maintenance MERCEDES-BENZ C CLASS 2019 User Guide

Tomake an emergency call:press SOSbutton cover2brieflytoopen.
Press and hold SOS button3for at leastone second.
If a service call is active, an emergency call canstill be triggered. This has priorityover allotheractive calls.
Service calls are only possible if a mobile phonenetwork isavailable.
Information aboutthe service call usingthemebuttonA calltothe Mercedes-Benz Customer Centerhas been initiated viathe me button intheover‐head control panel orthe multimedia system.
Intheevent of a breakdown,you willget sup‐port:
RAqualified Mercedes-Benztechnician pro‐vides breakdown assistance on site and/orthevehicle will betowedtothe nearestauthorized Mercedes-Benz Center.
You may bechargedforthese services.
You canfind information onthefollowingtopics:
RActivation of Mercedes me connect
ROperatingthevehicle
RNearest authorized Mercedes-Benz Center
ROther products and services from Mercedes-Benz
Data is transferred duringthe connectiontotheMercedes-Benz Customer Center(page 321).
Information on Mercedes me connect acci‐dent managementThe Mercedes me connect accident manage‐ment is anextension ofthe Mercedes-Benzemergency call system (page 321).
An emergency call is madetothe Mercedes-Benz emergency call center after an accident:
RAvoice connection is madetoa contact per‐son atthe Mercedes-Benz emergency callcenter.
RIf necessary,the contact person attheMercedes-Benz emergency call centerfor‐
wardsthe calltoMercedes me connect acci‐dent management.
Forwardingthe call is not possible in allcountries.
RIf necessary,thevehicle will betowedtoanauthorized Mercedes-Benz Center.
Arranging a service appointment viaMercedes me connectIfyou haveactivatedthe maintenance manage‐ment service,relevantvehicle data is transferredautomaticallytothe Mercedes-Benz CustomerCenter.You willthenreceiveindividualrecom‐mendationsregardingthe maintenance ofyourvehicle.
Regardless of whetheryou haveconsentedtothe maintenance management service,the multi‐media systemremindsyou after a certainamount of timethat a service is due. A promptappears asking ifyouwould liketomake anappointment.
Toarrange a service appointment:selectCall.Afteryour agreementthevehicle data is sentand a Mercedes-Benz Customer Center
320Multimedia system

ASSYST PLUS service interval display
Function ofthe ASSYST PLUS service intervaldisplay
The ASSYST PLUS service interval display ontheInstrument Display provides information ontheremaining time or distance beforethe nextservice due date.
You can hidethis service message usingtheback button onthe left-hand side ofthesteeringwheel.
Depending on howthevehicle is used,theASSYST PLUS service interval display mayshortenthe service interval, e.g. inthefollowingcases:
RMainly short-distance driving
RWhenthe engine is often leftidlingfor longperiods
RIntheevent of frequent coldstart phases
Mercedes-Benzrecommendsavoiding suchoperating conditions.
You can obtain further information concerningthe servicing ofyourvehicle from aqualified
specialistworkshop, e.g. an authorizedMercedes-Benz Center.
Displayingthe service due date
On-board computer:
ServiceASSYST PLUS
The next service due date is displayed.
Toexitthe display:pressthe back buttononthe left-hand side ofthesteering wheel.
Make suretoobservethefollowing furtherrela‐ted subject:
ROperatingthe on-board computer(page 228).
Information onregular maintenancework
NOTEPrematurewearthroughfailuretoobserveservice due dates
Serviceworkwhich is not carried out attheright time or incompletelycan leadtoincreasedwear and damagetothevehicle.
Always observethe prescribed serviceintervals.
Always havethe prescribed serviceworkcarried out at aqualified specialistworkshop.
Special servicerequirements
The prescribed service interval is based on nor‐mal operation ofthevehicle. Maintenanceworkwill needtobe performed more often ifthevehi‐cle is operated under arduous conditions orincreased loads.
The ASSYST PLUS service interval display is onlyan aid. The driver ofthevehicle bearsresponsi‐bility asregardstowhether maintenanceworkneedstobe performed more oftenthan speci‐fied based onthe actual operating conditionsand/or loads.
Examples of arduous operating conditions:
Rregular city driving with frequent intermedi‐atestops
Rmainly short-distance driving
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Rfrequent operation in mountainousterrain oron poorroad surfaces
Rwhenthe engine is often leftidlingfor longperiods
Roperation in particularly dusty conditionsand/or if air-recirculation mode is frequentlyused
Inthese or similar operating conditions, havetheinterior airfilter, engine air cleaner, engine oiland oilfilteretc.changed more frequently. Thetires must bechecked more frequently ifthevehicle is operated under increased loads.Fur‐ther information can be obtained at aqualifiedspecialistworkshop.
Battery disconnection periods
The ASSYST PLUS service interval displaycan only calculatethe service due datewhenthe batteryis connected.
Notedownthe service due date displayed onthe instrument display before disconnectingthe battery (page 351).
Engine compartment
Opening/closingthe hood
\nWARNINGRisk of accident ifthe enginehood is unlatched while driving
An unlocked engine hood may open up whenthevehicle is in motion and blockyour view.
Never unlatchthe engine hood whiledriving.
Beforeevery trip, ensurethattheengine hood is latched.
\nWARNINGRisk of accident and injurywhen opening and closingthe enginehood
When opening or closingthe engine hood, itmay suddenly drop intothe end position.
There is arisk of injuryfor anyone intheengine hood'srange of movement.
Only open or closethe engine hoodwhenthere are no persons intheengine hood'srange of movement.
\nWARNINGDanger of burns when open‐ingthe hood
Ifyou openthe hood whenthe engine hasoverheated or during afireinthe enginecompartment,you could come into contactwith hotgases orother escaping operatingfluids.
Before openingthe hood, allowtheenginetocool down.
Intheevent of afireinthe engine com‐partment,keepthe hood closed andcallthefireservice.
\nWARNINGRisk of injuryduetomovingparts
Certain components inthe engine compart‐ment may continuetomoveor suddenlymoveagaineven afterthe ignition has beenswitched off, e.g.the coolerfan.
Makesure ofthefollowing before performingtasks inthe engine compartment:
Switchthe ignition off.
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Nevertouchthe danger zone surround‐ing moving component parts, e.g.therotation area ofthefan.
Removejewelry andwatches.
Keep items of clothing and hairawayfrom moving parts.
\nWARNINGRisk of injuryfromtouchingcomponent parts undervoltage
The ignition system andthe fuel injectionsystemworkunder highvoltage. Ifyoutouchcomponent parts which are undervoltage,you couldreceivean electric shock.
Nevertouch component parts oftheignition system orthe fuel injection sys‐tem whenthe ignition is switched on.
\nWARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain components inthe engine compart‐ment can beveryhot, e.g.the engine,theradiator and parts oftheexhaust system.
Allowthe enginetocool down and onlytouch component parts described inthefollowing.
\nWARNINGRisk of injuryfrom usingthewindshield wipers whilethe engine hoodis open
Whenthe engine hood is open andthe wind‐shield wipers are set in motion,you can betrappedbythe wiper linkage.
Always switch offthe windshield wipersand ignition before openingthe enginehood.
Toopen:pull lever1toreleasethe hood.
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Push handle1ofthe hood catch upwardsand liftthe hoodbyapproximately15in(40 cm).Toclose:lowerthe hood and let itfall from aheight of approximately 8 in (20 cm).
Ifthe hood canstill be lifted slightly,openthe hood again and close it with a little moreforce until it engages correctly.
Engine oil
Checkingthe engine oil level usingthe oildipstick
\nWARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain components inthe engine compart‐ment can beveryhot, e.g.the engine,theradiator and parts oftheexhaust system.
Allowthe enginetocool down and onlytouch component parts described inthefollowing.
Requirements:RThe engine must havean oil dipstick.If not,the engine oil level can bechecked only withthe on-board computer (page 355).
Depending onthe engine,the oil dipstick may beinstalled inthe engine compartment in differentlocations.
Thewaiting time beforecheckingthe oil levelwhenthe engine is at normal operatingtempera‐ture isfiveminutes.
Parkthevehicle on a level surface.
Pull oil dipstick1out and wipe off.
Slowly slide oil dipstick1intothe guidetubetothestop, andtakeit out again afterapproximatelythree seconds.ROil level is correct: oil level is between2and3.
ROil leveltoo low: oil level is at3orbelow.
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ROil leveltoo high: oil level is above2.
Ifthe oil level istoo low,add1.1 US qt(1 liter) of engine oil.
Ifthe oil level istoo high, drain offexcessengine oil. Consult aqualified specialistworkshop.
Checkingthe engine oil level usingthe on-board computer
RequirementsThe engine must havean oil level sensor. If not,the engine oil level can bechecked only withtheoil dipstick (page 354).
The engine oil level is determined during driving.Determiningthe engine oil level cantakeupto30 minutes with a normal drivingstyle andevenlonger with an active drivingstyle.
In ordertoreceivearesult asquickly as possi‐ble:
RWarmupthe engine
RParkthevehicle on a level surface
RLeavethe enginerunning at idling speed
On-board computer:
ServiceEngine Oil Level
You will see one ofthefollowing messages onthe multifunction display:
RMeasuring Engine Oil Level...: measurementofthe oil level is notyet possible.
Repeattherequest after a maximum of30 minutes driving.
REngine Oil Level OKandthe bar displayforindicatingthe oil level onthe multifunctiondisplay is green and is between "min" and"max":the oil level is correct.
REngine Oil Level Add 1.0 landthe bar displayfor indicatingthe oil level onthe multifunc‐tion display is orange and is below "min":
Add1.1 US qt (1 l) engine oil.
RReduce Engine Oil Levelandthe bar displayfor indicatingthe oil level onthe multifunc‐tion display is orange and is above"max":
Drain offexcess engine oilthat has beenadded. Consult aqualified specialistwork‐shop.
RFor Engine Oil Level Switch Ignition On:
Switch onthe ignitiontocheckthe engine oillevel.
REngine Oil Level System Inoperative: sensorfaulty or not inserted.
Consult aqualified specialistworkshop.
REngine Oil Level System Currently Unavail.:
Closethe hood.
Adding engine oil
\nWARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain components inthe engine compart‐ment can beveryhot, e.g.the engine,theradiator and parts oftheexhaust system.
Allowthe enginetocool down and onlytouch component parts described inthefollowing.
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\nWARNINGRisk offireand injury fromengine oil
If engine oil comes into contact withhotcomponent parts inthe engine compart‐ment, it may ignite.
Make surethat no engine oil is spillednexttothefiller opening.
Allowthe enginetocool off andthor‐oughly cleanthe engine oil from compo‐nent parts beforestartingthevehicle.
NOTEEngine damagecausedbyanincorrect oilfilter, incorrect oil or addi‐tives
Do not use engine oils or oilfilterswhich do not correspondtothe specifi‐cationsexplicitly prescribedfortheservice intervals.
Do not alterthe engine oil or oilfilter inordertoachievelongerchange intervalsthan prescribed.
Do not use additives.
Followthe instructions inthe serviceinterval displayregardingthe oilchange.
NOTEDamagecausedbyaddingtoomuch engine oil
Too much engine oil can damagethe engineorthe catalytic converter.
Haveexcess engine oilremoved at aqualified specialistworkshop.
Turncap1counter-clockwise andremoveit.
Add engine oil.
Replace cap1and turn it clockwise asfaras it will go.
Checkthe oil level again (page 354).
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Checking coolant level
\nWARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain components inthe engine compart‐ment can beveryhot, e.g.the engine,theradiator and parts oftheexhaust system.
Allowthe enginetocool down and onlytouch component parts described inthefollowing.
\nWARNINGDanger of burns when open‐ingthe hood
Ifyou openthe hood whenthe engine hasoverheated or during afireinthe enginecompartment,you could come into contactwith hotgases orother escaping operatingfluids.
Before openingthe hood, allowtheenginetocool down.
Intheevent of afireinthe engine com‐partment,keepthe hood closed andcallthefireservice.
\nWARNINGRisk of scalding from hotcoolant
The engine cooling system is pressurized,particularly whenthe engine iswarm. Ifyouopenthe cap,you could be scaldedbyhotcoolant spraying out.
Letthe engine cool down before open‐ingthe cap.
When openingthe cap,wear protectivegloves and safetyglasses.
Openthe cap slowlytorelease pres‐sure.
Parkthevehicle on a level surface.
Checkthe coolanttemperature display intheinstrument cluster.The coolanttemperature must be below158 °F (70 °C).
Slowly turn cap1counter-clockwisetorelieve overpressure.
Maintenance and care357

Continue turning cap1counter-clockwiseandremoveit.
The coolant level is correct:
RIfthe engine is cold, uptomarker bar2
RIfthe engine iswarm, upto0.6 in (1.5 cm)over marker bar2
If necessary,add coolantthat has beenapprovedbyMercedes-Benz.RFurther information on coolant(page 429).
Addingwasher fluidtothe windshieldwasher system
\nWARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain components inthe engine compart‐ment can beveryhot, e.g.the engine,theradiator and parts oftheexhaust system.
Allowthe enginetocool down and onlytouch component parts described inthefollowing.
\nWARNINGDanger of burns when open‐ingthe hood
Ifyou openthe hood whenthe engine hasoverheated or during afireinthe enginecompartment,you could come into contactwith hotgases orother escaping operatingfluids.
Before openingthe hood, allowtheenginetocool down.
Intheevent of afireinthe engine com‐partment,keepthe hood closed andcallthefireservice.
\nWARNING‑ Risk offireand injury fromwindshieldwasher concentrate
Windshieldwasher concentrate is highlyflammable. It could ignite if it comes intocontact withhot engine component parts ortheexhaust system.
Make surethat no windshieldwasherconcentrate spills out nexttothefilleropening.
Removecap1bythetab.
Addwasherfluid.
Keepingthe air-water duct free
Keepthe area betweenthe hood andthewindshield free of deposits, e.g. ice, snowand leaves.
358Maintenance and care

Cleaning and care
Information onwashingthevehicle in a carwash
\nWARNINGRisk of accident duetoreduced braking effect afterwashingthevehicle
The braking effect isreduced afterwashingthevehicle.
Afterthevehicle has beenwashed,brake carefully while paying attentiontothe traffic conditions untilthe brakingeffect has been fullyrestored.
NOTEDamageduetounsuitable carwash
Before driving into a carwash makesurethatthe carwash is suitableforthevehicle dimensions.
Ensurethere is sufficient ground clear‐ance betweenthe underbody andtheguiderails ofthe carwash.
Ensurethatthe clearance width ofthecarwash, in particularthe width oftheguiderails, is sufficient.
Toavoid damageto yourvehicle when using acarwash, ensurethefollowing beforehand:
RActive Distance AssistDISTRONIC andtheHOLD function are deactivated.
Rthe 360° Camera ortherear view camera isswitched off.
Rthe side windowsand sliding sunroof arecompletelyclosed.
Rthe blowerfortheventilation/heating isswitched off.
Rthe windshield wiper switch is in positionZ.
Rin carwashes with a conveyor system: neu‐tral\\is engaged.
Rthe SmartKeyis at a minimum distance of10ft(3 m)awayfromthevehicle,otherwisethe trunk lid could open unintentionally.
Ifyouwould liketoleavethevehicle while itis beingwashed, make surethe SmartKeyis
located inthevehicle. The]gear isother‐wise automatically engaged.
If, afterthe carwash,youremovethewaxfromthe windshield and wiperrubbers,thiswill prevent smearing andreduce wipernoise.
Information on using a powerwasher
\nWARNINGRisk of accident when usinghigh-pressure cleaning equipment withround-spraynozzles
Thewater jet from around-spraynozzle (dirtgrinder) may cause damagetotires and sus‐pension componentsthat is not visible.
Components damaged inthisway mayfailunexpectedly.
Do not use high-pressurecleaningequipment withround-spraynozzlestocleanyourvehicle.
Damaged tires or suspension compo‐nents must bereplaced immediately.
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