engine MERCEDES-BENZ C-CLASS SEDAN 2020 Repair Manual

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 9). #
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 9). #
Raise theve hicle (/page420). Re
mo ving and inst alli ng hub caps Re
quirement s: R
The vehicle isprepar edfora whee lch ang e
(/ page41 9).
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 .
Alum inum hubcap Wheels
andtires 41
9

#
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 9). R
Thehub capsha ve been remo ved
( / pag e41 9).
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. 420
Wheels andtires

The
follo wing canbeused intheve hicle without
re strictions :
R Two-w ayradios withamaximum transmis ‐
sion output ofup to100mW
R RFtransmi tter swit htransmi tter freq uenci es
in the380 -41 0MHz freq uency bandanda
maximu mtransmi ssionoutpu tof up to2W
(tr unk edradio system/T etra )
R Mobile phones (2G/3G/4G)
Ther ear eno restrictions whenpos itioning the
ant enn aon theoutside oftheve hicle forsome
wav ebands.
This applies tothefo llo wing wavebands:
R Trunk edradio system/T etra
R 70cm freq uency band
R 2G/3G /4G 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 Perm issible gros swe ight
2 Perm issible front axle load
3 Perm issible rear axle load
4 Paint code
5 VIN (vehicle identificat ion numb er) 428
Tech nica lda ta

Ve
hicle identif ication plate(Canada only)
1 Perm issible gros swe ight
2 Perm issible front axle load
3 Perm issible rear axle load
4 Paint code
5 VIN (vehicle identificat ion numb er)
The permissib legross vehicle weight ismade up
of theve hicle weight ,all vehicle occupants, the
fuel andtheload. Themaximum gross axle
we ight rating isthemaximum weight that can be
car ried on one axle (front orrear axle ). Ne
verexc eed theper missible gross vehicle
we ight orthemaximum gross axle weight rating
fo rth efront orrear axle .
VIN infront oftheright- 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 Te
ch nica lda ta 429

#
Donotsw allo w fuel or letit come into
cont actwith skin, 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 . Fu
el No
teson fuel grades forve hicl eswith gaso‐
line engines
Obser vetheno teson oper ating fluids
(/ page43 0).
* 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 unleade d
fuel.
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
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 (/ page15 9).
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 orarymeasur 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 engineper form anc e
and increase fuel consum ption.
Ne verre fuel using gasoline withan eve nlowe r
RO N. Te
ch nica lda ta 43
1

*
NO
TEPrema ture wearthro 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 andfill up as
soon aspossible withunleaded pre‐
mium grade gasoline. #
Donotdr ive at themaximum design
speed. #
Avoid sudden accelerationandengine
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 USAonly: athttp: //www .mbusa.com Inf
ormat iononaddit ives ingasoline
Obser vetheno teson oper ating fluids
(/ page43 0).
* 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 fuel
br and sth at have addit ives.
In som ecoun tries, 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,th efuel maybe mix ed
wit hth ecleanin gadditiv ere comme ndedby
Mer cedes-Ben z.Be sureto obser vetheno tes
and mixing ratio ssp eci fied on thecon tainer .
Ta nk cont entand fuel reser ve
The totalcapac ityofthefuel tank mayva ry,
dependin gon theve hicle equipment. 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
(/ page43 0). 432
Tech nica lda ta

*
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.
Fu rther information onengine oiland oilfilt er sis
av ailable atthefo llo wing locations:
R IntheMer cedes- BenzSpecif ication sfo r
Oper ating Fluids byent ering thedesignation :
- Athttp: //be vo.mer cedes-b enz.com
- IntheMer cedes- BenzBeVoapp R
ataqu alif ied spec ialistwo 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 . Capa
city Model
Capacity
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
(/ page43 0). &
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. Te
ch nica lda ta 433

Ha
ve thebr ak efluid regular lyreplaced ata
qu alif ied spec ialistwo rkshop.
Onl yuse brak efluid appr ovedby Mer cedes-Ben z
accor dingtoMB-F reigabe orMB- Appr oval 33 1.0.
Yo ucan obtain further information onbrak efluid
in thefo llo wing places:
R intheMer cedes- BenzSpecif ication sfo r
Oper ating Fluids
- athttp: //be vo.mercedes-b enz.com
- intheMer cedes- BenzBeVoApp
R ataqu alif ied spec ialistwo rkshop Cool
ant No
teson coolant
Obser vetheno teson oper ating fluids
(/ page43 0). &
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 #
Onlyad dcool 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 for
Oper ating Fluids 310.1
- Athttp: //be vo.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 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.
The propor tionofcor rosion inhibit or/antifr eeze
concen trat ein theengine cooling system should
be:
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)) 43
4
Tech nica lda ta

Coolant
capacit y Mod
el Capacity
All mode ls 9.5US qt(9.0liter s) No
teson windshield washer fluid Obser
vetheno teson oper ating fluids
(/ page43 0). &
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 teras 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 thewa sher fluid withth ewindshield washer
fl uid allyear round . Re
frig er ant No
teson refrig er ant
Obser vetheno teson oper ating fluids
(/ page43 0).
* NO
TEDama gedue toinc orrect refrig er‐
ant If
anon-appr ovedre frig er ant isuse d,thecli‐
mat econ trol system maybe damag ed. #
Onlyuse there frig er ant R‑134a *
NO
TEDama getotheclimat econ trol
sy stem due toinc orrect refrig er ant com‐
pr essor oil #
Onlyuse refrig er ant com pressor oilthat
has been approvedby Mer cedes-Ben z. Te
ch nica lda ta 435

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
NEVE Ruse are ar wa rdfacing child restra int onaseat protect edbyan ACTIVE AIRBAGinfront ofit,DE ATHor
SERIOU SINJU RYtotheCH ILD can occur . #
Stop theve hicle immediat elyinaccor dance withth etraf fic condi tions. #
Checkth est atus oftheaut omatic front passeng erairbag actuation (/page45). #
Ifneces sary,consu ltaqu alif ied spec ialistwo rkshop immediat ely.
Active BrakeAssi stFunc-
tio ns Curre ntly LimitedSee
Ope rator' sMa nua l *
Ve hicl eswith theDr iving Assistance Packag e:Ac tiveBr ak eAssi stwit hcr oss- traf fic functi on,Evasi ve Steer ing
Assis tor PRE‑S AFE®
PL US arete mp orarily una vailable oronl ypar tiall yav ailable.
Ve hicl eswithout theDr iving Assistance Packag e:Ac tiveBr ak eAssi stistemp orarily una vailable oronl ypar tiall y
av ailable.
The ambie ntcon dition sar eout side thesy stem limits (/page17 5). #
Drive on.
As soo nas theambient conditions arewit hin thesy stem limits, thesy stem will become available again. #
Ifth edispla ymessag edoes notdisappear ,st op theve hicle inaccor dance withth etra ffic con dition sand restar t
th eengine.
Act ive Brak eAssist Func-
tion sLimited SeeOpera-
tor' sManual *
Ve hicl eswith Drivin gAss istanc ePa ckag e:Ac tiveBr ak eAssi stwit hcr oss- traf fic functi on,Evasi ve Steer ing
Assis tor PRE‑S AFE®
PL US ismalfunct ioning.
Ve hicl eswithout Drivin gAss istanc ePa ckag e:Ac tiveBr ak eAssi stismalfun ctionin g. #
Consult aqu alif ied spec ialistwo rkshop. Displa
ymessag esand warning/ indic ator lam ps 453