2019 MERCEDES-BENZ SLC warning lights

Restraint system warning lamp
The functions of the restraint system arechecked after the ignition is switched on andat regular intervals while the engine is running.Therefore, malfunctions can be detected ingood time.
Theurestraint system warning lamp onthe instrument cluster lights up when the igni-tion is switched on. It goes out no later than afew seconds after the vehicle is started. Thecomponents of the restraint system are inoperational readiness.
A malfunction has occurred if theurestraint system warning lamp:
Rdoes not light up after the ignition isswitched on
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 lampCand PASSENGER AIR BAG OFF indicatorlampDare part of the Occupant Classifica-tion System (OCS).
The indicator lamps display the status of thefront-passenger front air bag.
RPASSENGER AIR BAG ON lights up for 60seconds, subsequently both indicator lampsare off (PASSENGER AIR BAG ON and OFF):the front-passenger front air bag is able todeploy in the event of an accident.
RPASSENGER AIR BAG OFF lights up: thefront-passenger front air bag is deactivated.It will then not be deployed in the event ofan accident.
If the PASSENGER AIR BAG ON indicator lampis off, only the PASSENGER AIR BAG OFF indi-cator lamp shows the status of the front-passenger front air bag. The PASSENGER AIRBAG OFF indicator lamp may be lit continu-ously or be off.
Depending on the person in the front-passenger seat, the front-passenger front airbag must either be deactivated or enabled;see the following points. You must make sureof this both before and during a journey.
RChildren in a child restraint system:whether the front-passenger front air bag isenabled or deactivated depends on theinstalled child restraint system, and the ageand size of the child. Therefore, be sure toobserve the notes on the "Occupant Classifi-cation System (OCS)" (Ypage 46) and on"Children in the vehicle" (Ypage 53).There you will also find instructions on rear-ward and forward-facing child restraint sys-tems on the front-passenger seat.
RAll other persons:depending on the classi-fication of the person in the front-passengerseat, the front-passenger front air bag isenabled or deactivated (Ypage 46). Besure to observe the notes on "Seatbelts“ (Ypage 39) and "Air bags"(Ypage 43). 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 roll-ing over. This reduces the risk of vehicle occu-pants coming into contact with parts of thevehicle interior or being ejected from the vehi-cle. Furthermore, the seat belt helps to keep
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passenger front air bag both before and duringthe 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 exam-
ple, come into contact with the vehicle's
interior, especially 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-passenger front air bag is enabled or
disabled 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
AIRBAG 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 child
restraint system on the front-passenger seat.You can find more information on OCS under"Problems with the Occupant ClassificationSystem" (Ypage 49).
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.
Move the front-passenger seat as far back
as possible. Always make sure that the
shoulder belt strap is correctly routed from
the vehicle belt 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 guide.
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 self-test and remains lit.This indicates that the front-passenger frontair bag is deactivated.
RThe front-passenger seat is occupied by achild of up to twelve months old, in a stand-ard child restraint system, the PASSENGERAIR BAG OFF indicator lamp lights up afterthe self-test and remains lit. This indicatesthat the front-passenger front air bag isdeactivated.
But even in the case of a twelve-month-oldchild, in a standard child restraint system,the PASSENGER AIR BAG OFF indicatorlamp can go out after the self-test. This indi-cates that the front-passenger front air bagis activated. The result of the classificationis dependent on, among other factors, thechild restraint system and the child's stat-
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ure. Make sure that the conditions for a cor-rect classification are met. If thePASSENGER AIR BAG OFF indicator lampremains off, do not install a child restraintsystem on the front-passenger seat.
RThe front-passenger seat is occupied by aperson of smaller stature (e.g. a teenager orsmall adult), the PASSENGER AIR BAG OFFindicator lamp either lights up and remainslit after the self-test depending on the resultof the classification or, alternatively, goesout.
-If the PASSENGER AIR BAG OFF indicatorlamp is off, move the front-passenger seatas far back as possible.
-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 corresponding stature,the PASSENGER AIR BAG OFF indicatorlamp goes out after the self-test. This indi-cates that the front-passenger front air bagis activated.
If children are traveling in the vehicle, be sureto observe the notes on "Children in the vehi-cle" (Ypage 53).
When the Occupant Classification System(OCS) is malfunctioning, the redurestraintsystem warning lamp on the instrument clus-ter and the PASSENGER AIR BAG OFF indica-tor lamp 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 aqualified specialist workshop. Mercedes-Benzrecommends that you use an authorizedMercedes-Benz Center for this purpose.
If the front-passenger seat, the seat cover orthe seat cushion are damaged, have the nec-essary repair work carried out at a qualifiedspecialist workshop. Mercedes-Benz recom-mends that you use an authorized Mercedes-Benz Center for this purpose.
For safety reasons, Mercedes-Benz recom-mends that you only use seat accessories thathave been approved by Mercedes-Benz.
Deployment of the driver's air bag does notmean that the front-passenger front air bagdeploys as well. The Occupant ClassificationSystem (OCS) categorizes the occupant on thefront-passenger seat. Depending on that
result, the front-passenger front air bag iseither enabled or deactivated.
Self-check of the Occupant Classifica-
tion System (OCS)
GDANGER
If the PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps do
not both light up during the self-test, the
system is malfunctioning. The front-
passenger front air bag might be triggered
unintentionally 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 Occupant Classification System (OCS)
checked and repaired immediately at a
qualified specialist 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
function, 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
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deactivated in accordance with the per-
son 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
Classification System (OCS) checked and
repaired immediately at a qualified specialist
workshop.
GWARNING
Objects between the seat surface and the
child restraint system could affect OCS
operation. This could result in the front-
passenger air bag not functioning as inten-
ded 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 back-
rest of the front-passenger seat. Always
comply with the child restraint system man-
ufacturer's installation instructions.
After the self-test, the PASSENGER AIR BAGOFF or the PASSENGER AIR BAG ON indicatorlamp displays the status of the front-passenger front airbag (Ypage 46). If thefront-passenger front airbag is enabled, thePASSENGER AIR BAG ON indicator lamp lightsup for 60 seconds and then goes out.
If the PASSENGER AIR BAG ON indicator lampis off, only the PASSENGER AIR BAG OFF indi-cator lamp shows the status of the front-passenger front airbag. The PASSENGER AIRBAG OFF indicator lamp may be lit continu-ously or be off.
For more information about the OCS, see"Problems with the Occupant ClassificationSystem" (Ypage 49).
Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 48).
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ProblemPossible causes/consequences andPPSolutions
The PASSENGER AIRBAG OFF indicator lamplights up and remainslit, even though thefront-passenger seat isoccupied by an adult ora person of a staturecorresponding to that ofan adult.
The classification of the person on the front-passenger seat is incor-rect.
XMake sure the conditions for a correct classification of the per-son on the front-passenger seat are met (Ypage 46).
XIf the PASSENGER AIR BAG OFF indicator lamp remains lit, thefront-passenger seat may not be used.
XHave OCS checked as soon as possible at an authorizedMercedes-Benz Center.
The PASSENGER AIRBAG OFF indicator lampdoes not light upand/or does not stayon.
The front-passengerseat is:
Runoccupied
Roccupied by theweight of a child upto twelve months oldin a child restraintsystem
OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and thechild seat.
XMake sure that the entire base of the child restraint system restson the seat cushion of the front-passenger seat. The backrest ofthe forward-facing child restraint system must lie as flat as possi-ble against the backrest of the front passenger seat. If necessary,adjust the position of the front-passenger seat.
XWhen installing the child restraint system, make sure that theseat belt is tight. Do not pull the seat belt tight using the front-passenger seat adjustment. This could result in the seat belt andthe child restraint 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 thechild restraint system. If necessary, adjust the head restraintaccordingly.
XMake sure that no objects are applying additional weight onto theseat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains offand/or the PASSENGER AIR BAG ON indicator lamp lights up, donot install a child restraint system on the front-passenger seat.
XHave OCS checked as soon as possible at an authorizedMercedes-Benz Center.
Deployment of Emergency Tension-
ing 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 spe-
cialist workshop in order to have a deployed
air bag replaced.
For your own safety and that of your frontpassenger, it is important that you havedeployed air bags replaced and defective airbags repaired. This will help to make sure theair bags continue to perform their protective
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function for the vehicle occupants in the eventof a crash.
GWARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer
operational and are unable to perform their
intended 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.
An electric motor is used by PRE-SAFE®totrigger the tightening of the seat belt in haz-ardous situations. This procedure is reversible.
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 yourhearing. The powder that is released generallydoes not constitute a health hazard, but it maycause short-term breathing difficulties in peo-ple with asthma or other respiratory problems.Provided it is safe to do so, you should leavethe vehicle immediately or open the window inorder to prevent breathing difficulties.
Air bags and pyrotechnic Emergency Tension-ing Devices (ETDs) contain perchlorate mate-rial, which may require special handling andregard for the environment. National guide-lines must be observed during disposal. In Cal-ifornia, seewww.dtsc.ca.gov/HazardousWaste/Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, therestraint system control unit evaluates impor-tant physical data relating to vehicle decelera-tion or acceleration, 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 39)
Rthe seat belt buckle tongue has engaged inthe belt buckle of the respective seat
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
Depending on the person in the front-passenger seat, the front-passenger front airbag is either enabled or disabled. The front-passenger front air bag can be deployed in anaccident only if the PASSENGER AIR BAG OFFindicator lamp is off. Observe the informationon the PASSENGER AIR BAG indicator lamps(Ypage 39).
Your vehicle has two-stage front air bags.
The activation threshold of the EmergencyTensioning Devices and the air bags is deter-mined by evaluating the rate of vehicle decel-eration or acceleration which occurs at variouspoints in the vehicle. This process is pre-emp-tive in nature. Deployment should take placein good time at the start of the collision.
The rate of vehicle deceleration or accelera-tion and the direction of the force are essen-tially determined by:
Rthe distribution of forces during the collision
Rthe collision angle
Rthe deformation characteristics of the vehi-cle
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 adecisive role in the deployment of an air bag.Nor do they provide an indication of air bagdeployment.
The vehicle can be deformed considerably,without an air bag being deployed. This is thecase if only parts which are relatively easilydeformed are affected and the rate of deceler-ation is not high. Conversely, air bags may bedeployed even though the vehicle suffers only
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tem. This confirmation can also be found inthe installation instructions that are includedwith the child restraint system.
Observe the warning labels in the vehicle inte-rior and on the child restraint system.
Child restraint system on the front-
passenger seat
General notes
If you install a child restraint system on thefront-passenger seat, always observe theinstructions and safety notes on the "Occu-pant Classification System (OCS)" (Ypage 46).
You can thus avoid the risks that could ariseas a result of:
Ran incorrectly categorized person in thefront-passenger seat
Rdeactivating the front passenger front airbag unintentionally
Rthe unsuitable positioning of the childrestraint system, e.g. too close to the dash-board
Rearward-facing child restraint system
If circumstances require you to secure a childin a rearward-facing child restraint system onthe front-passenger seat, always make surethat the front passenger front air bag is deacti-vated. Only if the PASSENGER AIR BAG OFFindicator lamp is lit continuously (Ypage 39),is the front passenger front air bag deactiva-ted.
Always observe the child restraint systemmanufacturer's installation and operatinginstructions.
Forward-facing child restraint system
If you secure a child in a forward-facing childrestraint system on the front-passenger seat,always move the front-passenger seat as farback as possible. The entire base of the childrestraint system must always rest on the seatcushion of the front-passenger seat. The back-rest of the child restraint system must lie asflat as possible against the backrest of thefront-passenger seat. The child restraint sys-tem must not touch the roof or be subjectedto a load by the head restraint. Adjust theangle of the seat backrest and the head
restraint position accordingly. Always makesure that the shoulder belt strap is correctlyrouted from the front-passenger seat beltguide to the shoulder belt guide on the childrestraint system. The shoulder belt strap mustbe routed forward and down from the front-passenger seat belt guide.
Always observe the child restraint systemmanufacturer's installation and operatinginstructions.
Pets in the vehicle
GWARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may press buttons
or switches, for instance.
In this way, animals may:
Ractivate vehicle equipment and become
trapped, for example
Rswitch systems on or off and thereby
endanger other road users
Furthermore, unsecured animals may be
flung around inside the vehicle in the event
of an accident or abrupt steering or braking
maneuver, and thereby injure vehicle occu-
pants. There is a risk of accident and injury.
Never leave animals unattended in the vehi-
cle.
Always secure animals properly when driv-
ing, for instance with a suitable pet carrier.
Driving safety systems
Overview of driving safety systems
In this section, you will find information aboutthe following driving safety systems:
RABS (Anti-lockBrakingSystem)(Ypage 57)
RBAS (BrakeAssistSystem) (Ypage 57)
RActive Brake Assist (Ypage 58)
RAdaptive brake lights (Ypage 60)
RESP®(ElectronicStabilityProgram)(Ypage 60)
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REBD (ElectronicBrake forceDistribution)(Ypage 63)
RADAPTIVE BRAKE (Ypage 64)
Important safety notes
If you fail to adapt your driving style or if youare inattentive, the driving safety systems canneither reduce the risk of an accident noroverride the laws of physics. Driving safetysystems are merely aids designed to assistdriving.
You are responsible for maintaining the dis-tance to the vehicle in front, for vehicle speed,for braking in good time, and for staying inlane. Always adapt your driving style to suitthe prevailing road and weather conditions andmaintain a safe distance from the vehicle infront. Drive carefully.
The driving safety systems described onlywork as effectively as possible when there isadequate contact between the tires and theroad surface. Pay particular attention to theinformation regarding tires, recommendedminimum tire tread depths etc. in the "Wheelsand tires" section (Ypage 267).
In wintry driving conditions, always use wintertires (M+S tires) and if necessary, snowchains. Only in this way will the driving safetysystems described in this section work aseffectively as possible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a waythat the wheels do not lock when you brake.This allows you to continue steering the vehi-cle when braking.
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 condi-tions. ABS works on slippery surfaces, evenwhen you only brake gently.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 57).
GWARNING
If ABS is malfunctioning, the wheels could
lock when braking. The steerability and
braking characteristics would be severely
affected. 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 210) anddisplay messages which may be shown in theinstrument cluster (Ypage 183).
Brakes
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 asa reminder 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.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 57).
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