2019 MERCEDES-BENZ CLA warning light

Restraint system warning lamp
The functions of the restraint system arechecked after the ignition is switched on and atregular intervals while the engine is running.Therefore, malfunctions can be detected ingood time.
Theurestraint system warning lamp on theinstrument cluster lights up when the ignition isswitched on. It goes out no later than a few sec-onds after the vehicle is started. The compo-nents of the restraint system are in operationalreadiness.
A malfunction has occurred if theurestraintsystem warning lamp:
Rdoes not light up after the ignition is switchedon
Rdoes not go out after a few seconds with theengine running
Rlights up again while the engine is running
GWARNING
If the restraint system is malfunctioning,
restraint system components may be trig-
gered unintentionally or may not deploy as
intended during an accident. This can affect
for example the Emergency Tensioning
Device or the air bag. This poses an increased
risk of injury or even fatal injury.
Have the restraint system checked and
repaired in a qualified specialist workshop as
soon as possible.
PASSENGER AIR BAG indicator lamp
PASSENGER AIR BAG ON indicator lampCandPASSENGER AIR BAG OFF indicator lampDarepart of the Occupant Classification System(OCS).
The indicator lamps display the status of thefront-passenger front air bag.
RPASSENGER AIR BAG ON lights up for 60 sec-onds, subsequently both indicator lamps areoff (PASSENGER AIR BAG ON and OFF): thefront-passenger front air bag is able to deployin the event of an accident.
RPASSENGER AIR BAG OFF lights up: the front-passenger front air bag is deactivated. It willthen not be deployed in the event of an acci-dent.
If the PASSENGER AIR BAG ON indicator lamp isoff, only the PASSENGER AIR BAG OFF indicatorlamp shows the status of the front-passengerfront air bag. The PASSENGER AIR BAG OFFindicator lamp may be lit continuously or be off.
Depending on the person in the front-passengerseat, the front-passenger front air bag musteither be deactivated or enabled; see the fol-lowing points. You must make sure of this bothbefore and during a journey.
RChildren in a child restraint system:whether the front-passenger front air bag isenabled or deactivated depends on the instal-led child restraint system, and the age andsize of the child. Therefore, be sure to observethe notes on the "Occupant ClassificationSystem (OCS)" (Ypage 47) and on "Chil-dren in the vehicle" (Ypage 54). There youwill also find instructions on rearward andforward-facing child restraint systems on thefront-passenger seat.
RAll other persons:depending on the classi-fication of the person in the front-passengerseat, the front-passenger front air bag is ena-bled or deactivated (Ypage 47). Be sure toobserve the notes on "Seatbelts“ (Ypage 41) and "Air bags"(Ypage 45). There you can also find infor-mation on the correct seat position.
Seat belts
Introduction
Seat belts are the most effective means ofrestricting the movement of vehicle occupantsin the event of an accident or the vehicle rollingover. This reduces the risk of vehicle occupantscoming into contact with parts of the vehicleinterior or being ejected from the vehicle. Fur-thermore, the seat belt helps to keep the vehicle
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Requirements
To be classified correctly, the front passengermust sit:
Rwith the seat belt fastened correctly
Rin an almost upright position with their backagainst the seat backrest
Rwith their feet resting on the floor, if possible
If the front passenger does not observe theseconditions, OCS may produce a false classifica-tion, e.g. because the front passenger:
Rtransfers their weight by supporting them-selves on a vehicle armrest
Rsits in such a way that their weight is raisedfrom the seat cushion
If it is absolutely necessary to install a childrestraint system on the front-passenger seat, besure to observe the correct positioning of thechild restraint system. Never place objectsunder or behind the child restraint system, e.g. acushion. The entire base of the child restraintsystem must always rest on the seat cushion ofthe front-passenger seat. The backrest of theforward-facing child restraint system must lie asflat as possible against the backrest of the front-passenger seat.
The child restraint system must not touch theroof or be subjected to a load by the headrestraint. Adjust the angle of the seat backrestand the head restraint position accordingly.
Only then can OCS be guaranteed to functioncorrectly. Always observe the child restraint sys-tem manufacturer's installation and operatinginstructions.
Occupant Classification System opera-
tion (OCS)
CPASSENGER AIR BAG ON indicator lamp
DPASSENGER AIR BAG OFF indicator lamp
The indicator lamps inform you whether thefront-passenger front air bag is deactivated orenabled.
XPress the Start/Stop button once or twice, orturn the SmartKey to positionGorHin theignition lock.The system carries out self-diagnostics.
The PASSENGER AIR BAG OFF and PASSENGERAIR BAG ON indicator lamps must light up simul-taneously for approximately six seconds.
The indicator lamps display the status of thefront-passenger front air bag.
RPASSENGER AIR BAG ON lights up for 60 sec-onds, subsequently both indicator lamps areoff (PASSENGER AIR BAG ON and OFF): thefront-passenger front air bag is able to deployin the event of an accident.
RPASSENGER AIR BAG OFF lights up: the front-passenger front air bag is deactivated. It willthen not be deployed in the event of an acci-dent.
If the PASSENGER AIR BAG ON indicator lamp isoff, only the PASSENGER AIR BAG OFF indicatorlamp shows the status of the front-passengerfront air bag. The PASSENGER AIR BAG OFFindicator lamp may be lit continuously or be off.
If the status of the front-passenger front air bagchanges while the vehicle is in motion, an air bagdisplay message appears in the instrument clus-ter (Ypage 202). When the front-passengerseat is occupied, always pay attention to thePASSENGER AIR BAG OFF indicator lamp. Beaware of the status of the front-passenger frontair bag both before and during the journey.
GWARNING
If the PASSENGER AIR BAG OFF indicator
lamp is lit, the front-passenger front air bag is
disabled. It will not be deployed in the event of
an accident and cannot perform its intended
protective function. A person in the front-
passenger seat could then, for example, come
into contact with the vehicle's interior, espe-
cially if the person is sitting too close to the
dashboard. This poses an increased risk of
injury or even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front-
passenger seat is correct and the front-
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passenger front air bag is enabled or disa-
bled in accordance with the person in the
front-passenger seat
Rthe front-passenger seat has been moved
back as far back as possible.
Rthe person is seated correctly.
Make sure, both before and during the jour-
ney, that the status of the front-passenger
front air bag is correct.
GWARNING
If you secure a child in a rearward-facing child
restraint system on the front-passenger seat
and the PASSENGER AIR BAG OFF indicator
lamp is off, the front-passenger front air bag
can deploy in the event of an accident. The
child could be struck by the air bag. This poses
an increased risk of injury or even fatal injury.
Make sure that the front-passenger front air
bag has been deactivated. The PASSENGER
AIR BAG OFF indicator lamp must be lit.
NEVER use a rearward-facing child restraint
on a seat protected by an ACTIVE FRONT AIR-
BAG in front of it; DEATH or SERIOUS INJURY
to the child can occur.
If the PASSENGER AIR BAG OFF indicator lampstays off, do not install a rearward-facing childrestraint system on the front-passenger seat.You can find more information on OCS under"Problems with the Occupant Classification Sys-tem" (Ypage 51).
GWARNING
If you secure a child in a forward-facing child
restraint system on the front-passenger seat
and you position the front-passenger seat too
close to the dashboard, in the event of an
accident, the child could:
Rcome into contact with the vehicle's inte-
rior if the PASSENGER AIR BAG OFF indi-
cator lamp is lit, for example
Rbe struck by the air bag if the PASSENGER
AIR BAG OFF indicator lamp is off
This poses an increased risk of injury or even
fatal injury.
Always move the front-passenger seat as far
back as possible and fully retract the seat
cushion length. Always make sure that the
shoulder belt strap is correctly routed from
the vehicle belt sash guide to the shoulder
belt guide on the child restraint system. The
shoulder belt strap must be routed forwards
and downwards from the vehicle belt sash
guide. If necessary, adjust the vehicle belt
sash guide and the front-passenger seat
accordingly. Always observe the child
restraint system manufacturer's installation
instructions.
If OCS determines that:
RThe front-passenger seat is unoccupied, thePASSENGER AIR BAG OFF indicator lamplights up after the system self-test andremains lit. This indicates that the front-passenger front air bag is deactivated.
RThe front-passenger seat is occupied by achild of up to twelve months old, in a standardchild restraint system, the PASSENGER AIRBAG OFF indicator lamp lights up after thesystem self-test and remains lit. This indi-cates that the front-passenger front air bag isdeactivated.
But even in the case of a twelve-month-oldchild, in a standard child restraint system, thePASSENGER AIR BAG OFF indicator lamp cango out after the system self-test. This indi-cates that the front-passenger front air bag isactivated. The result of the classification isdependent on, among other factors, the childrestraint system and the child's stature. It isrecommended that you install the childrestraint system on a suitable rear seat.
RThe front-passenger seat is occupied by aperson of smaller stature (e.g. a teenager orsmall adult), the PASSENGER AIR BAG OFFindicator lamp lights up and remains lit afterthe system self-test depending on the resultof the classification or, alternatively, goes out.
-If the PASSENGER AIR BAG OFF indicatorlamp is off, move the front-passenger seat
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as far back as possible. Alternatively, a per-son of smaller stature can sit on a rear seat.
-If the PASSENGER AIR BAG OFF indicatorlamp is lit, a person of smaller statureshould not use the front-passenger seat.
RThe front-passenger seat is occupied by anadult or a person of adult stature, thePASSENGER AIR BAG OFF indicator lampgoes out after the system self-test. This indi-cates that the front-passenger front air bag isactivated.
If children are traveling in the vehicle, be sure toobserve the notes on "Children in the vehicle"(Ypage 54).
When the Occupant Classification System(OCS) is malfunctioning, the redurestraintsystem warning lamp on the instrument clusterand the PASSENGER AIR BAG OFF indicatorlamp light up simultaneously. The front-passenger front air bag is deactivated in thiscase and does not deploy during an accident.Have the Occupant Classification System (OCS)checked and repaired immediately at a qualifiedspecialist workshop. Mercedes-Benz recom-mends that you use an authorized Mercedes-Benz Center for this purpose.
If the front-passenger seat, the seat cover or theseat cushion are damaged, have the necessaryrepair work carried out at a qualified specialistworkshop. Mercedes-Benz recommends thatyou use an authorized Mercedes-Benz Centerfor this purpose.
For safety reasons, Mercedes-Benz recom-mends that you only use seat accessories thathave been approved by Mercedes-Benz.
If the driver's air bag deploys, this does notmean that the front-passenger front air bag willalso deploy. The Occupant Classification Sys-tem (OCS) categorizes the occupant on thefront-passenger seat. Depending on that result,the front-passenger front air bag is either ena-bled or deactivated.
Self-check
GDANGER
If the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps do
not both light up during the self-test, the sys-
tem is malfunctioning. The front-passenger
front air bag might be triggered unintention-
ally or might not be triggered at all in the event
of an accident with high deceleration. This
poses an increased risk of injury or even fatal
injury.
In this case the front-passenger seat may not
be used. Do not install a child restraint system
on the front-passenger seat. Have the Occu-
pant Classification System (OCS) checked
and repaired immediately at a qualified spe-
cialist workshop.
GWARNING
If the PASSENGER AIR BAG OFF indicator
lamp remains lit after the self-test, the front-
passenger front air bag is deactivated. It will
not be deployed in the event of an accident. In
this case, the front-passenger front air bag
cannot perform its intended protective func-
tion, e.g. when a person is seated in the front-
passenger seat.
That person could, for example, come into
contact with the vehicle's interior, especially
if the person is sitting too close to the dash-
board. This poses an increased risk of injury or
even fatal injury.
When the front-passenger seat is occupied,
always ensure that:
Rthe classification of the person in the front-
passenger seat is correct and the front-
passenger front air bag is enabled or deac-
tivated in accordance with the person in the
front-passenger seat
Rthe person is seated properly with a cor-
rectly fastened seatbelt
Rthe front-passenger seat has been moved
as far back as possible
If the PASSENGER AIR BAG OFF indicator
lamp remains lit when it should not, the front-
passenger seat must not be used. Do not
install a child restraint system on the front-
passenger seat. Have the Occupant Classifi-
cation System (OCS) checked and repaired
immediately at a qualified specialist work-
shop.
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GWARNING
Objects between the seat surface and the
child restraint system could affect OCS oper-
ation. This could result in the front-passenger
air bag not functioning as intended during an
accident. This poses an increased risk of
injury or even fatal injury.
Do not place any objects between the seat
surface and the child restraint system. The
entire base of the child restraint system must
always rest on the seat cushion of the front-
passenger seat. The backrest of the forward-
facing child restraint system must, as far as
possible, be resting on the backrest of the
front-passenger seat. Always comply with the
child restraint system manufacturer's instal-
lation instructions.
After the self-test, the PASSENGER AIR BAG OFFor the PASSENGER AIR BAG ON indicator lampdisplays the status of the front-passenger frontair bag (Ypage 48). If the front-passenger frontair bag is enabled, the PASSENGER AIR BAG ONindicator lamp lights up for 60 seconds and thengoes out.
If the PASSENGER AIR BAG ON indicator lamp isoff, only the PASSENGER AIR BAG OFF indicatorlamp displays the status of the front-passengerfront air bag. The PASSENGER AIR BAG OFFindicator lamp may be lit continuously or be off.
For more information about the OCS, see "Prob-lems with the Occupant Classification System"(Ypage 51).
Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 50).
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ProblemPossible causes/consequences andPPSolutions
The PASSENGER AIRBAG OFF indicator lamplights up and remains lit,even though the front-passenger seat is occu-pied by an adult or a per-son of a stature corre-sponding to that of anadult.
The classification of the person on the front-passenger seat is incor-rect.
XMake sure the conditions for a correct classification of the personon the front-passenger seat are met (Ypage 48).
XIf the PASSENGER AIR BAG OFF indicator lamp remains lit, the front-passenger seat may not be used.
XHave OCS checked as soon as possible at an authorized Mercedes-Benz Center.
The PASSENGER AIRBAG OFF indicator lampdoes not light up and/ordoes not stay on.
The front-passenger seatis:
Runoccupied
Roccupied by theweight of a child up totwelve months old in achild restraint system
OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and the childseat.
XMake sure that the entire base of the child restraint system rests onthe seat cushion of the front-passenger seat. The backrest of theforward-facing child restraint system must lie as flat as possibleagainst the backrest of the front-passenger seat. If necessary,adjust the position of the front-passenger seat.
XMake sure that the seat cushion length is fully retracted.
XWhen installing the child restraint system, make sure that the seatbelt is tight. Do not pull the seat belt tight using the front-passengerseat adjustment. This could result in the seat belt and the childrestraint system being pulled too tightly.
XCheck for correct installation of the child restraint system.
Make sure that the head restraint does not apply a load to the childrestraint system. If necessary, adjust the head restraint accord-ingly.
XMake sure that no objects are applying additional weight onto theseat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains off and/orthe PASSENGER AIR BAG ON indicator lamp lights up, do not installa child restraint system on the front-passenger seat. It is recom-mended that you install the child restraint system on a suitable rearseat.
XHave OCS checked as soon as possible at an authorized Mercedes-Benz Center.
Deployment of Emergency Tensioning
Devices and air bags
Important safety notes
GWARNING
The air bag parts are hot after an air bag has
been deployed. There is a risk of injury.
Do not touch the air bag parts. Have a
deployed air bag replaced at a qualified spe-
cialist workshop as soon as possible.
GWARNING
A deployed air bag no longer offers any pro-
tection and cannot provide the intended pro-
tection in an accident. There is an increased
risk of injury.
Have the vehicle towed to a qualified special-
ist workshop in order to have a deployed air
bag replaced.
It is important for your safety and that of yourpassenger to have deployed air bags replaced
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and to have any malfunctioning air bagsrepaired. This will help to make sure the air bagscontinue to perform their protective function forthe vehicle occupants in the event of a crash.
GWARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Have pyrotechnically triggered Emergency
Tensioning Devices replaced immediately at a
qualified specialist workshop.
If Emergency Tensioning Devices are triggeredor air bags are deployed, you will hear a bang,and some powder may also be released. Theurestraint system warning lamp lights up.
Only in rare cases will the bang affect your hear-ing. The powder that is released generally doesnot constitute a health hazard, but it may causeshort-term breathing difficulties in people withasthma or other respiratory problems. Providedit is safe to do so, you should leave the vehicleimmediately or open the window in order to pre-vent breathing difficulties.
Air bags and pyrotechnic Emergency TensioningDevices (ETDs) contain perchlorate material,which may require special handling and regardfor the environment. National guidelines mustbe observed during disposal. In California, seewww.dtsc.ca.gov/HazardousWaste/Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, the restraintsystem control unit evaluates important physi-cal data relating to vehicle deceleration or accel-eration, such as:
Rduration
Rdirection
Rintensity
Based on the evaluation of this data, therestraint system control unit triggers the Emer-gency Tensioning Devices during a head-on orrear-end collision.
An Emergency Tensioning Device can only betriggered, if:
Rthe ignition is switched on
Rthe components of the restraint system areoperational. You can find further informationunder "Restraint system warning lamp"(Ypage 41)
Rthe seat belt buckle tongue has engaged inthe belt buckle of the respective front seat
The Emergency Tensioning Devices in the rearpassenger compartment are triggered inde-pendently of the lock status of the seat belts.
If the restraint system control unit detects amore severe accident, further components ofthe restraint system are activated independ-ently of each other in certain frontal collisionsituations:
RFront air bags as well as driver's and front-passenger knee bags
RWindow curtain air bag, if the system deter-mines that deployment can offer additionalprotection to that provided by the seat belt
Depending on the person in the front-passengerseat, the front-passenger front air bag is eitherdisabled or enabled. The front-passenger frontair bag can be deployed in an accident only if thePASSENGER AIR BAG OFF indicator lamp is off.Observe the information on the PASSENGER AIRBAG indicator lamps (Ypage 41).
Your vehicle has two-stage front air bags. At thefirst deployment threshold the front air bag fillswith gas. If the second deployment threshold isthen reached within a few milliseconds, the frontair bag is filled with the maximum quantity ofgas.
The activation threshold of the Emergency Ten-sioning Devices and the air bags is determinedby evaluating the rate of vehicle deceleration oracceleration which occurs at various points inthe vehicle. This process is pre-emptive innature. Deployment should take place in goodtime at the start of the collision.
The rate of vehicle deceleration or accelerationand the direction of the force are essentiallydetermined by:
Rthe distribution of forces during the collision
Rthe collision angle
Rthe deformation characteristics of the vehicle
Rthe characteristics of the object with whichthe vehicle has collided
Factors which can only be seen and measuredafter a collision has occurred do not play a deci-
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sive role in the deployment of an air bag. Nor dothey provide an indication of air bag deploy-ment.
The vehicle can be deformed considerably, with-out an air bag being deployed. This is the case ifonly parts which are relatively easily deformedare affected and the rate of deceleration is nothigh. Conversely, air bags may be deployed eventhough the vehicle suffers only minor deforma-tion. This is the case if, for example, very rigidvehicle parts such as longitudinal body mem-bers are hit, and sufficient deceleration occursas a result.
If the restraint system control unit detects a sideimpact or if the vehicle rolls over, the applicablecomponents of the restraint system aredeployed independently of each other depend-ing on the apparent type of accident.
RSide impact air bags on the side where theimpact takes place, independently of theEmergency Tensioning Device and the use ofthe seat belt on the driver's seat and outerseats in the second row
The side impact air bag on the front-passenger side deploys under the followingconditions:
-the OCS system detects that the front-passenger seat is occupied or
-the seat belt buckle tongue is engaged inthe belt buckle of the front-passenger seat
RWindow curtain air bag on the side of impact,independently of the use of the seat belt andindependently of whether the front-passenger seat is occupied
REmergency Tensioning Devices, if the systemdetermines that deployment can offer addi-tional protection in this situation
RWindow curtain air bags on the driver's andfront-passenger side in certain situationswhen the vehicle rolls over, if the systemdetermines that deployment can offer addi-tional protection to that provided by the seatbelt
iNot all air bags are deployed in an accident.The different air bag systems work independ-ently of each other.
How the air bag system works is determinedby the severity of the accident detected,especially the vehicle deceleration or accel-eration and the apparent type of accident:
RHead-on collision
RSide impact
RRollover
Automatic measures after an acci-
dent
Immediately after an accident, the followingmeasures are implemented, depending on thetype and severity of the impact:
Rthe hazard warning lamps are switched on
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rthe engine is switched off and the fuel supplyis cut off
Rvehicles with Mercedes me connect: auto-matic emergency call
Children in the vehicle
Important safety notes
Accident statistics show that children securedin the rear seats are safer than children securedin the front-passenger seat. For this reason,Mercedes-Benz strongly advises that you installa child restraint system on a rear seat. Childrenare generally better protected there.
If a child younger than twelve years old andunder 5 ft (1.50 m) in height is traveling in thevehicle:
Ralways secure the child in a child restraintsystem suitable for Mercedes-Benz vehicles.The child restraint system must be appropri-ate to the age, weight and size of the child.
Rbe sure to observe the instructions and safetynotes in this section in addition to the childrestraint system manufacturer's installationinstructions.
Ralways observe the instructions and safetynotes on the "Occupant classification system(OCS)". (Ypage 47)
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