MERCEDES-BENZ C CLASS 2019 Repair Manual

The seat belts onthefollowing seats are equip‐ped with a special seat beltretractor:
RFront passenger seat
RRear seats
When enabled,the special seat beltretractorensuresthatthe seat belts ofthe frontpassenger seat andrear seats do not slackenoncethechildrestraint system is secured(page54).
Installthechildrestraint system.The entire base ofthechildrestraint systemmust alwaysrestonthe sitting surface oftherear seat.
Always make surethatthe shoulder beltstrap is correctlyrouted fromthe seat beltoutlet ofthevehicletothe shoulder beltguide onthechildrestraint system.The shoulder beltstrap must beroutedfor‐wards and downwards fromthe seat belt out‐let.
Notes onrearward-facing andforward-facingchildrestraint systems onthe frontpassenger seat
\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.
Observethe specific instructionsfortherear‐ward-facing andforward-facingchildrestraintsystems (page 60).
Warning notice onthe front passenger sun visor
Always observethestatus ofthe front passengerfront airbag onthePASSENGER AIRBAG OFFindicator lamp:
RWhen using arearward-facingchildrestraintsystem onthe front passenger seat,the frontpassenger front airbag must always be disa‐bled. This is onlythe case ifthePASSENGERAIRBAG OFF indicator lamp is lit continu‐ously (page44).
RIfthePASSENGER AIRBAG OFF indicatorlamp is off,the front passenger front airbagis enabled. The front passenger front airbagmay deploy during an accident.
Occupant safety59

Securingthechildrestraint system withtheseat belt onthe front passenger seat
When installing a belt-securedchildrestraintsystem onthe front passenger seat, alwaysobservethefollowing:
sObservethechildrestraint system manufac‐turer's installation and operating instruc‐tions.
sWhen using aforward-facingchildrestraintsystem in Group I:removethe headrestraint fromtherespective seat, if possi‐ble.
Whenyouremovethechildrestraint sys‐tem, installthe headrestraint again immedi‐ately and adjust allthe headrestraints cor‐rectly.
sThe backrestoftheforward-facingchildrestraint system must lie asflat as possibleagainstthe backrest ofthe front passengerseat.
sFor certainchildrestraint systems inweightgroup II or III,there may berestrictions inthe maximum size setting, e.g. duetopossi‐ble contact with theroof.
sThechildrestraint system must not be putunderstrain betweentheroof andthe seatcushion and/or be installedfacingthewrong direction.Adjustthe seat backrestinclination accordingly.
sThechildrestraint system must not be putunderstrainbythe headrestraints.Adjustthe headrestraints accordingly.
sNever place objects under or behindthechildrestraint system, e.g. cushions.
The seat belt onthe front passenger side isequipped with a special seatbeltretractor.
When activated,the special seatbeltretractorensuresthatthe seat belt does not slacken oncethechildrestraint system is secured(page54).
Setthe front passenger seat asfar back aspossible and movethe seat intothe highestposition.
Fullyretractthe seat cushion length adjust‐ment.
Adjustthe seat cushion inclination sothatthe front edge ofthe seat cushion is inthe
highest position andtherear edge oftheseat cushion is inthe lowestposition.
Setthe seat backresttoan almostverticalposition.
Installthechildrestraint system.The entire base ofthechildrestraint systemmust alwaysrestonthe seat cushion ofthefront passenger seat.
Always make surethatthe shoulder beltstrap is correctlyrouted fromthe seat beltoutlet ofthevehicletothe shoulder beltguide onthechildrestraint system.The shoulder beltstrap must beroutedfor‐wards and downwards fromthe seat belt out‐let.
If necessary,adjustthe seat belt outlet andthe front passenger seat accordingly.
60Occupant safety

Child safety locks
Activating/deactivating thechild safety lockfor therear doors
\nWARNINGRisk of accident and injuryduetochildren and animals left unatten‐ded inthevehicle
Ifyou leavechildren and animals unattendedinthevehicle,theymay be abletosetthevehicle in motion,forexampleby:
RReleasingthe parking brake.
RShiftingthe automatic transmission outof park position].
RStartingthe engine.
In addition,theymay operatevehicle equip‐ment and become trapped.
Never leavechildren and animals unat‐tended inthevehicle.
When leavingthevehicle, alwaystakethe SmartKeywithyou and lockthevehicle.
\nWARNINGRisk offatal injury duetoexposuretoextreme heat or cold inthevehicle
If people – particularlychildren – areexposedtoextremetemperaturesover anextended period of time,there is arisk ofserious orevenfatal injury.
Never leaveanyone – particularlychil‐dren – unattended inthevehicle.
Never leaveanimals inthevehicle unat‐tended.
\nWARNINGRisk of accident and injuryduetochildren left unattended inthevehicle
Whenchildren are traveling inthevehicle,theycould:
Ropen doors,thereby endangeringotherpeople orroad users
Rgetout ofthevehicle and be hitbytraffic
Roperatevehicle equipment and becometrapped,forexample
Whenchildren are traveling inthevehi‐cle, always activatetheavailablechildsafety locks.
Never leavechildren unattended inthevehicle.
When leavingthevehicle, alwaystakethekey withyou and lockthevehicle.
Child safety locksfortherear doors andtherearside windowsareavailable.Thechild safety lock ontherear doors secureseach door separately.The doors can no longerbe opened fromthe inside.
Occupant safety61

Pressthe lever in direction1(activate) or2(deactivate).
Make surethatthechild safety locksareworking properly.
Activating/deactivating thechild safety lockfor therear side windows
Toactivate/deactivate:press button2.
Therear side windowcan be opened orclosed inthefollowing cases:
Rwith indicator lamp1lit: viathe switchonthe driver's door
Rwith indicator lamp1off: viathe switchonthe correspondingrear door or driv‐er's door
Notes on pets inthevehicle
\nWARNINGRisk of accident and injuryduetoanimals left unsecured or unat‐tended inthevehicle
Ifyou leaveanimals inthevehicle unatten‐ded or unsecured,theycould possiblypressdown buttons or switches.
Thereby an animal may:
Ractivatevehicle equipment and becometrapped,forexample
Rswitchsystems on or off and endangerotherroad users
Unsecured animals may bethrown around inthevehicle intheevent of an accident orsuddensteering and braking maneuver andinjurevehicle occupants inthe process.
62Occupant safety

Never leaveanimals inthevehicle unat‐tended.
Always correctly secureanimals whiledriving,forexample using a suitableanimal carrier.
Occupant safety63

SmartKey
Overview of SmartKeyfunctions
\nWARNINGRisk of accident and injuryduetochildren left unattended inthevehicle
Ifchildren are left unattended inthevehicle,theycould:
ROpen doors,thereby endangeringotherpersons orroad users.
RGet out ofthevehicle and be hitbyoncoming traffic.
ROperate vehicle equipment and becometrapped,forexample.
In addition,children could also setthevehi‐cle in motion,forexample,by:
RReleasingthe parking brake.
RShiftingthe automatic transmission outof park position]or shifting manualtransmission into neutral.
RStartingthe engine
When leavingthevehicle, alwaystakethe SmartKeywithyou and lockthevehicle.
Never leavechildren and animals unat‐tended inthevehicle.
Keepthe SmartKeyout ofreach ofchil‐dren.
NOTEDamagetothekey causedbymagneticfields
Keepthekeyawayfromstrong mag‐neticfields.
1Locks
2Batterycheck lamp
3Unlocks
4Opens/closesthe trunk lid
5Panic alarm
The SmartKey mayvaryfromthe one showninthe diagram, depending onthevehicleequipment.
The SmartKeylocksand unlocksthefollowingcomponents:
Rthe doors
Rthe trunk lid
Rthe fuelfillerflap
64Opening and closing

Ifthevehicle is not opened within approximately40 seconds after unlocking, it locksagain. Anti-theft protection is activated again.
Do notkeepthe SmartKeytogether with elec‐tronic devices or metal objects. This can affectthe SmartKey's functionality.
If batterycheck lamp2does not light upafter pressingthe6or7button,thebattery is discharged.
Replacingthe SmartKeybattery(page 66).
Activating/deactivating the acoustic lockingverification signal
Multimedia system:
VehicleîVehicle SettingsAcoustic Lock
Activatesor deactivateSthe function.
Activating/deactivating the panic alarm
Requirements:RThe ignition is switched off
The panic alarm function is onlyavailable incertain countries.
Toactivate:press button1for approx‐imatelyone second.A visual and audible alarm is triggered.Todeactivate:briefly press button1again.
or
Pressthestart/stop button onthe cockpit(the SmartKeyis insidethevehicle).
Changingthe unlocking settings
Possible unlocking functions ofthe SmartKey:
RCentral unlocking
RUnlockingthe driver's door and fuelfillerflap
Toswitch between settings:pressthe6and7buttons simultaneouslyforapproximately six seconds untilthe batterycheck lampflashes twice.
Ifthe unlocking functionforthe driver's doorand fuelfillerflap has been selected:
RPressingthe6button a second time cen‐trally unlocksthevehicle
RVehicles with KEYLESS-GO:Ifyoutouchthe inner surface ofthe door handle onthedriver's door, onlythe driver's door and fuelfillerflap are unlocked.
Deactivatingthe SmartKeyfunctions
Ifyou do not usethevehicle or a SmartKey foranextended period of time,you canreducetheenergy consumption oftherespective Smart‐Key .Todo so, deactivatethe SmartKeyfunc‐tions.
Opening and closing65

Todeactivate:pressthe7button ontheSmartKeytwice inquick succession.The batterycheck lamp ofthe SmartKeyflashes twice brieflyand lights up once.
Toactivate:press any button onthe Smart‐Key.
Whenthevehicle isstarted withthe Smart‐Key inthestowage compartment ofthe cen‐ter console,the SmartKeyfunctions areautomaticallyactivated (page145).
Removing/inserting the emergencykey
Toremove:pressrelease button1.Emergencykey2is pushed out slightly.
Pull out emergencykey2until it engages inthe intermediate position.
You can usethe intermediate position ofemergencykey2toattachthe SmartKeytoakeyring.
Pressrelease button1again and fullyremoveemergencykey2.
Toinsert:pressrelease button1.
Insert emergencykey2tothe intermediateposition or fully until it engages.
Replacing the SmartKeybattery
\nDANGERSerious damagetohealthcausedbyswallowing batteries
Batteries containtoxic and corrosive sub‐stances. Swallowing batteries may causeserious damagetohealth.
There is arisk offatal injury.
Keep batteries out ofthereach ofchil‐dren.
If batteries are swallowed, seek medicalattention immediately.
ENVIRONMENTALNOTEEnvironmentaldamagecausedbyimproper disposal ofbatteries
Batteries contain pollutants. It isillegaltodispose ofthem withthe householdrubbish.

Dispose of batteries in anenvironmentallyresponsible manner.Takedischarged batteriestoaqualifiedspecialistworkshop ortoa collectionpointfor used batteries.
66Opening and closing

Requirements:RYourequire a CR 2032 3 V cell battery.
Mercedes-Benzrecommendsthatyou havethebatteryreplaced at aqualified specialistwork‐shop.
Removethe emergencykey (page 66).
Pressrelease button2down fully and slidecover1inthe direction ofthe arrow.
Fold out cover1inthe direction ofthearrowandremove.
Removebattery compartment3andtakeoutthe discharged battery.
Insertthe new battery into battery compart‐ment3. Observethe positive pole markinginthe battery compartment and onthe bat‐terywhen doingthis.
Push in battery compartment3.
Re-attach cover1and push it until itengages.
Problems withthe SmartKey
ProblemPossible causes/consequences andPPSolutions
You can no longer lock or unlockthevehicle.Possible causes are:
RThe SmartKeybattery is discharged or nearly discharged.
RThere is interference from a powerfulradio signal source.
Opening and closing67

ProblemPossible causes/consequences andPPSolutions
RThe SmartKeyis defective.
Checkthe battery usingthe batterycheck lamp andreplace if necessary (page 66).
Usethe emergencykeytolock or unlock (page 66).
Havethe SmartKeychecked at aqualified specialistworkshop.
You havelost a SmartKey.Havethe SmartKeydeactivated at aqualified specialistworkshop.
If necessary,havethe mechanical lockchanged aswell.
68Opening and closing