engine MERCEDES-BENZ C-CLASS CABRIOLET 2021 Workshop Manual

All
vehicl es
+ ENVIR
ONMENT ALNOTEEnvironme ntal
da ma gecau sed byimproper disposal of
batt eries Bat
teries con tain polluta nts. Itis
illeg alto dispose ofthem withth ehousehold
ru bbish. #
Dispose
ofbatt eries inan
en vironmen tally re sponsible manner.
Ta ke disc hargedbatt eries toaqu alif ied
spec ialistwo rkshop ortoacol lection
poin tfo rused batteries. If
yo uha ve todiscon nectth e12 Vbatt ery, con‐
ta ct aqu alif ied spec ialistwo rkshop.
Com plywit hsaf etyno tesand take protect ive
measur eswhen handling batteries. Risk
ofexplosion. Fir
e,open flames andsmokingar e
pr ohibi tedwhen handling thebatt ery.
Av oid creating sparks. Ele
ctroly teor batt eryacid iscor ro‐
siv e.Avoid cont actwithth eskin ,eye s
or clo thing. Wearsuit able protect ive
clo thing, inpar ticular glove s,an
apr onand afa ce mas k.Immedia tely
ri nse electr olyteor acid splashes off
wit hclean water.Con sult adoc torif
necessar y. We
arsaf etygl asses . Ke
ep childr enaway. Obser
vethis Opera tor's Manua l.
Obser vethefo llo wing ifyo udo notint endto use
th eve hicle overan extende dpe riod oftime:
R Activatest andb ymode .
R Alternat ivel y: con nectth ebatt eryto abat ‐
te ry charge rapp rove dby Mer cedes-Ben zor
consult aqu alif ied spec ialistwo rkshop to
discon nectth ebatt ery. No
teson star ting assistance andchargin g
th e12 Vbatt ery Ve
hicl eswith alithium-ion battery
When chargin gth ebatt eryand during star tin g
assis tance, alwa ys use thejum p-start connec‐
tion pointintheengine compartmen t. 34
2
Brea kdo wnassista nce

*
NO
TEDama getothebatt eryfrom over‐
vo ltag e When
chargin gusin gabat tery charge rwit h‐
out amaximu mchargin gvo ltag e, thebatt ery
or theon- boar delectr onics maybe damag ed. #
Onlyuse batterych arge rs wit hamax i‐
mum chargin gvo ltag eof 14.8 V. All
other vehicl es
When chargin gth ebatt eryand during star tin g
assis tance, alwa ys use thejum p-start connec‐
tion pointintheengine compartmen t.
* NO
TEDama getothebatt eryfrom over‐
vo ltag e When
chargin gusin gabat tery charge rwit h‐
out amaximu mchargin gvo ltag e, thebatt ery
or theon- boar delectr onics maybe damag ed. #
Onlyuse batterych arge rs wit hamax i‐
mum chargin gvo ltag eof 14.8 V. &
WARNIN GRisk ofexplosion from hydro‐
ge nga signiting
Ther eis adang erofhydrog en gasigniting
when chargin gth ebatt eryif th er eis ashor t
cir cuit orspar ksstar tto form . #
Mak esur eth at thepositiv ete rm inal of
th econ nect edbatt erydoes notcome
int ocon tact with vehicle parts. #
Neverpla ceme talobje ctsor tools ona
batt ery. #
The descr ibedorder ofthebatt ery
clam psmus tbe obser vedwhen con‐
nec tingand discon nectingth ebatt ery. #
When giving star tin gassis tance, alwa ys
mak esur eth at youon lyconnect bat‐
te ry term inals withident icalpolar ity. #
Dur ing star tin gassis tance, youmus t
obse rveth edescr ibedorder forcon‐
necting anddisconnecting thejum per
cable. #
Donotcon nect ordiscon nectthebat‐
te ry cla mp swhile theengine isrunning . &
WARNIN GRisk ofexplosion during
ch argin gpr oce ssand star tin gassis tance
Dur ing thech argin gpr oce ssand star tin g
assis tance, thebatt eryma yre lease anexplo‐
siv ega smixtur e. #
Avoid fire ,open flames ,cr eat ing spar ks
and smoking. #
Mak esur eth er eis suf ficie ntventil a‐
tio n. #
Donotle an ove ra batt ery. &
WARNIN GRisk ofexplosion from afro‐
zen battery
A disc hargedbatt eryma yfreeze attemp era‐
tur es slightl yabo veorbelo wfreezing point.
Dur ing star tin gassis tance orbatter ych arg‐
ing ,bat tery gascan bereleased. #
Alw aysallo wabatt eryto thaw before
ch argin git or per form ing star tin gassis ‐
ta nce. Br
ea kdo wnassist anc e34
3

If
th eindicat or/warning lampsintheins trument
clus terdo notlig ht up atlow temp eratur es,itis
ve ry likelyth at thedisc hargedbatt eryhas fro‐
zen .In this case youma yne ither jump-start the
ve hicle norcharge thebatt ery.
The service life of abatt eryth at has been
th awe dma ybe dramaticall yshor tened .The
st ar tin gch aract eristic sma ybe impair ed,espe ‐
ciall yat low temp eratur es.
It is recomme ndedthat youha ve ath aw ed bat‐
te ry checkedat aqu alif ied spec ialistwo rkshop.
All vehicl es
* NO
TEDama gecau sed bynum erou sor
ex tende datt em ptsto star tth eengine Nu
me rous orextende datt em ptsto star tth e
engine maydamag eth ecat alytic converter
due tonon-co mbusted fuel. #
Avoid numer ousand extende datt em pts
to star tth eengine. Obser
vethefo llo wing pointsdur ing star tin g
assis tance and when chargin gth ebatt ery:
R Onlyuse undamag edjum per cables/c harg‐
ing cables withasuf ficie ntcross -secti onand
insu late dte rm inal clam ps.
R Non-insulat edpar tsof thete rm inal clam ps
mus tno tcom eint ocon tactwi th other metal
par tswhile thejum per cable/c harging cable
is con nect edtothebatt ery/jum p-start con‐
nectio npoi nt.
R The jumper cable/c harging cable mustno t
com eint ocon tactwi th anypar tswhic hma y
mo vewhen theengine isrunning .
R Alw aysmak esur eth at nei ther youno rth e
batt eryis elect rostatic allych arge d.
R Keep away from fire and open flames .
R Donotlean overth ebatt ery.
Obser vetheadditional follo wing pointswhen
ch argin gth ebatt ery:
R Onlyuse batterych arge rs tested and
appr oved forMer cedes-Benz.
R Read thebatt erych arge r's oper ating instruc‐
tions beforech argin gth ebatt ery. Obser
vetheadditional follo wing pointsdur ing
st ar tin gassis tance:
R Startin gassis tance mayonly beprov ided
using vehicles, batteries orother jumpstar t
de vic es wit hano min alvoltag eof 12 V.
R The vehicles mustno tto uc h.
R Vehicl eswith aga soline engine: Jump
st ar tth eve hicle onlywhen theengine and
ex haus tsy stem arecold. St
arting assistance andchargin gth e12 V
batt ery Pr
epar ingstar ting assistance /char ging #
Secur eth eve hicle byappl ying theelectr ic
par king brak e. #
Automatic trans mis sion :Shi ftthetra ns‐
mission toposition 005D. #
Manu altransm ission: Shiftth etra nsmis‐
sion toneu tral . #
Swi tchof fth eignition andallelectr icalcon‐
sumer s. #
Open thehood. 34
4
Brea kdo wnassista nce

#
Foldcover1 upinthedir ect ion ofthe
ar row . #
Slide cover2 ofposi tiveclam p3 onthe
jum p-starting con nection point inthedir ec‐
tion ofthear row .
St arting assistance #
Connect positivecont act3onyour vehicle
to thepositiv ete rm inal ofthedonor battery
using thejum per cable. Alwaysbegin with
positiv eclam p3 onyour ow nve hicle firs t. #
Startth eengine ofthedonor vehicle andrun
it at idling speed. #
Conn ecttheneg ativete rm inal ofthedonor
batt eryto grou nd point 4 ofyour vehicle
using thejum per cable. Beginwithth edonor
batt eryfirs t. #
Startth eengine ofyour ow nve hicle. #
Letth eengines runfo rse veralmin utes. #
Beforedisco nnect ing thejum per cables,
switc hon anelectr icalconsumer inyour ow n
ve hicle, e.g.there ar wind owheat eror the
light ing.
When thest ar tin gassis tance proce dure iscom ‐
ple te: #
First,re mo vethejum per cables from ground
point 4and theneg ativete rm inal ofthe
donor battery, then from positiv econ tact 3
and thepositiv ete rm inal ofthedonor bat‐
te ry.Begi nea ch tim ewi th thecon tacts on
yo ur ow nve hicle firs t. #
Afterre mo ving thejum per cables, close
co ver2 ofposi tivecont act3. #
Closecover1. Br
eakdo wnassi stanc e34
5

4MA
TICvehicl es/vehicl eswith automatic
tr ansmiss ion #
Mak esur eth at thefront and rear axle scom e
to rest on thesame transpor tatio nve hicle.
* NO
TEDama getothedr ivet ra in due to
inc orrect pos itioning #
Donotpos ition theve hicle abovethe
connecti onpointofthetranspor tve hi‐
cle. To
wing eyesto rage location The
towing eyeis locat edinthestor ag espace
under thetrunk floor . Ins
talling theto wing eye #
Press themar kon cover1 inwa rdsand
re mo ve. #
Screw intheto wing eyecloc kwiseasfaras it
wil lgo and tight en. #
Mak esur eth at cover1 eng ages inthe
bum perwhen youre mo vetheto wing eye.
* NO
TEDama getotheve hicle dueto
inc orrect useof theto wing eye When
ato wing eyeis used toreco vera ve hi‐
cle, theve hicle maybe damag edinthepr oc‐
ess. #
Onlyuse theto wing eyeto tow aw ay or
to w star tth eve hicle. To
w star ting theve hicl e(eme rgency engine
st ar t) Ve
hicl eswith automatic transmiss ion
* NO
TEDama getotheaut omatic trans‐
mission duetotow star tin g The
automat ictransm issionma ybe damag ed
in thepr ocess oftow star tin gve hicles with
aut omatic transmission. 350
Breakdo wnassis tance

#
Vehicles withaut omatic transmission
mus tno tbe tow star ted. #
Vehicles withaut omatic transmission must
no tbe tow- star ted. Electr
icalfuses No
teson electr icalfuses &
WARNIN GRisk ofacci dent andinjury
due tooverloaded lines
If yo uman ipulat eor bridg eafa ulty fuse orif
yo ure place itwit hafuse withahigher
am per age, theelectr icline could beove rloa‐
ded.
This could result inafire . #
Alw aysre place faulty fuseswit hspec i‐
fi ed newfuses containin gth ecor rect
am per age. *
NO
TEDama gedue toinc orrect fus es Electr
icalcom pone ntsorsystems maybe
damag edbyinc orrect fus es, ortheir func ‐
tion ality maybe signif icantlyim pair ed. #
Onlyuse fuses that have been approved
by Mer cedes-Ben zand whic hha ve the
cor rect fus era ting . Blo
wn fuse smu stbe replaced withfuses ofthe
same rating ,wh ich yo ucan recogni zeby the
colo rand thelabeling. Thefuse rating sand fur‐
th er information tobe obser vedcan befound in
th efuse assignmen tdiagr am.
Fu se assignment diagram: onthefuse boxin
th etrunk (/page353).
* NO
TEDama geormalfunct ionscaused
by mois ture Mois
turema ycause damagetotheelectr ical
sy stem orcause itto malfu nction. #
When thefuse boxis open, makesur e
th at no mois turecan enterthefuse
bo x. #
When closing thefuse box,mak esur e
th at theseal ofthelid isposition edcor‐
re ctly onthefuse box. If
th ene wlyinser tedfuse alsoblows,ha ve the
cau setrace dand rectif ied at aqu alif ied spec ial‐
is two rkshop.
Ensur eth efo llo wing beforere placing afuse:
R The vehicle issecur edagains tro lling away.
R Allelectr icalconsu mersar esw itched off.
R The igniti onissw itched off.
The electr icalfu ses arelocat ed invarious fuse
bo xes:
R Fuse boxin theengine compartmen ton the
dr iver's side (/page352)
R Fuse boxon thedr iver's side ofthecoc kpit
(/ page353)
R Fuse boxin thefront passeng erfoot we ll
(/ page353) Br
eakdo wnassis tance 35
1

R
Fuse boxin thetrunk ontheright- hand side
of theve hicle, when viewe din thedir ect ion
of tra vel(/ page353) Opening
andclosing thefus ebo xin the
engine compartmen t Re
quirement s:
R Adr yclo thand asc rewdr iver areav ailable.
Obse rveth eno teson electr icalfuses
(/ page35 1).
Opening &
WARNIN GRisk ofinju ryfrom using the
winds hieldwiper swhile theengine hood
is open
When theengine hoodisopen andthewind‐
shield wipersar ese tin mo tion ,yo ucan be
trapped bythewiper linkage. #
Alw aysswitc hof fth ewindshield wipers
and ignition beforeopening theengine
hood. #
Turn retainin gclip 2oncover1 aqu arter-
tur ncou nter-clo ckwise. #
Foldcover1 upinthedir ect ion ofthe
ar row . #
Remo veanyex istin gmois turefrom thefuse
bo xusing adr yclo th. #
Loosen screws3 and remo vefuse boxlid
4 upw ards.
Clo sing #
Che ckwhe ther theseal isposition edcor‐
re ctly inlid 4. 352
Brea kdo wnassista nce

%
Dep endingontheve hicle equipment, the
to ol bag maybe locat edatother positions in
th etrunk . The
tool bag cont ains:
R Jack
R Gloves
R Lugwr enc h
R Alignmen tbolt
R Folding choc k
R Ratche tfo rjac k Pr
epar ingtheve hicl efo ra wh eelch ang e Re
quirement s:
R The requ ired tire-c hang eto ol kit isavailable.
If yo ur vehicle isno teq uipped withth etir e-
ch ang eto ol kit, consult aqu alif ied spec ialist
wo rkshop tofind outab ou tsu itab letools.
R The vehicle isno ton aslope.
R The vehicle ison solid, non-slipper yand leve l
gr ou nd . #
Apply theelectr icpar king brak emanually . #
Movethefront wheels tothest ra ight -ahead
posit ion. #
Vehicl eswith automatic transmiss ion:
Shif tint oposi tion 005D. #
Vehicl eswith leve lcontr olsystem: Setth e
nor malve hicle leve l(/ page18 3). #
Swi tchof fth eengine. #
Mak esur eth at theengine cannotbe star ted. #
Place choc ks orother suitable items under
th efront and rear ofthewheel that isdiago‐
nall yoppos ite th ewheel youwish tochang e. #
Ifnec essar y,remo vethewheel trim/hub
caps (/page37 8). #
Raise theve hicle (/page37 9). Re
mo ving and inst alli ng thewheel trim/h ub
cap s Re
quirement s:
R The vehicle isprepar edfora whee lch ang e
(/ page37 8).
Pl as tic hub cap #
Toremo ve:tur nth ecent ercoverof thehub
cap count er-cloc kwise andremo vethehub
cap. #
Toins tall: makesur eth at thecent ercover
of thehub capistur ned count er-cloc kwise. #
Position thehub capand turnth ecent er
co vercloc kwise untilthehub capengages
ph ysicall yand audibly . 37
8
Wheels andtires

Alum
inum hubcap #
Toremo ve:po sitio nsoc ket2 from thetir e-
ch ang eto ol kit onhub cap1. #
Position wheel wrenc h3 onsoc ket2. #
Usingwheelwr enc h3, turnhu bcap 1
cou nter-clo ckwise andremo veit. #
Toins tall: follo wtheins truction sabo vein
re ve rseor der .
% Specif iedtight ening torq ue: 18lb-f t
(25 Nm). Ra
ising theve hicl ewhe nch angi ngawhe el Re
quirement s:
R Ther ear eno per sons intheve hicle.
R The vehicle hasbeen prepar edfora whee l
ch ang e(/ page37 8).
R The wheeltrims and hub caps have been
re mo ved(/ page37 8).
Im por tant noteson using thejac k:
R Use onlya ve hicle-specif icjac kth at has
been approvedby Mer cedes-Ben zto raise
th eve hicle.
R The jackis onl ydesigned forra ising and
holdin gth eve hicle fora shor ttime whilea
whee lis being chang edand notfo rmaint e‐
nance workund ertheve hicle.
R The jackmus tbe placed onafirm ,fl at and
no n-slip surface. Ifneces sary,use alar ge,
fl at, load- bearing,no n-slip unde rlay .
R The foot ofthejac kmus tbe position edverti‐
call yunder thejac ksuppor tpoint . Ru
les ofcon duct when theve hicle israised:
R Neverpla ceyour han dsorfeet und erthe
ve hicle.
R Neverlie under theve hicle.
R Donotst ar tth eengine anddonotre lease
th eelectr icpar king brak e.
R Donotopen orclose anydoor sor thetrunk
lid. Wheels
andtires 37
9

R
2G/3G /4G Ra
dio ope ratin gper mits forve hicl eco mp o‐
nent s
Manuf acturer informat ionabout wireless vehicle
com ponent scan befound usingth eke yphrase
"R adio operating per mits"intheDigit alOper a‐
to r's Manua lin theve hicle, ontheInt erne tand
in theapp. Ve
hicl eiden tificati onplat e,VIN and engine
number overview
Ve hicl eiden tificati onplat e Ve
hicle identif ication plate(US Aonl y)
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) Te
ch nica lda ta 38
7