2019 MERCEDES-BENZ GLC warning lights

The seat belt adjustment will apply a certaintightening force if any slack is detected betweenthe vehicle occupant and the seat belt. Do notgrab hold of the seat belt.
You can switch the seat belt adjustment on andoff using the multimedia system. Information onswitching the seat belt adjustment on and offcan be found in the Digital Operating Instruc-tions.
Belt warning for the driver and front
passenger
Thevseat belt warning lamp in the instru-ment cluster is a reminder that all vehicle occu-pants must wear their seat belts. It may light upcontinuously or flash. In addition, there may bea warning tone.
Regardless of whether the driver's seat belt hasalready been fastened, thevseat belt warn-ing lamp lights up for six seconds each time theengine is started. If the front doors are closedand the driver's or front-passenger seat belt hasnot been fastened, thevseat belt warninglamp lights up again after the six seconds. Assoon as the driver's and front-passenger seatbelts are fastened or a front door is openedagain, thevseat belt warning lamp goes out.
If the driver's seat belt is not fastened after theengine is started, an additional warning tone willsound. The warning tone switches off after sixseconds or once the driver's seat belt is fas-tened.
If the vehicle's speed exceeds 15 mph(25 km/h)once and the driver's and front-passenger seat belts are not fastened, a warningtone sounds. A warning tone also sounds withincreasing intensity for 60 seconds or until thedriver or front passenger have fastened theirseat belts.
If the driver or front passenger unfasten theirseat belts during the journey, the seat belt warn-ing is activated again.
Air bags
Introduction
The installation point of an air bag can be rec-ognized by the AIRBAG marking.
An air bag complements the correctly fastenedseat belt. It is no substitute for the seat belt. The
air bag provides additional protection in appli-cable accident situations.
Not all air bags are deployed in an accident. Thedifferent air bag systems function independ-ently from one another (Ypage 55).
However, no system available today can com-pletely eliminate injuries and fatalities.
It is also not possible to rule out a risk of injurycaused by an air bag due to the high speed atwhich the air bag must be deployed.
Important safety notes
GWARNING
If you do not sit in the correct seat position,
the air bag cannot protect as intended and
could even cause additional injury when
deployed. This poses an increased risk of
injury or even fatal injury.
To avoid hazardous situations, always make
sure that all of the vehicle's occupants:
Rhave fastened their seat belts correctly,
including pregnant women
Rare sitting correctly and maintain the great-
est possible distance to the air bags
Rfollow the following instructions
Always make sure that there are no objects
between the air bag and the vehicle's occu-
pants.
RAdjust the seats properly before beginningyour journey. Always make sure that the seatis in an almost upright position. The center ofthe head restraint must support the head atabout eye level.
RMove the driver's and front-passenger seatsas far back as possible. The driver's seat posi-tion must allow the vehicle to be driven safely.
ROnly hold the steering wheel on the outside.This allows the air bag to be fully deployed.
RAlways lean against the backrest while driv-ing. Do not lean forward or lean against thedoor or side window. You may otherwise be inthe deployment area of the air bags.
RAlways keep your feet in the footwell in frontof the seat. Do not put your feet on the dash-
48Occupant safety
Safety

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 237). 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-
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 54).
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 and
52Occupant safety
Safety

remains 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 seatas 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 59).
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-
Occupant safety53
Safety
Z

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.
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 51). 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 54).
Problems with the Occupant Classification System (OCS)
Be sure to observe the notes on "System self-test" (Ypage 53).
54Occupant safety
Safety

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 51).
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
Occupant safety55
Safety
Z

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.
An electric motor is used by PRE-SAFE®to trig-ger the tightening of the seat belt in hazardoussituations. 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 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 44)
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 and driver's knee bag
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 44).
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-sive role in the deployment of an air bag. Nor do
56Occupant safety
Safety

Driving safety systems
Overview of driving safety systems
In this section, you will find information aboutthe following driving safety systems:
RABS (Anti-lockBrakingSystem)(Ypage 65)
RBAS (BrakeAssistSystem) (Ypage 66)
RActive Brake Assist (Ypage 66)
RESP®(ElectronicStabilityProgram)(Ypage 68)
REBD (ElectronicBrake forceDistribution)(Ypage 72)
RADAPTIVE BRAKE (Ypage 72)
RActive Brake Assist with cross-traffic function(Ypage 72)
RSTEER CONTROL (Ypage 75)
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 areresponsible for maintaining the distance to thevehicle in front, for vehicle speed, for braking ingood time, and for staying in lane. Always adaptyour driving style to suit the prevailing road andweather conditions and maintain a safe distancefrom 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. Pay particular attention to the informa-tion regarding tires, recommended minimumtire tread depths etc. in the "Wheels and tires"section (Ypage 330).
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 65).
GWARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid-
ding 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 259) and dis-play messages which may be shown in theinstrument cluster (Ypage 228).
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.
Driving safety systems65
Safety
Z

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.
HEnvironmental note
Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment.
Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
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 thebatteries 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 80).
If the SmartKey battery is checked within thesignal reception range of the vehicle, pressingthe7or6button:
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 79).
XPress mechanical keyDinto the SmartKeyopening in the direction of the arrow until bat-tery compartment coverCopens. Do nothold battery compartment coverCclosedwhile doing so.
XRemove battery compartment coverC.
80SmartKey
Opening and closing