MERCEDES-BENZ B-CLASS SPORTS 2013 Service Manual

deployment threshold is reached within a few
milliseconds.
The Emergency Tensioning Device and air bag
triggering thresholds are variable and are
adapted to the detected rate of deceleration
or acceleration of the vehicle. This process is
pre-emptive in nature. The triggering process
must take place in good time at the start of
the collision.
The rate of vehicle deceleration or
acceleration and the direction of the force are
essentially determined by:
R
the distribution of forces during the
collision
R the collision angle
R the deformation characteristics of the
vehicle
R the characteristics of the objectw ith which
the vehicle has collided
Factors that can only be seen and measured
after a collision has occurred do not play a
decisive role in the deploymen tofanair bag,
nor do they provide an indication of air bag
deployment.
The vehicle may be deformed significantly,
e.g. the hood or the fender, without an air bag
being deployed. This is the case if only parts
which are relatively easily deformed are
affected and the rate of deceleration is not
high. Conversely, air bags may be deployed
even though the vehicle suffers only minor
deformation. This is the case if, for example,
very rigid vehicle parts such as longitudinal
body members are hit, and sufficient
deceleration occurs as a result.
i The front Emergency Tensioning Devices
can only be triggered if the seat belt
tongues on the front seats are correctly
engaged in the seat belt buckles.
i Not all air bags are deployed in an
accident .The different air bag systems
work independently of each other. How the air bag system works is
determined by predicting the severity of
the accident, especially vehicle
deceleration or acceleration, and the type
of accident:
R
head-on collision
R side impact
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts
installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced. PRE-
SAFE ®
has electrically operated reversible
belt tensioners in addition to the
pyrotechnic ETDs.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R 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.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS. 38
Occupant safetySafety

R
Do not install additional trim material, seat
covers, badges, etc. to the:
-padded steering wheel boss
- knee bag covers
- front-passenge rair bag cover
- outer side of front seat bolsters
- outer side of rear bench seat backrest
seat bolsters
- roof lining trim
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area betwee nair bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
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 Improper repair work on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must therefore only be
performed by qualified technicians.
Contact an authorized Mercedes-Benz
Center.
R For your protection and the protection of
others, when scrapping the air bag unit or
ETD, our safety instructions must be
followed. These instructions are available
fro ma ny authorized Mercedes-Benz
Center.
R Given the considerable deployment speed,
required inflation volume, and the material
of the ai rbags, there is the possibility of
abrasions or other, potentially more serious
injuries resulting from air bag deployment. If you sell your vehicle
,Mercedes-Benz
strongly recommends that you inform the
subsequent owner that the vehicle is
equipped with SRS. Also, refer them to the
applicable section in the Operator's Manual. Air bags
Important safety notes G
WARNING
Air bags are designed to reduce the incidence
of injuries and fatalities in certain situations:
R frontal impacts (driver's and front-
passenger fronta ir bags and driver's knee
bag)
R side impacts (side impact air bags and
window curtain air bags)
R rollover (window curtain air bags)
However, no system available today can
completely eliminate injuries and fatalities.
When the air bags are deployed, a small
amount of powder is released .The powder
generally does not constitute a health hazard
and does not indicate that there is a fire in the
vehicle. In order to prevent potential
breathing difficulties, you should leave the
vehicle as soon as it is safe to do so. If you
have any breathing difficulty but cannot get
out of the vehicle after the air bag inflates,
then get fresh air by opening a window or
door. G
WARNING
In order to reduce the potential danger of
injuries caused during the deployment of the
front air bags, the driver and front passenger
must always be correctly seated and wear
their seat belts.
For maximum protection in the event of a
collision, you must always be in the normal
seat position with your back against the
backrest. Fasten your seat belt and make sure
that it is correctly positioned on your body. Occupant safety
39Safety
Z

As the ai
rbag inflates with considerable
speed and force, a proper seating position
and correct positioning of the hands on the
steering wheel will help to keep you at a safe
distance from the air bag. Occupants who are
no tw earing their seat belt, are not seated
properly or are too close to the air bag can be
seriously injured or killed by an air bag, as it
inflates with great force instantaneously:
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 move the driver's seat as far back as
possible, still permitting proper operation
of vehicle controls. The distance from the
center of the driver's chest to the center of
the air bag cover on the steering wheel
must be at least 10 inches (25 cm). You
should be able to accomplish this by
adjusting the seat and steering wheel. If
you have any difficulties, please contact an
authorized Mercedes-Benz Center.
R do not lean your head or chest close to the
steering wheel or dashboard.
R only hold the steering wheel on the outside.
Placing hands and arms inside the rim can
increase the risk and potential severity of
hand/arm injury if the driver front air bag
inflates.
R adjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
R occupants, especially children, should
never place their bodies or lean their heads
in the area of the door where the side
impact air bag inflates .This could result in
serious or fatal injuries should the side
impact air bag be deployed. 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.
Failure to follow these instructions can result
in severe injuries to you or other occupants. If you sell your vehicle, it is important that you
make the buyer aware of this safety
information. Be sure to give the buyer this
Operator's Manual.
G
WARNING
Accident research shows that the safest place
for children in an automobile is in a rear seat.
As ide impact air bag related injury may occur
if occupants, especially children, are not
properly seated or restraine dwhen next to a
side impact air bag which needs to deploy
rapidly in a side impact in order to do its job.
To help avoid the possibility of injury, please
follow these guidelines:
(1) Always sit as upright as possible and use the seat belts properly.
Make sure that children 12 years
old and under use an appropriately
sized child restraint, infant
restraint, or booster seat
recommended for the size and
weight of the child.
(2) Always wear seat belts properly.
If the air bags 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 6SRS warning lamp
lights up.
The air bags are only deployed if the air bag
control unit detects the need for deployment.
Only in the event of such a situation will the
air bags provide their supplemental
protection.
If the driver and front passenger do not wear
their seat belts, it is not possible for the air
bags to provide their supplemental
protection.
In the event of other types of impacts and
impacts below air bag deployment
thresholds, the air bags will not deploy.T he
driver and passengers will then be protected
to the extentp ossible by a properly fastened40
Occupant safetySafety

seat belt.
Aproperly fastened seat belti s also
needed to provide the best possible
protection if the vehicle rolls over.
Air bags are not a substitute for seat belts.
Always wear your seat belt, regardless of
whether or not your vehicle is equipped with
air bags.
It is important for your safety and that of your
passengers to have deployed air bags
replaced and to have any malfunctioning air
bags repaired. This will help to make sure the
air bags will continue to provide supplemental
crash protection for occupants.
Front air bags !
Make sure that there are no objects
exerting force on the front-passenger seat.
This could cause the system to identify the
seat as being occupied, and in the event of
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 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 overturns, the front air bags are
generally not deployed. If the system detects
high vehicle deceleration in alongitudinal
direction, the front air bags are deployed.
Front-passenger air bag ;is only activated
if the system determines that the front-
passenger seat is occupied. The 4
PASSENGER AIRBAG OFF indicator lamp on
the center console does not light up
(Y page 50).
When a child restraint system is installed on
the front-passenger seat and the 4
PASSENGER AIRBAG OFF indicator lamp in
the center console does not light up:
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. Occupant safety
41Safety Z

The front-passenger fronta
ir bag will only
deploy if:
R the 45 indicator lamp in the center
console is not lit (Y page 50).
R the air bag control unit predicts a high
impac tseverity
Driver's knee bag Driver's knee bag
:increases the driver's
protection against:
R knee injuries
R thigh injuries
R lower leg injuries
Driver's knee bag :deploys under the
steering column. If, during a frontal collision,
the system determines that air bag
deployment can offer additional protection to
that provided by the seat belt, driver's knee
bag :is deployed along with the driver's air
bag. Driver's knee bag :operates best in
conjunction with correctly positioned and
fastened seat belts.
Side impact air bags G
WARNING
If you wish to use seat covers, Mercedes-Benz
recommends that, for safety reasons, you
only use seat covers that have been approved
for Mercedes-Benz vehicles.
The seat covers must have a special tear seam
for sidebags. Otherwise, the sidebags cannot
deploy correctly and would fail to provide the
intended protection in the event of an accident. Suitable seat covers can be
obtained, for example, from a Mercedes-Benz
Service Centre.
Example: side impact air bags on the driver's side
Fron
tside impac tair bags :and rear side
impac tair bags ;deploy nex tto the outer
seat cushions.
When deployed, the side impact air bags offer
additional protection for the thorax and, on
the front seats, the pelvis of 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
Window curtain air bags Example: window curtain air bags on the front-
passenger side
Window curtain air bags
:are integrated
into the side of the roof frame and deploy in
the area from the A-pillar to the C-pillar. 42
Occupant safetySafety

When deployed, window curtain air bags
:
increase protection for the heads of vehicle
occupants on the side of the vehicle on which
the impact occurs .However, they do not
protect the:
R chest
R arms
They 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 aside impact
R regardless of whether the front-passenger
seat is occupied
R independently of the use of the seat belt
R independently of the front air bags
Window curtain air bags :will not deploy in
impacts with deceleration rates which do not
exceed the system's prese tdeployment
thresholds for vehicle deceleration or
acceleration. 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
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
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.
The use of infant or child restraints is required
by law in all 50 states, the Districtof Occupant safety
43Safety Z

Columbia, the U.S. territories and all
Canadian provinces.
Even where this is nott
he case, all vehicle
occupants should have their seat belts
fastened when the vehicle is in motion.
i See "Children in the vehicle"
(Y page 47) 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 not
touch the neck.N
ever 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 distribut eimpact forces.
The twisted seat belt against yourb ody
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 44
Occupant safetySafety

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.
Ac hild'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. X
Adjust the seat and move the backrest to
an almost vertical position (Y page 84).
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 45).
X If necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
For more information about releasing the seat
belt with release button ?, see "Releasing
seat belts" (Y page 46).
Belt height adjustment Occupant safety
45Safety Z

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.
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 ;to belt sash
guide :. Belt warning for the driver and front
passenger Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the
7seat belt warning lamp
lights up for six seconds each time the engine
is started. It then goes out if the driver and
the frontp assenger have fastened their seat
belts.
If the driver's seat belt is notf astened when
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 notf astened their seat belts
and the doors are closed, the 7seat belt
warning lamp lights up:
R until the driver's or fron tpassenger's seat
belt is fastened
R once the vehicle has exceeded a speed of
15 mph (25 km/h), in addition a warning
tone will sound with increasing intensity for
up to 60 seconds or until the driver's or
front-passenger seat belt is 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 evenift he driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 7seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated and the 7seat
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. 46
Occupant safetySafety

i
For more information on the 7seat
bel tw arning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Ypage 218).
Emergency Tensioning Devices, belt
force limiters G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed must be renewed.
For your safety, when disposing of Emergency
Tensioning Devices, always observe the
safety instructions. These are available from
any authorized Mercedes-Ben zCenter.
The PRE-SAFE ®
system has electrically
operated reversible pre-tensioners that do
not require replacement after activation.
! 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 fron tseat belts and the outer seat belts
in the rear are equipped with Emergency
Tensioning Devices and 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.
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
occupan tis reduced.
The 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. The ETDs can only be activated when:
R
the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" (Y page 37).
R the belt tongue is engaged in the buckle on
each of the lap-shoulder belts in the front.
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
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R if, in the event of a side impact, the vehicle
is subjected to high lateral acceleration/
deceleration
If the ETDs are deployed, you will hear a bang,
and a small amount of powder may also be
released.O nly in rare cases will the bang
affect your hearing .The powder that is
released generally does not constitute a
health hazard. The 6SRS warning lamp
lights up. 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. Children in the vehicle
47Safety
Z