2019 MERCEDES-BENZ SLC warning light

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
Occupant safety51
Safety
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GWARNING
If you leave children unsupervised in the
vehicle, they could set it in motion by, for
example:
Rrelease the parking brake.
Rshift the automatic transmission out of
the parking positionP.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle.
Never leave children unsupervised in the
vehicle.
GWARNING
If persons, particularly children are subjec-
ted to prolonged exposure to extreme heat
or cold, there is a risk of injury, possibly
even fatal. Never leave children unattended
in the vehicle.
GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight.
Protect it with a blanket, for example. If the
child restraint system has been exposed to
direct sunlight, let it cool down before secur-
ing the child in it. Never leave children unat-
tended in the vehicle.
Always ensure that all vehicle occupants havetheir seat belts fastened correctly and are sit-ting properly. Particular attention must be paidto children.
Observe the safety notes on the seat belt(Ypage 40) and the notes on correct use ofseat belts (Ypage 41).
A booster seat may be necessary to achieveproper seat belt positioning for children over
40 lbs (18 kg) until they reach a height wherea three-point seat belt can be properly fas-tened without a booster seat.
Special seatbelt retractor
GWARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt
retractor is disabled and the inertia real
draws in a portion of the seat belt. The seat
belt cannot be immediately refastened.
There is an increased risk of injury, possibly
even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reacti-
vate the special seat belt retractor and
secure the child restraint system properly.
The seat belt on the front-passenger's side isequipped with a special seat belt retractor.When activated, the special seat belt retractorensures that the seat belt cannot slacken oncethe child seat is secured.
Installing a child restraint system:
XMake sure you observe the child restraintsystem manufacturer's installation instruc-tions.
XPull the seat belt smoothly out of the beltloop.
XEngage seat belt tongue in belt buckle.
Activating the special seat belt retractor:
XPull the seat belt out fully and let the inertiareel retract it again.While the seat belt is retracting, you shouldhear a ratcheting sound. The special seatbelt retractor is enabled.
XPush the child restraint system down so thatthe seat belt is tight and does not loosen.
54Children in the vehicle
Safety

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)
56Driving safety systems
Safety

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).
Driving safety systems57
Safety
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4 mph (7 km/h). It uses radar sensor technol-ogy to assess the traffic situation.
Up to a speed of approximately 155 mph(250 km/h), Adaptive Brake Assist is capableof reacting to moving objects that havealready been detected as such at least onceover the period of observation.
Up to a speed of approximately 44 mph(70 km/h), Adaptive Brake Assist reacts tostationary obstacles.
If Adaptive Brake Assist demands particularlyhigh braking force, preventative passenger
protection measures (PRE-SAFE®) are activa-ted simultaneously (Ypage 53).
XKeep the brake pedal depressed until theemergency braking situation is over.ABS prevents the wheels from locking.
The brakes will work normally again if:
Ryou release the brake pedal
Rthere is no longer any danger of a collision
Rno obstacle is detected in front of your vehi-cle
Adaptive Brake Assist is then deactivated.
Important safety notes
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist can:
Rintervene unnecessarily
Rnot intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate
the intervention in a non-critical driving sit-
uation.
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen cornering
As a result, the Adaptive Brake Assist may
not intervene in all critical conditions. There
is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
Always adapt your speed to suit the prevail-
ing road and traffic conditions.
Due to the nature of the system, particularlycomplicated but non-critical driving conditionsmay also cause Adaptive Brake Assist to inter-vene.
If Adaptive Brake Assist is not available due toa malfunction in the radar sensor system, thebrake system remains available with full brakeboosting effect and BAS.
Adaptive brake lights
iObserve the "Important safety notes" sec-tion (Ypage 57).
If you brake sharply from a speed of more than50 km/h or if braking is assisted by BAS orBrake Assist with Cross-Traffic Assist, thebrake lamps flash rapidly. In this way, traffictraveling behind you is warned in an evenmore noticeable manner.
If you brake sharply from a speed of more than70 km/h to a standstill, the hazard warninglamps are activated automatically. If thebrakes are applied again, the brake lamps lightup continuously. The hazard warning lampsswitch off automatically if you travel fasterthan 10 km/h. You can also switch off thehazard warning lamps using the hazard warn-ing button (Ypage 99).
ESP®(Electronic Stability Program)
General notes
iObserve the "Important safety notes" sec-tion (Ypage 57).
ESP®monitors driving stability and traction,i.e. power transmission between the tires andthe road surface.
If ESP®detects that the vehicle is deviatingfrom the direction desired by the driver, one ormore wheels are braked to stabilize the vehi-cle. The engine output is also modified to keep
60Driving safety systems
Safety

iActivate ESP®as soon as the situations
described above no longer apply. ESP®willotherwise not be able to stabilize the vehicleif the vehicle starts to skid or a wheel startsto spin.
!Avoid spinning the driven wheels for an
extended period with ESP®deactivated. Youcould otherwise damage the drivetrain.
Deactivating/activating ESP®
XTo activate SPORT handling mode:brieflypress buttonC.ThetSPORT handling mode warninglamp in the instrument cluster lights up. TheSPORT Handling ModeSPORT Handling Modemessage appears inthe multifunction display.
XTo deactivate SPORT handling mode:briefly press buttonC.ThetSPORT handling mode warninglamp in the instrument cluster goes out.
XTo deactivate ESP®:press buttonCuntil
the

ProblemPossible causes/consequences andPPSolutions
The engine cannot bestarted using the Smart-Key.
The on-board voltage is too low.
XSwitch off non-essential consumers, e.g. seat heating or interiorlighting, and try to start the engine again.
If this does not work:
XCheck the starter battery and charge it if necessary(Ypage 259).
or
XJump-start the vehicle (Ypage 260).
or
XConsult a qualified specialist workshop.
The engine cannot bestarted using KEYLESS-GO. The SmartKey is inthe vehicle.
The vehicle is locked.
XUnlock the vehicle and try to start the vehicle again.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 69) and replace it if neces-sary (Ypage 69).
If this does not work:
XStart your vehicle with the SmartKey in the ignition lock.
There is interference from a powerful source of radio waves.
XStart your vehicle with the SmartKey in the ignition lock.
You have lost a Smart-Key.XHave the SmartKey deactivated at a qualified specialist work-shop.
XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
You have lost themechanical key.XReport the loss immediately to the vehicle insurers.
XIf necessary, have the locks changed as well.
The side windows can-not be opened or closedusing the convenienceopening/closing fea-ture.
The SmartKey battery is discharged or nearly discharged.
XCheck the SmartKey battery (Ypage 69) and replace it if neces-sary (Ypage 69).
Doors
Important safety notes
GWARNING
If children are left unsupervised in the vehi-
cle, they could:
Roperate the vehicle's equipment
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake
Rshift the automatic transmission out of
park position]
Rstart the engine
There is a risk of an accident and injury.
Doors71
Opening and closing
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Automatic locking feature
XTo deactivate:press and hold buttonCforabout five seconds until a tone sounds.
XTo activate:press and hold buttonDforabout five seconds until a tone sounds.
If you press one of the two buttons and do nothear a tone, the relevant setting has alreadybeen selected.
The vehicle is locked automatically when theignition is switched on and the wheels areturning.
You could therefore lock yourself out if:
Rthe vehicle is being pushed.
Rthe vehicle is being towed.
Rthe vehicle is on a roller dynamometer.
You can also switch the automatic lockingfunction on and off using the on-board com-puter (Ypage 178).
Unlocking/locking the driver's door
using the mechanical key
iIf you want to centrally lock the vehicleusing the mechanical key, begin by pressingthe locking button for the interior lockingmechanism while the driver's door is open.Then lock the driver's door using themechanical key.
XTo unlock:turn the mechanical key coun-ter-clockwise as far as it will go to positionG.
XTo lock:turn the mechanical key clockwiseas far as it will go to positionG.
If you use the mechanical key to unlock andopen the driver's door, the anti-theft alarmsystem will be triggered. Switch off the alarm(Ypage 64).
Trunk
Important safety notes
GWARNING
If objects, luggage or loads are not secured
or not secured sufficiently, they could slip,
tip over or be flung around and thereby hit
vehicle occupants. There is a risk of injury,
particularly in the event of sudden braking
or a sudden change in direction.
Always store objects so that they cannot be
flung around. Secure objects, luggage or
loads against slipping or tipping before the
journey.
!The trunk lid swings upwards whenopened. Therefore, make sure that there issufficient clearance above the trunk lid.
!Only close the trunk once the roof is low-ered completely. Otherwise, you could dam-age the roof.
If you close the trunk lid before the roof islowered completely, the loading aid switchlights up and a warning tone sounds.
Trunk73
Opening and closing
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