2019 MERCEDES-BENZ CLA warning lights

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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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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Driving safety systems
Overview of driving safety systems
In this section, you will find information aboutthe following driving safety systems:
RABS (Anti-lockBrakingSystem)(Ypage 61)
RBAS (BrakeAssistSystem) (Ypage 61)
RActive Brake Assist (Ypage 62)
RESP®(ElectronicStabilityProgram)(Ypage 64)
REBD (ElectronicBrake forceDistribution)(Ypage 67)
RADAPTIVE BRAKE (Ypage 68)
RSTEER CONTROL (Ypage 68)
Important safety notes
If you fail to adapt your driving style or if you areinattentive, the driving safety systems can nei-ther reduce the risk of an accident nor overridethe laws of physics. Driving safety systems aremerely aids designed to assist driving.
You are responsible for maintaining the distanceto the vehicle in front, for vehicle speed, forbraking in good time, and for staying in lane.Always adapt your driving style to suit the pre-vailing road and weather conditions and main-tain a safe distance from the vehicle in front.Drive carefully.
The driving safety systems described only workas effectively as possible when there is ade-quate contact between the tires and the roadsurface. Please pay special attention to thenotes on tires, recommended minimum tiretread depths, etc. (Ypage 291).
In wintry driving conditions, always use wintertires (M+S tires)and if necessary, snow chains.Only in this way will the driving safety systemsdescribed in this section work as effectively aspossible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a way thatthe wheels do not lock when you brake. Thisallows you to continue steering the vehicle whenbraking.
The%ABS warning lamp in the instrumentcluster lights up when the ignition is switchedon. It goes out when the engine is running.
ABS works from a speed of about 5 mph(8 km/h), regardless of road-surface conditions.ABS works on slippery surfaces, even when youonly brake gently.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 61).
GWARNING
If ABS is malfunctioning, the wheels could
lock when braking. The steerability and brak-
ing characteristics would be severely affec-
ted. There is an increased danger of skidding
and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
When ABS is malfunctioning, other systems,including driving safety systems, will alsobecome inoperative. Observe the informationon the ABS warning lamp (Ypage 222)and dis-play messages which may be shown in theinstrument cluster (Ypage 194).
Braking
XIf ABS intervenes:continue to depress thebrake pedal vigorously until the braking sit-uation is over.
XTo make a full brake application:depressthe brake pedal with full force.
If ABS intervenes when braking, you will feel apulsing in the brake pedal.
The pulsating brake pedal can be an indicationof hazardous road conditions, and functions as areminder to take extra care while driving.
BAS (Brake Assist System)
General information
BAS operates in emergency braking situations.If you depress the brake pedal quickly, BASautomatically boosts the braking force, thusshortening the stopping distance.
Driving safety systems61
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SmartKey battery
Important safety notes
GWARNING
Batteries contain toxic and corrosive substan-
ces. If batteries are swallowed, it can result in
severe health problems. There is a risk of fatal
injury.
Keep batteries out of the reach of children. If
a battery is swallowed, seek medical attention
immediately.
The SmartKey batteries contain perchloratematerial, which may require special handlingand regard for the environment. National guide-lines must be observed during disposal. In Cal-ifornia, seewww.dtsc.ca.gov/HazardousWaste/Perchlorate/index.cfm.
Mercedes-Benz recommends that you have thebattery replaced at a qualified specialist work-shop.
Checking the battery
XPress the7or6button.The battery is working properly if batterycheck lampClights up briefly.
The battery is discharged if battery checklampCdoes not light up briefly.
XChange the battery (Ypage 73).
iIf the SmartKey battery is checked withinthe signal reception range of the vehicle,pressing the7or6button:
Rlocks or
Runlocks the vehicle
iYou can get a battery at any qualified spe-cialist workshop.
Replacing the battery
You require a CR 2025 3 V cell battery.
XTake the mechanical key out of the SmartKey(Ypage 72).
XPress mechanical keyDinto the opening inthe SmartKey in the direction of the arrowuntil battery tray coverCopens. When doingso, do not hold coverCshut.
XRemove battery tray coverC.
XRepeatedly tap the SmartKey against yourpalm until battery

iIf you activate the residual heat function athigh temperatures, only the ventilation will beactivated. The blower runs at medium speed.
iYou cannot use the ventilation to cool thevehicle interior to a temperature lower thanthe outside temperature.
Activating/deactivating
XTurn the SmartKey to positionZin the igni-tion lock or remove it (Ypage 123).
XPress theKbutton.The indicator lamp in theKbutton lightsup or goes out.
The indicator lamp in the button indicates thatthe respective function is activated.
iResidual heat is deactivated automatically:
Rafter approximately 30 minutes
Rwhen the ignition is switched on
Rif the battery voltage drops
Air vents
Important safety notes
GWARNING
Very hot or very cold air can flow from the air
vents. This could result in burns or frostbite in
the immediate vicinity of the air vents. There
is a risk of injury.
Make sure that all vehicle occupants always
maintain a sufficient distance to the air out-
lets. If necessary, redirect the airflow to
another area of the vehicle interior.
In order to ensure the direct flow of fresh airthrough the air vents into the vehicle interior,please observe the following notes:
Rkeep the air inlet between the windshield andthe hood free of blockages, such as ice, snowor leaves.
Rnever cover the air vents or air intake grilles inthe vehicle interior.
iFor optimal climate control in the vehicle,open the air vents completely and set theadjusters to the central position.
Setting the air vents
CSide window defroster vent
DSide air vent
XTo open a side air vent:turn the adjuster inside air ventDto the left.
XTo close a side air vent:turn the adjuster inside air ventDclockwise as far as it will go.
iThe center and rear air vents are adjusted inthe same way.
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Climate control
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