engine MERCEDES-BENZ C-CLASS CABRIOLET 2021 Repair Manual

Ve
hicle identif ication plate(Canada only)
1 Maximum permissible gross vehicle weight
2 Maxim umpermissib lefront axle load
3 Maxim umpermissib lerear axle load
4 Paint code
5 VIN (vehicle identificat ion numb er)
The maxim umpermissib legross vehicle weight
is made upoftheve hicle weight ,all vehicle
occupants, thefuel andtheload. Themaximum
gr oss axle weight rating isthemaximum weight
th at can becar ried on one axle (front orrear
axle ). Do
notexc eed themaximum gross vehicle
we ight orthemaximum gross axle weight rating
fo rth efront orrear axle .
VIN belo wright- hand front seat 1
Imprint ed VIN (vehicle identification number )
2 Floor covering Ad
diti onalplat es 1
Engine numberstam ped intoth ecr ankc ase
2 Platewit hinf ormation aboutemissions test‐
ing, including confirm atio nof emis sions
guideli nesattheU. S. feder alleve las wellas
fo rCa lifor nia
3 VIN (vehicl eidentif icationnumber) asalab el
at thelowe redg eof thewindshield 388
Tech nica lda ta

#
Fire,ope nflames ,smo kingand creat ion
of spar ksmus tbe avo ided. #
Swit choffth eignition and,ifav ailable,
th est atio naryheat er,bef oreand while
re fuel ingtheve hicle. &
WARNIN GRisk ofinju ryfrom fuels
Fu els arepoisonous andhazar dous toyour
healt h. #
Donotsw allo wfuel orletit co me into
co ntact withsk in, eyes orclo thing. #
Donotinhale fuelvapor . #
Keep childr enaway from fuel. #
Keep door sand windo wsclos edduring
th ere fuel ingprocess.
If yo uor other people comeintocont actwith
fuel, obser vethefo llo wing: #
Imm ediat elyrinse fuelof fyo ur skin wit h
soap andwater. #
Iffuel comes intocont actwithyo ur
ey es, immediat elyrinse them thor‐ oughl
ywit hclean water.Seek medical
att entio nimm ediately . #
Ifyo usw allo wfuel, seek medicalatten‐
tio nimm ediat ely. Do notind uce vomit‐
ing. #
Cha ngeimmedi ately out ofclo thing that
has com eint ocon tact with fuel . Fle
xible -fuel vehicles canberefuel edwithth e
fo llo wing fueltypes:
R Unleaded premium grade gasoline
R E85 fuel
R Amixtur eof E85 fuelandunleade dpr emium
gr ade gasoline
Fle xible-fuel vehicles canbeidentif iedbythe
Et ha nol uptoE85 sticke ron theinside ofthe
fuel filler flap.
De pen dingon thecount ry,th efuels youcan use
in your vehicle maydif ferfr om theinf ormation in
th eOper ator's Manual. Thefuels that have been
appr oved foryo ur vehicle canbefound onthe
ins truct ion label ontheinside ofthefuel filler
fl ap. Fu
el No
teson fuel grades forve hicl eswith aga s‐
oline engine
Obser vetheno teson oper ating fluids
(/ page38 9).
* NO
TEDama gecau sed bythewr ong fuel Ev
en small amounts ofthewr ong fuelcould
re sult indamag eto thefuel system, the
engine andtheemission control system. #
Onlyre fuel withlow- sulfur gasoline.
This fuelmaycont ainupto10%ethanol by
vo lume. Your vehicle issuit able foruse with
E1 0fuel .
Ne verre fuel withone ofthefo llo wing fuels:
R Dies el
R Gasoline withmor eth an 10%ethanol by
vo lume, e.g.E15, E8 5,E100
R Gasoline withmor eth an 3% methano lby
vo lume, e.g.M15,M30 ,M85 ,M1 00
R Gasoline withadditiv escon tainin gme tal 390
Tech nica lda ta

If
yo uha ve acc iden tally re fuel edwithth e
wr ong fuel: #
donotswit chtheignition on. #
Consult aqu alif ied spec ialistwo rkshop. If
th eav ailable fuelisno tsuf ficie ntly low in sul‐
fur ,th is can produce unpleasant odors.
Onl yre fuel withfuel that has atleas tth eoct ane
number specifiedintheinf ormation labelinthe
fuel filler flap (/ page14 1).
If yo uwa ntmaxim umengine output:onl y
re fuel withunle adedpr emiu mgrade gasoline
wit han oct ane number ofat leas t91 AKI/
95 RON.
As ate mp orar ymeasur e,ifth ere comme nded
fue lis no tav ailable, youma yalso refuel with
unle adedre gular gasoline withat leas t87 AKI/
91 RON.Thisma yre duce engineoutput and
incr ease fuelconsum ption.
Ne verre fuel using gasoline withan eve nlowe r
RO N. *
NO
TEPrema turewe arthro ugh unleaded
re gular gasoline Un
leade dre gular gasoline cancause the
engine towe armor equ ickl yand impair lon‐
ge vity and perform anc e.
If unle aded premium grade gasoline is
una vailable andyouha ve torefuel using
unle adedre gular gasoline: #
Onlyfill th efuel tank tohalf fullwith
unleaded regular gasoline andrefill as
soon aspossible withunleaded pre‐
mium grade gasoline. #
Donotdr ive at themaximum design
speed. #
Avoid sudden accelerationengine
speeds over3000 rpm. Fu
rther information onfuel isavailable atthefo l‐
lo wing locations:
R ataga sst atio n
R ataqu alif ied spec ialistwo rkshop
R onthehtt ps:/ /www .mbusa.c om(USAonl y) No
teson add itivesingasoline
Obser vetheno teson oper ating fluids
(/ page38 9).
* NO
TEDama gefrom use ofunsu itabl e
add itives Ev
en smal lamou ntsofthewr ong additiv e
ma ylead tomalfu nctions occurring. #
Only addcle ani ng additiv es recomme n‐
ded byMer cedes-Ben zto thefuel. Mer
cedes- Benzrecomme ndsthat youuse
br and -name fuels withaddit ives.
In som eco unt ries, thefuel available mayno t
ha ve suf ficie ntadditiv es. Residue could buildup
in thefuel injec tionsystem asare sult. Inthis
case, incon sult ation withan aut hor ized
Mer cedes -Benz Cent er,mix thefuel withth e
cle ani ng additiv ere comme ndedbyMer cedes-
Benz .Obser vetheno tesand mixing ratio sind i‐
cat edon theta nk . Te
ch nica lda ta 39
1

Ta
nk cont entand reser vefuel
Capacity Model
Total cap acity
Al lmo dels 17.4 gal(66. 0liter s) Model
ofwhic hre ser ve
fuel
All model s1 .8gal(7 .0 liter s) Engine
oil No
teson engine oil
Obser vetheno teson oper ating fluids
(/ page38 9). *
NO
TEEngi nedama gecau sed byan
inc orrect oil filt er ,inc orrect oil oraddi‐
tiv es #
Donotus eengi neoilsor oil filt er sot her
th an those whic hmee tth especif ica‐
tion sneces saryfo rth epr escr ibed
ser vice interva ls. #
Donotalt er theengine oiloroil filt er in
or der toachie velong erchang eint erva ls
th an presc ribed. #
Donotuse additiv es. #
Have theengine oilchang edafte rth e
pr escr ibed interva ls. Mer
cedes -Benz recomme ndsthat youha ve the
oil chang ecar ried out ataqu alif ied spec ialist
wo rkshop.
Quality andcapacity ofengine oil
MB-F reigabe orMB- Appr oval Gasol
ineeng inesE ngineoilspecif ica‐
tions
All models 229.51,229 .52,
229 .61
229 .71* *
Re comme ndedforlo we stpossible fuelcon‐
sum ption (lowe stSA Evis cos ityclassineach
case ;obs erve possible restrictions ofthe
appr ovedSA Evis cos ityclasse s).
To achie vethelowe stpossible fuelconsum ption,
it is recomme ndedtouse theengine oilspecif i‐
cation smar kedin theta ble forth elowe stSA E
viscosi tyclass .Po ssible restrictions ofthe
appr ovedSA Evis cos ityclasse smu stbe
obser ved.
The follo wing values referto an oilchang e,
inc ludin gth eoil filt er . 392
Tech nica lda ta

Re
plac eme ntamoun t Mode
lR eplacement
am ount
C 300 7.0 US qt(6.6 liter s)
C 300 4MATIC 6.3USqt(6.0 liter s) No
teson brak efluid Obser
vetheno teson oper ating fluids
(/ page38 9). &
WARNIN GRisk ofan acci dent dueto
va por pockets form ing inthebr ak esy s‐
te m
The brak efluid constantly absor bsmoi stur e
fr om theair .This lowe rstheboiling pointof
th ebr ak efluid. Ifth eboiling pointistoolow,
va por pockets ma yfo rm inthebr ak esy stem
when thebr ak es areapplied hard.
This causes thebr aking effect to be
im pair ed. #
Have thebr ak efluid rene we dat the
specif iedinterva ls. Ha
ve thebr ak efluid regular lyreplaced ata
qu alif ied spec ialistwo rkshop.
Onl yuse abr ak efluid appr ovedby Mer cedes-
Benz accor dingtoMB-F reigabe orMB- Appr oval
33 1.0. Co
olan t No
teson coolant
Obser vetheno teson oper ating fluids
(/ page38 9). &
WARNIN G‑Ri sk offire and injuryfrom
ant ifreez e
If ant ifreez ecom esintocon tact with hot
com ponent partsintheengine compart‐
ment ,it ma yignit e. #
Allo wtheengine tocool down before
ad ding anti freeze . #
Makesur eth at no ant ifreez espills out
ne xt to thefiller open ing. #
Thor oughl yclean offan yant ifreeze
fr om com pone ntpar tsbef orest ar tin g
th eve hicle. *
NO
TEDama gecau sed byinc orrect cool ‐
ant #
Onlyus ecool antthat has been pre‐
mix edwithth ere qu ired ant ifreeze pro‐
te ction.
Inf ormati ononcool antisavailable atthefo l‐
lo wing locations:
R IntheMer cedes- BenzSpecif ication sfo r
Oper ating Fluids 310.1
- Athttps: //bevo.mer cedes-b enz.com
- IntheMer cedes- BenzBeVoapp
R Ataqu alif ied spec ialistwo rkshop *
NO
TEOverhea ting athigh outsid ete m‐
per atur es If
an inapp ropr iat ecoolant isused, the
engine cooling system isno tsuf ficie ntlypr o‐ Te
ch nica lda ta 393

te
cted agains tov erheating andcorrosion at
high outside temp eratur es. #
Alw aysuse coolant approvedby
Mer cedes-Ben z. #
Obser vetheins truction sin the
Mer cedes-Ben zSpecif ications forOper‐
ating Fluids310.1. Ha
ve thecoolant regular lyreplaced ataqu alif ied
spec ialistwo rkshop.
Pr opor tionofantifr eezeconcen trat ein the
engine cooling system:
R Aminimum of50% (antifr eezeprotect ion
do wn toappr oximat ely-3 5°F (-37°C))
R Amaxim umof55% (antifreeze protect ion
do wn to-49°F (-45°C))
Co olant capacity Mode
lC apacity
All mode ls 9.5USqt(9.0 liter s) No
teson windshield washer fluid Obser
vetheno teson oper ating fluids
(/ page38 9). &
WARNIN G‑Ri sk offire and injuryfrom
wind shieldwa sher concen trat e
Wi ndsh ield wa sher concen trat eis highly
fl ammab le.Itcoul dign ite if it com esinto
con tact with hotengine component partsor
th eex haus tsy stem. #
Mak esur eth at no wind shieldwa sher
concen trat espills outnext to thefiller
open ing. *
NO
TEDama getotheex terior lighting
due touns uitable windshieldwa sher fluid Uns
uitable windshieldwa sher fluid maydam‐
ag eth eplas ticsur face oftheex terior light‐
ing. #
Onlyuse windshield washer fluid whic h
is also suitable foruse onplastic sur fa‐
ces, e.g.MBSumm erFitor MB Winter‐
Fit. *
NO
TEBlocked spr aynozzl escau sed by
mixing windshieldwa sher fluids #
Donotmix MBSum merFitand MBWin‐
te rFit withot her windshield washer flu‐
ids. Do
notuse distilled orde- ionizedwa ter.Ot her‐
wise, thefill le ve lsen sor maybe trigg ered erro ‐
neou sly.
Re comme ndedwindsh ield wa sher fluid:
R Abo vefreezing point:e.g. MBSummerFi t
R Belo wfreezing point:e.g. MBWinterFi t
Fo rth ecor rect mixi ngratio ,re ferto theinf orma‐
tion ontheantif reeze container .
Mix washer fluid withwind shieldwa sher fluid all
ye ar round . Re
frig er ant No
teson refrig er ant
Obser vetheno teson oper ating fluids
(/ page38 9). 39
4
Tech nica lda ta

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
Á Key NotDetected (red dis‐
pla ymessag e) *T
heSmar tKey canno tbe detected and mayno long erbe intheve hicle.
The Smar tKey isno long erintheve hicle andyouswit choffth eengine:
R Youcan nolongerst ar tth eengine.
R Youcan notcen trally lockth eve hicle. #
Ensur eth at theSmar tKey isin theve hicle.
If th eSmar tKey detection functi onhasa mal functi ondueto ast ro ng radio signal source: #
Stop theve hicle immediat elyinaccor dance withth etraf fic condi tions. #
PlacetheSmar tKey inthemar kedspace forst ar tin gth eengine withth eSmar tKey (/ pag e12 6).
Á Don't ForgetYour Key *A
warning tone also sou nds. Thismes sage reminds youto take your Sm artK ey wit hyo uwhen youlea vetheve hicle.
Place theKey inthe
Marked SpaceSeeOpera-
tor's Manual *S
mar tKey detection ismal functi oning. #
Chang eth elocation oftheSmar tKey intheve hicle. #
Place theSmar tKey inthemar kedspace forst ar tin gth eengine withth eSmar tKey (/ pag e12 6). Dis
play messa gesand warning/ indic ator lam ps 403

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
0059 Open/Close Convertible
Top Completely *T
hesof tto pis no tloc ked. Ifyo udr ive at spee dsgrea terth an 37 mph(60 km/h), youcan notopen orclo sethesof t
to p. #
Donotdr ive at speeds great erthan 37 mph(6 0km/h). #
Fully open orclos eth esof tto p.
0059 12 VBatt erySee Opera-
tor' sManual *T
heon-boar delectr icalsystem voltag eis toolow. #
Startth eengine.
0058
Trunk PartitionOpen *T
hetrunk partition isopen. #
Close thetrunk partition. Displa
ymessag esand warning/ indic ator lam ps 405

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
0084 *T
hetrunk lidisopen. &
DANG ER Risk ofexhaus tga spoisoning
Combus tionengines emitpoisonous exhaus tga ses suchas carbon monoxide.Exhaus tga ses can enterthe
ve hicle interior ifth etrunk lidisopen when theengine isrunning ,esp ecially ifth eve hicle isin mo tion. #
Alw aysswitc hof fth eengine beforeopening thetrunk lid. #
Neverdr ive wit hth etrunk lidopen. #
Close thetrunk lid.
006F
Rear LeftBack restNot
Latc hed (exa mp le) *T
heseat backres tof thecor responding seatisno teng aged. #
Foldtheseat backres tbac kuntil iteng ages.
006F Fron tLeft Seat Backrest
Not Lock ed(exa mp le) *T
heseat backres tof thecor responding front seat isno teng aged. #
Foldtheseat backres tbac kuntil iteng ages. Displa
ymessag esand warning/ indic ator lam ps 41
1

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
00B2 Check Washer Fluid *T
hewasher fluid leve lin thewa sher fluid reser voirhas dropped belowtheminimum. #
Addwa sher fluid (/ page32 2). Engine
Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
To switch engine off,press
and hold Start/S topbut-
ton foratleast 3secs. or
press 3times. *Y
ouhave pressed thest ar t/ stop butt onwhile theve hicle isin mo tion. #
Information aboutswitchingoffth eengine whiledriving (/page12 5).
00BD
Che ckCoo lant Level See
Opera tor'sManu al *T
hecoolant leve lis toolow.
* NO
TEEngi nedama gedue toinsuf ficie ntcool ant #
Avoid long journeys wit hins ufficie ntcool ant. #
Addcoolant (/page322 ). #
Have theengine cooling system checkedat aqu alif ied spec ialistwo rkshop. 41
2
Display messa gesand warning/ indic ator lam ps