the front-
passenger seat G
WARNING
If the front-passenger air bag is not disabled:
R a child secured in a child restraint system
on the front-passenger seat could be
seriously or even

fatally injured by the front-
passenger air bag deploying. This is
especially a risk if the child is in the
immediate vicinity of the front-passenger
air bag when it deploys.
R never secure a child on the front-passenger
seat in a rearward-facing child restraint
system. Only secure a rearward-facing
child restraint system on a suitable rear
seat.
R always move the front-passenger seat to
the rearmost position if you secure a child
in a forward-facing child restraint system
on the front-passenger seat.
The front-passenger air bag is not disabled:
R on vehicles without an air bag deactivation
system on the front-passenger seat.
R on vehicles with an air bag deactivation
system on the front-passenger seat, unless
a child restraint system with transponders
for an air bag deactivation system is
installed on the front-passenger seat
R on vehicles with an air bag deactivation
system on the front-passenger seat, if the
PASSENGER AIR BAG OFF indicator lamp
4 is not lit.
To make you aware of this danger, a
corresponding warning sticker has been
affixed on the dashboard and on both sides of
the sun visor on the front-passenger side.
Information about recommended child
restraint systems is available at any
authorized Mercedes-Benz Center. 52
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