2019 MERCEDES-BENZ S CLASS engine

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:
,Service.ASSYST 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 252).
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 395).
Engine compartment
Active hood (pedestrian protection)
Operation ofthe active hood (pedestrian pro‐tection)In certain accident situations,therisk of injurytopedestrians can bereducedbythe actuationofthe active hood. Therear area ofthe hood israisedbyapproximately 80 mm.
Forthe drivetotheworkshop,resetthe trig‐gered active hoodyourself. Afterthe active hoodhas been triggered, pedestrian protection maybe limited.
Aqualified specialistworkshop mustre-instatethe full functionality ofthe active hood.
The active hood is notavailable in all countries.
Resettingthe active hood
&WARNINGRisk 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.
#Withyour handflat, push down active hood1inthe area aroundthe hinges on bothsides (arrows).The hood must engage in position.
#Ifthe active hood can beraised slightly attherear inthe area ofthe hinges,repeatthestep until it engages correctly.
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Opening/closingthe hood
&WARNINGRisk 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.
&WARNINGRisk 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.
&WARNINGDanger 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.
&WARNINGRisk 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.
#Nevertouchthe danger zone surround‐ing moving component parts, e.g.therotation area ofthefan.
#Removejewelry andwatches.
#Keep items of clothing and hairawayfrom moving parts.
&WARNINGRisk 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.
&WARNINGRisk 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.
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#Allowthe enginetocool down and onlytouch component parts described inthefollowing.
&WARNINGRisk 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.
Plug-inhybrid:observethe notes inthe Supple‐ment. Otherwise,you mayfailtorecognize dan‐gers.
#Toopen:pull lever1toreleasethe hood.#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.
398Maintenance and care

Engine oil
Checkingthe engine oil level usingthe oildipstick
&WARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain component parts inthe engine com‐partment can beveryhot, e.g.the engine,the cooler and parts oftheexhaust system.
#Letthe engine cool down and onlytouchthe component parts describedasfollows.
Plug-inhybrid:observethe notes inthe Supple‐ment. Otherwise,you mayfailtorecognize dan‐gers.
Requirements:RThe engine must havean oil dipstick.If not,the engine oil level can bechecked only withthe on-board computer (→page 399).
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, and pull it out again afterapproximatelythree seconds.ROil level is correct: oil level is between2and3.
ROil leveltoo low: oil level is at3orbelow.
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, havetheexcessengine oilremoved as soon as possible at aqualified specialistworkshop.
Checkingthe engine oil level with an on-board computer
Requirements: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.
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RParkthevehicle on a level surface.
RLeavethe enginerunning at idle speed.
On-board computer:
,Service.Engine Oil Level
You will see one ofthefollowing messages inthe multifunction display:
#Measuring Engine Oil Level...: measurementofthe oil level is notyet possible.Repeattherequest after a maximum of 30 minutes' driv‐ing.
#Engine Oil Level OKandthe bar displayforindicatingthe oil level inthe multifunctiondisplay is green and is between "min" and"max":the oil level is correct.
#Engine Oil Level Add 1.0 landthe bar displayfor indicatingthe oil level inthe multifunctiondisplay is orange and is below "min": add1.1 US qt (1 liter) of engine oil.
#Reduce Engine Oil Levelandthe bar displayfor indicatingthe oil level inthe multifunctiondisplay is orange and is above"max": drain
offtheexcess engine oil. Consult aqualifiedspecialistworkshop.
#For Engine Oil Level Switch Ignition On:switch onthe ignitiontocheckthe engine oillevel.
#Engine Oil Level System Inoperative: sensordefective or not inserted. Consult aqualifiedspecialistworkshop.
#Engine Oil Level System Currently Unavail.:closethe hood.
Adding engine oil
&WARNINGRisk 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.
&WARNINGRisk 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.
400Maintenance and care

#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 399).
Checking coolant level
&WARNINGRisk 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.
&WARNINGRisk 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.
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#Parkthevehicle on a level surface.
#Checkthe coolanttemperature display intheinstrument cluster.The coolanttemperature must be below158 °F (70 °C).
#If necessary,removethe cover.
#Slowly turn cap1counter-clockwisetorelieve overpressure.
#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:(→page472)
Addingwasherfluidtothe windshieldwasher system
&WARNINGRisk of burns from hot com‐ponent parts inthe engine compartment
Certain component parts inthe engine com‐partment can beveryhot, e.g.the engine,the cooler and parts oftheexhaust system.
#Letthe engine cool down and onlytouchthe component parts describedasfollows.
&WARNINGDanger 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.
&WARNING‑ 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.
402Maintenance and care