MERCEDES-BENZ C CLASS 2019 Service Manual

Vehicles with automatic front passengerfront airbag shutoff:
NOTEDeployment ofthe EmergencyTensioning Device and side air bag whenthe front passenger seat is unoccupied
Ifthe seat belttongue is engaged inthe seatbelt buckle ofthe unoccupied frontpassenger seat,the EmergencyTensioningDevice andthe side air bag may also deployintheevent of an accident along withothersystems.
Only one person should use each seatbelt at any one time.
Vehicles without automatic front passengerfront airbag shutoff:
NOTEDeployment ofthe EmergencyTensioning Device whenthe front-passenger seat is unoccupied
Ifthe seat belttongue is engaged inthe seatbelt buckle ofthe unoccupied front-passenger seat,the EmergencyTensioning
Device may also deployintheevent of anaccident along withother systems.
Only one person should use each seatbelt at any one time.
Seat belt adjustment function
Vehicles with PRE-SAFE®:Ifthe front seat beltis not pulled tight acrossyour body,the seat beltadjustment may automatically apply a certaintighteningforce. Do not holdthe seat belt tightlywhile it is adjusting.
You can activate and deactivatethe seat beltadjustment function usingthe multimedia sys‐tem (page 39).
Releasing seat belts
Presstherelease button inthe seat beltbuckle and guidethe seat belt back withtheseat belttongue.
Activating/deactivating seat belt adjustmentvia the multimedia system
Multimedia system:
VehicleîVehicle SettingsBelt Adjustment
Activatesor deactivateSthe function.
Seat beltwarning functionfor the driver andfront passenger
The

Inthefollowing cases,the seat beltwarninglights up during a journey if:
RThevehicle speedexceeds15mph(25 km/h) andthe driver's or frontpassenger seat belt is notfastened.
RThe driver or front passenger unfastenstheirseat belt whilethevehicle is in motion.
Airbags
Overview of airbags
1Knee airbag
2Driver's airbag
3Front passenger front airbag
4Window curtain airbag
5Side airbag
The installation location of an airbag is identifiedbythe AIRBAGsymbol.
When activated, an airbag can provide additionalprotectionfortherespectivevehicle occupant.
Potential protection from each airbag:
AirbagPotential protectionfor…
Knee airbag Thigh, knee and lower leg
Driver's airbag,front passengerfront airbag
Head andribcage
Window curtainairbagHead
Side airbag Ribcage, also pelvisforfront seat occupants
The front passenger front airbag can only bedeployed in an accident ifthePASSENGER AIR
BAG OFF indicator lamp is off. Ifthe frontpassenger seat is occupied, make sure, bothbefore and duringthe journey,thatthestatus ofthe front passenger front airbag is correct(page44).
NOTEImportant pointstoremember ifthe front passenger seat is unoccupied
In an accident,the components oftherestraint system may deploy unnecessarilyonthe front passenger side if:
RThere are heavy objects onthe frontpassenger seat.
RThe seat belttongue is engaged intheseat belt buckle ofthe front passengerseat andthe front passenger seat isunoccupied.
Stowobjects in a suitable place.
Only one person should use each seatbelt at any one time.
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Protectionbythe airbags
Depending onthe accident situation, an airbagmay supplementthe protection offeredbya cor‐rectlyfastened seat belt.
\nWARNINGRisk of injuryor death duetoincorrect seat position
Ifyou deviate fromthe correct seat position,the air bag cannotperformits intended pro‐tective function and deployment mayevencause further injuries.
Toavoid hazardous situations, always makesurethat allvehicle occupants:
RHavetheir seat beltfastened correctly,including pregnantwomen.
RAre seated properly andthat distancetothe air bags is as large as possible.
RObservethefollowing information.
Always make surethatthere are noobjects betweenthe air bag andthevehicle occupant.
Toavoidtherisksresulting fromthe deploymentof an airbag, eachvehicle occupant mustobservethefollowing information:
RBeforestartingyour journey,adjustyour seatcorrectly;the driver's seat and front-passenger seat should be moved asfar backas possible.
When doing so, always observethe informa‐tion onthe correct driver's seat position(page90).
ROnly holdthesteering wheelbythesteeringwheelrim. This allowsthe airbagtobe fullydeployed.
RAlways lean againstthe seat backrest whenthevehicle is in motion. Do not leanforwardsor againstthe door or side window.You mayotherwise be inthe deployment area oftheairbags.
RAlwayskeepyourfeetonthefloor. Do notputyourfeetonthe cockpit,forexample.Yourfeetmayotherwise be inthe deploy‐ment area ofthe airbag.
RIfchildren are traveling inthevehicle,observethe additional notes(page 49).
RAlwaysstowand secure objects correctly.
Objects inthevehicle interior may prevent anairbag from functioning correctly.Eachvehicleoccupant must always make sure ofthefollow‐ing:
RThere are no people, animals or objectsbetweenthevehicle occupants and an air‐bag.
RThere are no objects betweenthe seat, doorand door pillar (B-pillar).
RThere are no hard objects, e.g. coat hangers,hanging onthe grab handles or coat hooks.
RThere are no accessory parts, such as PNDs(PersonalNavigation Devices), mobilephones or cup holders attachedtothevehi‐cle withinthe deployment area of an airbag,e.g. onthe cockpit, on doors, side windowsor side paneling.
In addition, no connecting cable,tensioningstrap orretainingstrap may berouted
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through or attached inthe deployment areaof an airbag. Always observethe accessorymanufacturer's installation instructions, inparticularthe information on suitable placesfor installation.
RThere are no heavy, sharp-edged or fragileobjects inthe pockets ofyour clothing.Storesuch objects in a suitable place.
Limited protection from airbags
\nWARNINGRisk of injuryduetomodifi‐cationstothe airbag cover
Ifyou modifythe cover of an airbag or affixobjects such asstickerstoit,the airbag mayno longer function correctly.
Never modifythe cover of an airbag anddo not affix objectstoit.
The installation location of an airbag is identifiedbythe AIRBAGsymbol (page 40).
\nWARNINGRisk of injuryor death duetothe use of unsuitable seat covers
Unsuitable seat coverscan obstruct or pre‐ventthe deployment of air bags integratedintothe seats.
Consequently,the air bags cannotprotectvehicle occupants astheyare designedtodo. In addition, operation ofthe automaticfront passenger air bag shutoff may berestricted.
You should onlyuse seat coversthathavebeen approvedforthe correspond‐ing seatsbyMercedes-Benz.
\nWARNINGRisk of injuryduetomalfunc‐tions ofthe sensors inthe door paneling
Sensorstocontrolthe airbags are located inthe doors. Modifications orworknot per‐formed correctlytothe doors or door panel‐ing, aswell as damaged doors, can leadtothe function ofthe sensors being impaired.The airbags mighttherefore not functionproperlyany more.
Consequently,the airbags cannotprotectvehicle occupants astheyare designedtodo.
Never modifythe doors or parts ofthedoors.
Always haveworkonthe doors or doorpaneling carried out at aqualified spe‐cialistworkshop.
\nWARNINGRisk of injuryduetodeployedairbag
A deployed airbag no longer has a protectivefunction and cannotprotect as intended intheevent of an accident.
Havethevehicletowedtoaqualifiedspecialistworkshop in ordertohavethedeployed airbagreplaced.
Havedeployed airbagsreplaced immediately.
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Status ofthe front passenger front airbag
Function ofthe automatic front passengerfront airbag shutoffThe automatic front passenger front airbag shut‐off is abletodetect whetherthe front passengerseat is occupiedbya person or achildrestraintsystem. The front passenger front airbag is ena‐bled or disabled accordingly.
When installing achildrestraint system onthefront passenger seat, always make sure ofthefollowing:
REnsurethatthechildrestraint system is posi‐tioned correctly (page48).
RAlways observethechildrestraint systemmanufacturer's installation instructions.
RNever place objects, e.g. cushions, under orbehindthechildrestraint system.
RFullyretractthe seat cushion length adjust‐ment.
RThe entire base ofthechildrestraint systemmust alwaysrestonthe seat cushion ofthefront passenger seat.
RThe backrest oftheforward-facingchildrestraint system must lie asflat as possibleagainstthe backrest ofthe front passengerseat.
RThechildrestraint system must nottouchtheroof or be put understrainbythe headrestraints.Adjustthe seat backrest inclina‐tion andthe headrestraint setting accord‐ingly.
\nWARNINGRisk of injuryor death duetoobjects betweenthe sitting surface andthechildrestraint system
Objects betweenthe sitting surface andthechildrestraint system could affectthe func‐tion ofthe automatic front passenger airbagshutoff.
This couldresult inthe front passenger air‐bag not functioning as intended during anaccident.
Do not place any objects betweenthesitting surface andthechildrestraintsystem.
The entire base ofthechildrestraintsystem must alwaysrestonthe sittingsurface ofthe front passenger seat.
The backrest oftheforward-facingchildrestraint system must, asfar as possi‐ble, beresting onthe seat backrest ofthe front passenger seat.
Always comply withthechildrestraintsystem manufacturer's installationinstructions.
A person onthe front passenger seat mustobservethefollowing information:
RFasten seat belts correctly (page36).
RSit in an almost upright seat position withtheir back againstthe seat backrest.
RSit withtheirfeetresting onthefloor, if pos‐sible.
The front passenger front airbag mayotherwisebe disabledbymistake,forexample inthefol‐lowing situations:
RThe front passenger transferstheirweightbysupportingthemselves on avehicle armrest.
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RThe front passenger sits in such awaythattheirweight israised fromthe sitting sur‐face.
\nWARNINGRisk of injuryor death duetodeactivated front passenger airbag
IfthePASSENGER AIRBAG OFF indicatorlamp is lit,the front passenger airbag is disa‐bled. It will not be deployed intheevent ofan accident and cannotperformits intendedprotective function.
A person inthe front passenger seat couldthen,forexample, come into contact withthevehicle interior, especially ifthe person issittingtoo closetothe cockpit.
Ifthe front passenger seat is occupied,always ensurethat:
RThe classification ofthe person inthefront passenger seat is correct andthefront passenger airbag is enabled or disa‐bled in accordance withthe person inthefront passenger seat.
RThe front passenger seat has been movedasfar back as possible.
RThe person is seated correctly.
Ensure, bothbefore and duringthe jour‐ney,thatthestatus ofthe frontpassenger airbag is correct.
Ifthe front passenger seat is occupied,the clas‐sification ofthe person orchildrestraint systemonthe front passenger seattakes place afterthefront passenger front airbag shutoff self-test.ThePASSENGER AIRBAG indicator lamps dis‐playthestatus ofthe front passenger front air‐bag.
Always observethe notes onthe function ofthePASSENGER AIRBAG indicator lamps(page44).
Function ofthePASSENGER AIRBAG indica‐tor lamps
Self-testof automatic front passenger frontairbag shutoffWhenthe ignition is switched on, a self-test isperformed during whichthe twoPASSENGERAIRBAG ON and OFF indicator lamps light upsimultaneously.
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Thestatus ofthe front passenger front airbag isdisplayed afterthe self-test:
RPASSENGER AIRBAG ON lights upfor60 seconds, subsequently bothindicatorlamps are off (PASSENGER AIRBAG ON andOFF):the front passenger front airbag is abletodeploy intheevent of an accident.
RPASSENGER AIRBAG OFF lights up continu‐ously:the front passenger front airbag is dis‐abled. It willthen not be deployed intheevent of an accident.
IfthePASSENGER AIRBAG ON indicator lamp isoff, onlythePASSENGER AIRBAG OFF indicatorlamp shows thestatus ofthe front passengerfront airbag. ThePASSENGER AIRBAG OFF indi‐cator lamp may be lit continuously or be off.
IfthePASSENGER AIRBAG OFF indicator lampandtheurestraint systemwarning lamplight up simultaneously,the front passenger seatmay not be used. Also inthis case, do not installachildrestraint system onthe front passengerseat. Haveautomatic front passenger front air‐bag shutoffchecked andrepaired immediately ataqualified specialistworkshop.
Status displayIfthe front passenger seat is occupied, ensure,bothbefore and duringthe journey,thatthesta‐tus ofthe front passenger front airbag is correctforthe current situation.
After installing arearward-facingchildrestraint system onthe front passengerseat:PASSENGER AIRBAG OFF must be lit con‐tinuously.
\nWARNINGRisk of injuryor death fromusing arearward-facingchildrestraintsystem whenthe front passenger frontairbag is enabled
Ifyou secure achild in arearward-facingchildrestraint system onthe front passengerseat andthePASSENGER AIRBAG OFF indi‐cator lamp is off,the front passenger airbagcan deploy intheevent of an accident.
Thechild could bestruckbythe airbag.
Always ensurethatthe front passenger air‐bag is deactivated. ThePASSENGER AIRBAGOFF indicator lamp must be lit.
NEVER use arearward-facingchildrestraintsystem on a seat protectedbyan ENABLEDFRONT AIRBAGin front of it, DEATH or SERI‐OUS INJURYtotheCHILD can occur.
When installing achildrestraint system onthefront passenger seat, observethevehicle-spe‐cific information (page 59).
Depending onthechildrestraint system andthestature ofthechild,thePASSENGER AIRBAGOFF indicator lamp may be off. Inthis case, donot installtherearward-facingchildrestraintsystem onthe front passenger seat.
Instead, installtherearward-facingchildrestraint system on a suitablerear seat.
After installing aforward-facingchildrestraint system onthe front passengerseat:depending onthechildrestraint systemandthestature ofthechild,PASSENGER AIRBAG OFF may be lit continuously or be off.Always observethefollowing information.
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\nWARNINGRisk of injuryor death duetoincorrect positioning oftheforward-facingchildrestraint system
Ifyou secure achild in aforward-facingchildrestraint system onthe front passenger seatandyou positionthe front passenger seattooclosetothe cockpit, intheevent of an acci‐dent,thechild could:
RCome into contact with thevehicle inte‐rior ifthePASSENGER AIRBAG OFF indi‐cator lamp is lit,forexample.
RBestruckbythe air bag ifthePASSENGER AIRBAG OFF indicator lampis off.
Always movethe front passenger seatasfar back as possible and fullyretractthe seat cushion length adjustment.Always make surethatthe shoulder beltstrap is correctlyrouted fromthe seatbelt outlet onthevehicletothe shoul‐der belt guide onthechildrestraint sys‐tem. The shoulder beltstrap must beroutedforwards and downwards fromthevehicle belt outlet. If necessary,
adjustthe seat belt outlet andthe frontpassenger seat accordingly.
Always observethechildrestraint sys‐tem manufacturer's installation instruc‐tions.
When installing achildrestraint system onthefront passenger seat, observethevehicle-spe‐cific information (page 59).
If a person is sitting onthe front passengerseat:PASSENGER AIRBAG OFF may be lit con‐tinuously or be off, depending onthe person'sstature.
A person onthe front passenger seat mustalways observethefollowing information:
RIfthe front passenger seat is occupiedbyanadult or a person with astature correspond‐ingtothat of an adult,thePASSENGER AIRBAG OFF indicator lamp must be off. Thisindicatesthatthe front passenger front air‐bag is enabled.
IfthePASSENGER AIRBAG OFF indicatorlamp is lit continuously,an adult or person
with a build correspondingtothat of an adultshould not usethe front passenger seat.
Instead,theyshould use arear seat.
RIfthe front passenger seat is occupiedby aperson of smallerstature (e.g. ateenager orsmall adult),thePASSENGER AIRBAG OFFindicator lamp either lights up continuouslyorremains off, depending ontheresult oftheclassification.
-IfthePASSENGER AIRBAG OFF indicatorlamp is off: movethe front passengerseat asfar back as possible, orthe per‐son of smallerstature should use arearseat.
-IfthePASSENGER AIRBAG OFF indicatorlamp is lit continuously:the person ofsmallerstature should not usethe frontpassenger seat.
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\nWARNINGRisk of injuryor death whenthePASSENGER AIRBAG OFF indicatorlamp is lit
IfthePASSENGER AIRBAG OFF indicatorlampremains lit afterthe system self-test,the front passenger air bag is deactivated. Itwill not be deployed intheevent of an acci‐dent. Inthis case,the front passenger air bagcannotperformits intended protective func‐tion, e.g. when a person is seated inthe frontpassenger seat.
That person could,forexample, come intocontact with thevehicle interior, especially ifthe person is sittingtoo closetothe cockpit.
Ifthe front passenger seat is occupied,always ensurethat:
RThe classification ofthe person inthefront passenger seat is correct andthefront passenger air bag is enabled ordeactivated in accordance withthe per‐son inthe front passenger seat.
RThe person is seated properlywith a cor‐rectlyfastened seat belt.
RThe front passenger seat has been movedasfar back as possible.
Be suretoalso observethefollowing furtherrelated subjects:
RChildrestraint system onthe front passengerseat (page 59).
PRE-SAFE®system
PRE-SAFE®(anticipatoryoccupant protec‐tion)
PRE-SAFE®is abletodetect certain critical driv‐ing situations and implement pre-emptive meas‐urestoprotectthevehicle occupants.
PRE-SAFE®can implementthefollowing meas‐ures independently of eachother:
RTighteningthe seat belts onthe driver's seatand front passenger seat.
RClosingthe side windows.
RVehicles with sliding sunroof:Closingthesliding sunroof.
RVehicles with memory function:Movingthe front passenger seattoa morefavorableseat position.
RVehicles with multicontour seat:Increas‐ingthe air pressure inthe seat side bolstersofthe seat backrest.
RPRE-SAFE®Sound: providedthatthe multi‐media system is switched on,generates abrief noise signaltostimulatethe innate pro‐tective mechanism of a person's hearing.
NOTEDamagecausedbyobjects inthefootwell or behindthe seat
The automatic adjustment ofthe seat posi‐tion mayresult in damagetothe seat and/orthe object.
Stowobjects in a suitable place.
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Reversingthe PRE-SAFE®system measures
If an accident did not occur,the pre-emptivemeasuresthatweretaken arereversed.
You will needtoperformcertain settingsyour‐self.
Ifthe seat belt pre-tensioning is notreduced,movethe seat backrest back slightly.The locking mechanismreleases.
Function of PRE-SAFE®PLUS (anticipatoryoccupant protection plus)
PRE-SAFE®PLUS can detect certain impacts,particularlyan imminentrear impact, andtakepre-emptive measurestoprotectthevehicleoccupants. These measures cannot necessarilyprevent an imminent impact.
PRE-SAFE®PLUS can implementthefollowingmeasures independently of eachother:
RTighteningthe seat belts onthe driver's seatand front passenger seat.
RIncreasing brake pressure whenthevehicleisstationary.This brake application is can‐
celed automatically whenthevehicle pullsaway.
If an accident did not occur,the pre-emptivemeasuresthatweretaken arereversed.
System limitations
The system will not initiate any action inthefol‐lowing situations:
Rwhen backing up
The system will not initiate any braking applica‐tion inthefollowing situations:
Rwhilst driving
or
Rwhen entering orexiting a parking spacewhile usingActiveParking Assist
Safely transportingchildren inthevehicle
Always observewhenchildren are travelinginthevehicle
Alsostrictly observethe safety notesforthespecific situation. Inthiswayyou canrecog‐nize potentialrisks andavoid dangers ifchil‐
dren are traveling inthevehicle(page 49).
Be diligentBear in mindthat neglectingtosecure achild inthechildrestraint system may haveserious con‐sequences. Always be diligent in securing achildcarefully beforeevery journey.
Toimprove protectionforchildrenyoungerthan12years old or under 5ft(1.50 m) in height,Mercedes-Benzrecommendsyou observethefollowing information:
RAlways securethechild in achildrestraintsystem suitableforthis Mercedes-Benzvehi‐cle.
RThechildrestraint system must be appropri‐atetothe age,weight and size ofthechild.
RThevehicle seat must be suitablefor instal‐ling achildrestraint system.
Accidentstatistics showthatchildren secured intherear seats aregenerallysaferthanchildrensecured inthe front seats.Forthisreason,Mercedes-Benzstrongly advisesthatyou installachildrestraint system on arear seat.
48Occupant safety