2014 MERCEDES-BENZ CLA Owners Manual

REmergency Tensioning Device for the front
seat belts and the outer seat belts in the
rear
RSeat belt force limiter for the front seat
belts and the outer seat belts in the rear
SRS reduces the risk of vehicle occupants
coming into contact with parts of the
vehicle's interior in the event of an accident.
It can also reduce the forces to which vehicle
occupants are subjected during an accident.
SRS warning lamp
GWARNING
If SRS is malfunctioning, child restraint
systemcomponents may be triggered
unintentionally or might not be triggered at all
in the event of an accident with a high rate of
vehicle deceleration. There is an increased
risk of injury, possibly even fatal.
Have SRS checked and repaired immediately
at a qualified specialist workshop.
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
TheSRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
The SRS components are in operational
readiness when theSRS indicator lamp
goes out while the engine is running.
There is a malfunction if:
RtheSRS warning lamp does not light
up when the ignition is switched on
Rthe engine is running and theSRS
warning lamp does not go out after a few
seconds
Rthe engine is running and theSRS
warning lamp lights up again
Triggering of Emergency Tensioning
Devices and air bags
During the first stage of a collision, the air bag
control unit evaluates important physical
data relating to vehicle deceleration or
acceleration, such as:
Rduration
Rdirection
Rmagnitude
Based on the evaluation of this data, the air
bag control unit pre-emptively triggers the
Emergency Tensioning Device in the first
stage.
If there is an even higher rate of vehicle
deceleration or acceleration in a longitudinal
direction, the front air bags are also deployed.
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 enough
propellant gas to reduce the risk of injuries.
The front air bag is fully deployed if a second
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:
Rthe distribution of forces during the
collision
Rthe collision angle
Rthe deformation characteristics of the
vehicle
Rthe characteristics of the object with which
the vehicle has collided
Factors that can only be seen and measured
after a collision has occurred do not play a
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decisive role in the deployment of an air 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.
iThe 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.
iNot all air bags are deployed in an
accident. The differentair 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:
Rhead-on collision
Rside impact
Rrollover
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags
GWARNING
RDamaged 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.
RAir 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. In California, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
RAir bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
RDo not pass seat belts over sharp edges.
They could tear.
RDo not make any modification that could
change the effectiveness of the seat belts.
RDo not bleach or dye seat belts, as this may
severely weaken them. In a crash, they may
not be able to provide adequate protection.
RDo not make any modifications to the SRS
wiring or components.
RDo not modify or remove any components
or parts of the SRS.
RDo not install additional trim material, seat
covers, badges, etc.to the:
-padded steering wheel boss
-knee bag covers
-front-passenger air bag cover
-outer side of front seat bolsters
-outer seat bolsters of the rear bench seat
backrest
-roof frame trim
RDo not install additional electrical/
electronic equipment on or near SRS
components and wiring.
RKeep the area between the air bags and
occupants free of objects(e.g. packages,
handbags, umbrellas etc.).
RDo not hang any objects such as coat
hangers on the coat hooks or the grab
handle above 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.
RAir bag system components will be hot after
an air bag has inflated. Do not touch them.
RNever rest your feet on the dashboard or
the seat. Always keep both feet on the floor
in front of the seat.
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RImproper repairwork 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.
Consult an authorized Mercedes-Benz
Center.
RFor your protection and the protection of
others, when scrapping the air bag unit or
ETD, our safety instructions must be
followed. These are available from any
authorized Mercedes-Benz Center.
RGiven the considerable deployment speed,
required inflation volume, and the material
of the air bags, 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
GWARNING
Using unsuitable seat covers could restrictor
even preventdeployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protectvehicle occupants as
they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
GWARNING
The air bag parts are hot after the airbag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have the
deployed air bags replaced at a qualified
specialist workshop as soon as possible.
GWARNING
Air bags are designed to reduce the potential
of injury and fatality in certain:
Rfrontal impacts (driver's/front-passenger
air bags and knee bags)
Rside impacts (side impact air bags and
window curtain air bags)
Rrollover (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 temporarily comes out of
the air bags. This dust, however, is generally
neither harmful to your health, nor does it
indicate a fire in the vehicle. In order to
preventpotential breathing difficulties, you
may wish to get out of 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.
GWARNING
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.
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As the airbag 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
notwearing 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:
Rsit with the seat belt fastened correctly and
in a position that is as upright as possible
with your back against the backrest.
Rmove 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.
Rdo not lean your head or chest close to the
steering wheel or dashboard.
Ronly 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.
Radjust the front-passenger seat as far back
as possible from the dashboard when the
seat is occupied.
Roccupants, 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.
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 and does not indicate that there
is a fire in the vehicle. The dust might cause
some temporary breathing difficulty for
people with asthma or other breathing
trouble. To avoid this, you may wish to get out
of the vehicle as soon as it is safe to do so.
You can also open the window to allow fresh
air to enter the vehicle interior. TheSRS
warning lamp lights up.
The air bag installation locations are
identified by the AIR BAG symbol.
The air bags are deployed if the air bag control
unit detects the need for deployment.Only in
the event of such a situationwill the air bags
provide their supplemental protection.
If the driverand front passengerdo 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. The
driver and passenger will then be protected
to the extentpossible by a properly fastened
seat belt.Aproperly fastened seat beltis also
needed to provide the best possible
protection in a rollover.
Air bags provide additional protection; they
are not, however, a substitute for seat belts.
All vehicle occupants must fasten their seat
belts regardless of whether your vehicle is
equipped with air bags or not.
It is important for your safety and that of your
passenger to have deployed air bags replaced
and to have any malfunctioning air bags
repaired. This will help to make sure the air
bags continue to perform their protective
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function for the vehicle occupants in the
event of a crash.
iAfter an airbag has been deployed, have
the vehicle towed to the nearestqualified
specialist workshop, evenifyour vehicle is
ready to drive.
Front air bags
Driver's air bagdeploys in front of the
steering wheel; front-passenger front air
bagdeploys 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:
Rat the start of an accident with a high rate
of vehicle acceleration or deceleration in a
longitudinal direction
Rif the system determines that air bag
deployment can offer additional protection
to that provided by the seat belt
Rdepending on whether the seat belt is being
used
Rindependently of other air bags in the
vehicle
If the vehicle rolls over, the front air bags are
generally not deployed.
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 deployment of the front-passenger front
air bag is also influenced by the weight
category of the front passenger, which is
determined by the Occupant Classification
System (OCS) (Ypage 45).
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:
Rthe system, based on the OCS weight
sensor readings, detects that the front-
passenger seat is occupied
Rthe PASSENGER AIR BAG OFF indicator
lamp on the center console is not lit
(Ypage 45)
Rthe air bag control unit predicts a high
impact severity
Knee bags
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Driver's knee bagdeploys underneath the
steering column and front-passenger knee
bagunderneath the glove box. They
deploy together with the front airbags. They
are designed to operate together with the
front air bags in frontal impacts if certain
thresholds are exceeded. The knee bags
operate at best in conjunction with correctly
positioned and fastened seat belts.
Knee bags provide increased protection for
the driver and frontpassenger against the risk
of:
Rknee injuries
Rthigh injuries
Rlower leg injuries
Side impact air bags
GWARNING
Using unsuitable seat coverscould restrictor
even preventdeployment of the air bags
integrated into the seats. Consequently, the
air bags cannot protectvehicle occupants as
they are designed to do. In addition, the
function of the air bag deactivation system
could be restricted. This poses an increased
risk of injury or even fatal injury.
You should only use seat covers that have
been approved for the respective seat by
Mercedes-Benz.
GWARNING
Sensors to control the air bags are located in
the doors. Modifications or work not
performed correctly to the doors or door
paneling, as well as damaged doors, can lead
to the function of the sensors being impaired.
The air bags might therefore not function
properly any more. Consequently, the air bags
cannot protectvehicle occupants as they are
designed to do. There is an increased risk of
injury.
Never modify the doors or parts of the doors.
Always have work on the doors or door
paneling carried out at a qualified specialist
workshop.
You should only use seat covers that have
been approved for your vehicle by Mercedes-
Benz.The seat covers must have a special
tear seam for side impact air bags. Otherwise,
the side impact air bags cannot deploy
correctly and therefore cannot provide the
intended protection in the event of an
accident.
Front side impact air bagsand rear side
impact air bagsdeploy 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:
Rhead
Rneck
Rarms
The side impact air bags are deployed:
Ron the side on which an impact occurs
Rat the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. inaside impact
Rindependently of the use of the seat belt
Rindependently of the front air bags
Rindependently of the ETDs
If the vehicle rolls over, the side impactair
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
impactair bag deploymentcan offer
44Occupant safety
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additional protection to that provided by the
seat belt.
Side impactair bags will not deploy in side
impacts which do not exceed the system's
presetdeployment 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:
ROCS has detected that the front-passenger
seat is unoccupied.
Rthe 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 bagsenhance 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 bagsare 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:
Rat the start of an accident with a high rate
of lateral vehicle deceleration or
acceleration, e.g. inaside impact
Ron the side on which an impactoccurs
Ron the driver's side and passenger side, in
the event of a vehicle rollover and if the
system determines that airbag deployment
can offer the vehicle occupants additional
protection to that provided by the seat belt
Rindependently of the use of the seat belt
Rregardless of whether the front-passenger
seat is occupied
Rindependently of the frontair bags
Window curtain air bagswill not deploy in
the eventofimpacts which do not exceed the
system's presetdeployment thresholds for
vehicle acceleration/deceleration.You will
then be protected by the fastened seat belt.
Occupant Classification System
(OCS)
Method of operation
GWARNING
If theindicator lamp illuminates
when an adult or someone larger than a small
individual is in the front-passenger seat, have
the front passenger reposition himself or
herself in the seat until the
indicator lamp goes out.
In the event of a collision, the air bag control
unit will not allow front-passenger front air
bag deployment when the OCS has classified
the front-passenger seat occupant as
weighing as much as or less than a typical 12-
month-old child in a standard child restraint
or if the front-passenger seat is classified as
being empty.
When the OCS senses that the front-
passenger seat occupant is classified as
being up to or less than the weight of a typical
12-month-old child in a standard child
restraint, theindicator lamp will
illuminate when the engine is started and
remain illuminated, indicating that the front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat is classified as being empty,
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theindicator lamp will illuminate
when the engine is started and remain
illuminated, indicating thatthe front-
passenger front air bag is deactivated.
When the OCS senses that the front-
passenger seat occupant is classified as
being heavier than the weight of a typical 12-
month-old child seated inastandard child
restraint or as being a small individual (such
as a young teenager orasmall adult), the
indicator lamp will illuminate for
approximately6seconds when the engine is
started and then, depending on occupant
weight sensor readings from the front-
passenger seat, remain illuminated or go out.
With theindicator lamp
illuminated, the front-passenger frontair bag
is deactivated. With theindicator
lamp out, the front-passengerfront air bag is
activated.
When the OCS senses that the front-
passenger seat occupant is classified as an
adult or someone larger than a small
individual, theindicator lamp will
illuminate for approximately6seconds when
the engine is started and then go out,
indicating that the front-passenger front air
bag is activated.
If theindicator lamp is illuminated,
the front-passenger front air bag is
deactivated and will not be deployed.
If theindicator lamp is not
illuminated, the front-passenger frontair bag
is activated and will be deployed:
Rin the event of certain frontal impacts
Rif impact exceeds a preset deployment
threshold
Rindependently of the side impact air bags
If the front-passenger front air bag is
deployed, the rate of inflation will be
influenced by:
Rthe rate of relevant vehicle decelerationas
assessed by the air bag control unit
Rthe frontpassenger's weightcategory as
identified by OCS
GWARNING
According to accident statistics, children are
saferwhen properly restrained on the rear
seats than on the front-passenger seat. 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:
RYour 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.
RAchild in a rear-facing child restraint on the
front-passenger seat will be seriously
injured or even killed if the front-passenger
front air bag inflates in a collision which
could occur under some circumstances,
even with the air bag technology installed
in your vehicle. The only means to eliminate
this risk completely is never to place a child
in a rear-facing child restraint in the front-
passenger seat. We therefore strongly
recommend that you always place a child
46Occupant safety
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