engine MERCEDES-BENZ C-CLASS CABRIOLET 2020 Workshop Manual

Chec
kingcoolant leve l &
WARNIN GRisk ofburnsfrom hotcom‐
ponent partsintheengine compartmen t
Cer tain com pone ntsin theengine compart‐
ment canbevery hot,e.g. theengine, the
ra diat orand partsof theex haus tsy stem. #
Allo wtheengine tocool down and only
to uc hco mp onent partsdescr ibedin
th efo llo wing. &
WARNIN GDang erofburnswhen open‐
ing thehood
If yo uopen thehood when theengine has
ove rheat edordur ing afire intheengine
com partmen t,yo uco uld come intoco ntact
wit hho tga ses orother escaping operating
fl uids. #
Beforeopen ingthehood, allowthe
engine tocool down. #
Intheeve ntofafire intheengine com‐
par tmen t,ke ep thehood closed and
call thefire ser vice. &
WARNIN GRisk ofscal ding from hot
cool ant
The enginecool ingsystem ispressur ized,
par ticular lywhen theengine iswa rm.If yo u
open thecap, youco uld bescalded byhot
coolant spraying out. #
Letth eengine cooldown beforeopen‐
ing thecap. #
When opening thecap, wearprotect ive
gl ove sand safetygl asses . #
Open thecap slowlyto release pres‐
sur e. #
Park theve hicle onaleve lsur face. #
Checkth ecoolant temp eratur edispla yin the
ins trumen tclus ter.
The coolant temp eratur emus tbe inthebo t‐
to m quarterof thete mp eratur edispla y. #
Slowly turncap 1cou nter-clo ckwise to
re lie ve ove rpressur e. Maint
enance andcare353

#
Con tinue turnin gcap 1count er-cloc kwis e
and remo veit.
The coolan tle ve lis cor rect inthefo llo wing
cases :
R ifth eengine iscold, uptomar kerbar 2
R ifth eengine iswa rm,up to0.6 in(1.5 cm)
ove rmar kerbar 2 #
Ifnecessar y,add coolant that has been
appr ovedfo rMer cedes-Benz.
R Further information oncoolant
(/ page428). Ad
ding washer fluid tothewindsh ield
wa sher system &
WARNIN GRisk ofburnsfrom hotcom‐
ponent partsintheengine compartmen t
Cer tain com pone ntsin theengine compart‐
ment canbevery hot,e.g. theengine, the
ra diat orand partsof theex haus tsy stem. #
Allo wtheengine tocool down and only
to uc hco mp onent partsdescr ibedin
th efo llo wing. &
WARNIN GDang erofburnswhen open‐
ing thehood
If yo uopen thehood when theengine has
ove rheat edordur ing afire intheengine
com partmen t,yo uco uld come intoco ntact
wit hho tga ses orother escaping operating
fl uids. #
Beforeopen ingthehood, allowthe
engine tocool down. #
Intheeve ntofafire intheengine com‐
par tmen t,ke ep thehood closed and
call thefire ser vice. &
WARNIN G‑Ri sk offire and injuryfrom
wind shieldwa sher concen trat e
Wi ndsh ield wa sher concen trat eis highl y
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. #
Remo vecap 1bytheta b. #
Addwa sher fluid. 35
4
Main tenance andcare

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 andoncharg‐
ing the12 Vbatt ery Ve
hicl eswith alithium-ion battery
When chargin gth ebatt eryand during star tin g
assis tance, alwa ys use thejum p-startconne c‐
tio npo int intheengine compartmen t. *
NO
TEDama ging thebatt eryth ro ugh
ove rvolt age When
chargin gusin gabat tery charge rwit h‐
out amaximu mchargin gvo ltag e, thebatt ery
or theve hicle electr 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 ging thebatt eryth ro ugh
ove rvolt age When
chargin gusin gabat tery charge rwit h‐
out amaximu mchargin gvo ltag e, thebatt ery
or theve hicle electr 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
A batt eryge ner ates hydrog en gasdur ing the
ch argin gpr oce ss.Ifth er eis ashor tcir cuit or
spar ksstar tto form ,th er eis adang erofthe
hy drog en gasigniting. #
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. #
When connectin gand disconn ectingth e
batt ery, yo umus tobse rveth edescr i‐
bed order forth ebatt eryclam ps. #
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
cables. #
Donotcon nect ordiscon nectthebat‐
te ry cla mp swhile theengine isrunning . 37
6
Brea kdo wnassista nce

&
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 at ther eis suf ficie ntventi‐
la tio ndu ring thech argin gpr oce ssand
dur ing star tin gassis tance. #
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 gasma ybe released. #
Alw aysth aw afroz en bat tery out firs t
bef orech argin git or per form ing star t‐
ing assis tance. 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 tact with 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. Br
ea kdo wnassista nce 37
7

Obser
vetheadditional follo wing pointsdur ing
st ar tin gassis tance:
R Startin gassis tance maybe perfor med using
onl ybatt eries withanominal voltag 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 Re
quirement s:
R The vehicle issecur edwithth eelectr icpar k‐
ing brak e.
R Automatic trans mis sion :The trans mis sion
is in po sitio n005D.
R The igniti onand allel ectr icalcons umersar e
sw itchedof f.
R The hoodis op en. #
Foldcover1 upinthedir ect ion ofthe
ar row . #
Slide cover2 ofposi tiveclam p3 onthe
jum p-starting con nection point inthedir ec‐
tion ofthear row . #
Con nect posi tiveclam p3 onyour vehicle to
th epositiv epole ofthedonor batteryusing
th ejum per cable/c harging cable. Always
begin withpositiv eclam p3 onyour ow n
ve hicle firs t. 37
8
Brea kdo wnassista nce

#
Dur ing star ting assistance :st ar tth e
engine ofthedonor vehicle andrunat idle
spe ed. #
Connect theneg ativepole ofthedonor bat‐
te ry and grou nd point 4 ofyour ow nve hicle
by usin gth ejum per cable/c harging cable.
Begin withth edonor batteryfirs t. #
During star ting assistance :st ar tth e
engine ofyour ow nve hicle. #
Dur ing thech argin gpr oc ess :st ar tth e
ch argin gpr oce ss. #
Dur ing star ting assistance :le tth eengines
ru nfo rse veralmin utes. #
Dur ing star ting assistance :bef oredis con‐
necting thejum per cable, switchon anelec‐
tr ical consumer inyour ow nve hicle, e.g.the
re ar wind owheat eror lighting.
When thest ar tin gassis tance/c harging proce ss
is com plet e: #
First,re mo vethejum per cable/c harging
cable from ground point 4and negative
pole ofthedonor battery, then from positiv e
clam p3 and positiv epole 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 cable/c harging
cable, closecover2 ofposi tiveclam p3. #
Closecover1.
Fu rther information canbeobt ained ataqu ali‐
fi ed specialis two rkshop. Re
plac ingthe 12Vbatt ery #
Obs erve theno teson the12 Vbatt ery
(/ page37 4).
Me rcedes-B enzrecomme ndsthat youha ve the
12 Vbatt eryre placed ataqu alif ied spec ialist
wo rkshop, e.g.atan aut hor ized Mercedes-Benz
Cent er.
Obser vethefo llo wing notesif yo uwa ntto
re place thebatt eryyo urself :
R Alw aysre place afa ulty battery wit habatt ery
whic hmee tsthespecif icvehicle requ ire‐
men ts.
The vehicle iseq uipped withan AGMtech nol ‐
ogy batter y(A bso rbentGlas sMa t)or alith ‐ ium-io
nbatt ery. Fu llve hicle functionality is
onl yguar anteed withan AGMbatt eryor lith‐
ium-ion battery. Fo rsaf etyre ason s,
Mer cedes-Ben zre comme ndsthat youon ly
use batteries whic hha ve been tested and
appr ovedfo ryo ur vehicle byMer cedes-Ben z.
R Carryove rde tach able parts,suc has vent
hos es,elbo wfitting orterm inal covers from
th ebatt erybeing replaced.
R Mak esur eth at theve nt hos eis alwa ys con‐
nect edtotheor iginal opening ontheside of
th ebatt ery.
Ins tallan yex istin gor supplied cellcaps.
Ot her wise, gases orbatt eryacid could
escape.
R Mak esur eth at detach able partsarere con‐
nect edinthesame way. To
w star ting ortowing away Pe
rm itted towing methods Mer
cede s-Ben zre comme ndstransp orting your
ve hicle inthecase ofabr eakdo wn,rath er than
to wing itaw ay. Br
ea kdo wnassista nce 37
9

Ins
tallin gth eto 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. #
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 . 38
4
Brea kdo wnassist anc e

Blo
wn fusesmus tbe replaced withfuses ofthe
same rating ,wh ich yo ucan recogni zeby the
colo rand fusera ting .The fuse rating sand fur‐
th er information tobe obser vedcan befound in
th efuse assignmen tdiagr am.
Fu se assignment diagram: onthefuse boxin
th etrunk (/page38 7).
* 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 (/page385)
R Fuse boxon thedr iver's side ofthecoc kpit
(/ page386)
R Fuse boxin thefront passeng erfoot we ll
(/ page386)
R Fuse boxin thetrunk ontheright-h andside
of theve hicle, when viewe din thedir ect ion
of tra vel(/ page38 7) 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
(/ page38 4). 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. Br
eakdo wnassis tance 38
5

Se
tting upthefo lding chock Pr
epa ring theve hicl efo ra wh eelch ang e Re
quirement s:
R The requ ired tire-c hang eto ol 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(/ page19 0). #
Switc hof 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. #
Remo vethehub caps ifneces sary
(/ page41 3). #
Raise theve hicle (/page41 4). Re
mo ving and inst alli ng hub caps Re
quirement s: R
The vehicle isprepar edfora whee lch ang e
(/ page41 3).
Plas tichub 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 .
Alum inum hubcap Wheels
andtires 41
3

#
Toremo ve:po sitio nsoc ket2 onhubcap
1.
% The socketcan befound inthetir e-c hang e
to ol kit. #
Position wheel wrenc h3 onsoc ket2. #
Usingwheelwr enc h3, turnhu bcap 1
cou nter-clo ckwise andremo veit. #
Toins tall: posit ionhub cap1and turnunt il
it is com pletely flush withth ewheel. #
Position socket2 onhubcap 1. #
Attach wheel wrenc h3 tosoc ket2 and
tig hten thehub capclockwise.
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(/ page41 3). R
Thehub capsha ve been remo ved
( / pag e41 3).
Im po rtant 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. 41
4
Wheels andtires