2019 MERCEDES-BENZ C CLASS key battery

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
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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.
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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.
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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.
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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.
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Thevehicle is not unlocked:
RIfyou havelockedthevehicle usingtheSmartKey.
RIfyou havelockedthevehicle using KEY‐LESS-GO.
Locking/unlockingthevehicle with KEY‐LESS-GO
RequirementsRThe SmartKeyis outsidethevehicle.
RThe distance betweenthe SmartKeyandthevehicle does notexceed 3ft(1 m).
RThe driver's door andthe door at whichthedoor handle is used are closed.
Tounlockthevehicle:touchthe inner sur‐face ofthe door handle.
Tolockthevehicle:touch sensor surface1or2.
Convenience closing:touchrecessed sen‐sor surface2untilthe closing procedure iscomplete.
Further information on convenience closing(page82).
Ifyou openthe trunk lid from outside it is auto‐matically unlocked.
Problems with KEYLESS-GO
ProblemPossible causes/consequences andPPSolutions
You can no longer lock or unlockthevehicle using KEYLESS-GO.Possible causes are:
RThe SmartKeyfunctions havebeen deactivated (page 65).
RThe SmartKeybattery is discharged or nearlydischarged.
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ProblemPossible causes/consequences andPPSolutions
RThere is interference from a powerfulradio signal source.
RThe SmartKeyisfaulty.
Activatethe SmartKeyfunctions (page 65).
Checkthe battery usingthe batterycheck lamp andreplace if necessary (page 66).
Usethe emergencykeytounlockor lockthevehicle (page 66).
Havethevehicle and SmartKeychecked at aqualified specialistworkshop.
Activating/deactivating the automatic lock‐ingfeature
Thevehicle is locked automatically whentheignition is switched on andthe wheels are turn‐ingfasterthanwalking pace.
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ProblemPossible causes/consequences andPPSolutions
Make surethat no parts ofthe body are inthe closing area.
Tostopthe closing process,releasethe button or pressthe button againtoreopenthe side win‐dow.
If a side window is obstructed during closing andreopens again slightly:
Immediately afterthe window is blocked, pullthe corresponding switch again untilthe side window hasclosed, and holdthe switchfor an additional second.The side window will be closed with increasedforce.
If a side window is obstructed again during closing andreopens again slightly:
Repeatthe previousstep.The side window is closed withoutthe automaticreversing function.
The side windowscannot be opened orclosed usingthe convenience openingfeature.
The SmartKeybattery is discharged or nearly discharged.
Checkthe battery usingthe batterycheck lamp andreplace if necessary (page 66).
Sliding sunroof
Opening and closingthe sliding sunroof
Theterm"sliding sunroof" alsoreferstothepanoramic sliding sunroof.
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