engine MERCEDES-BENZ C-CLASS SEDAN 2020 Workshop Manual

#
Slowly slide oildi ps tic k1 intoth eguide
tube tothestop, and take itout again afte r
appr oximat elyth re esecon ds.
R Oilleve lis cor rect:oil leve lis be tween 2
and 3.
R Oilleve lto olow: oil leve lis at 3 or
belo w.
R Oilleve lto ohigh: oilleve lis abo ve2 . #
Ifth eoil leve lis toolow, add 1.1 US qt
(1 liter) ofengine oil. #
Ifth eoil leve lis toohigh, drain offexc ess
engine oil.Consult aqu alif ied spec ialist
wo rkshop.
Chec kingtheengine oilleve lusing theon-
boar dcom puter
Re quirement s
The engin emus tha ve an oilleve lsen sor.If no t,
th eengine oilleve lcan becheckedonl ywit hth e
oil dips tick(/ page358).
The engine oilleve lis de term ined during drivin g.
De term inin gth eengine oilleve lcan take up to
30 minut eswit hanor mal driving style and even
long erwit han act ive dr ivin gst yle. In
order torecei veare sult asquickl yas possi‐
ble:
R warm uptheengine
R parkth eve hicle onaleve lsur face
R leave theengine running atidle spe ed
On-bo ardcom puter:
4 Service5
Engine OilLeve l
Yo uwill see oneof thefo llo wing mess ages on
th emultifunc tiondispla y:
R Measuring Engine OilLevel.. .:measur ement
of theoil leve lis no tye tpo ssi ble. #
Repeat there qu estaf te ra maximu mof
30 minut esdriving.
R Engine OilLevel OKand thebar displa yfo r
indic atingth eoil leve lon themultifunc tion
displa yis green and isbe tween "min" and
"max": theoil leve lis cor rect.
R Engine OilLeve lAdd 1.0land thebar displa y
fo rindica tingtheoil leve lon themultifunc ‐
tion displa yis orang eand isbelo w"min": #
Add1.1 US qt(1l)of engine oil. R
Red uce Engine OilLevel andthebar displa y
fo rindica tingtheoil leve lon themultifunc ‐
tion displa yis orang eand isabo ve"max ": #
Drain offan yex cess engineoilthat has been
added. Todo so, con sult aqu alif ied spec ialist
wo rkshop.
R For Engine OilLevel Switch Ignition On: #
Switc hon theignition tocheckth eengine oil
le ve l.
R Engine OilLeve lSyst emInoperat ive:sensor
fa ulty ornotins erted. #
Consult aqu alif ied spec ialistwo rkshop.
R Engine OilLevel System Currently Unavail.: #
Close thehood.
Ad ding engine oil &
WARNIN GRisk ofburnsfrom hotcom‐
ponent partsintheengine compartmen t
Cer tain com pone ntsin theengine compart‐
ment canbevery hot,e.g. theengine ,th e
ra diat orand partsof theex haus tsy stem. Maint
enanc eand care359

#
Allow theengine tocool down and only
to uc hco mp onent partsdescr ibedin
th efo llo wing. &
WARNIN GRisk offire and injuryfrom
eng ineoil
If eng ineoilcom esintocon tact with hot
com ponent partsintheengine compart‐
ment ,it ma yignit e. #
Mak esur eth at no eng ineoilisspille d
ne xt to thefiller open ing. #
Allo wtheengine tocool offand thor‐
oughl yclean theengine oilfrom com po‐
nen tpar tsbef orest ar tin gth eve hicle. *
NO
TEEngi nedama gecau sed byan
inc orrect oil filt er ,inc orrect oil oraddi‐
tiv es #
Donotus eengi neoilsor oil filt er s
whic hdo notcor respond tothespecif i‐
cation sex plicitl ypr escr ibed forth e
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. #
Followtheins truction sin theser vice
int erva ldispla yre ga rding theoil
ch ang e. *
NO
TEDama gecau sed byaddin gto o
muc hengine oil To
omuc hengine oilcan damag eth eengine
or thecat alytic converter . #
Have excess engineoilremo vedat a
qu alif ied spec ialistwo rkshop. #
Turn cap 1cou nter-cloc kwiseand remo ve
it. #
Addengin eoil. #
Replace cap1and turnit cloc kwise asfar
as itwill go. #
Chec kth eoil leve lag ain (/ page358 ). 360
Maintenanceand care

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 andcare36
1

#
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
(/ page434). 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. 362
Maintenance andcare

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 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-start connec‐
tion pointintheengine compartmen t. Br
eakdo wnassis tance 38
1

*
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 . &
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. 38
2
Brea kdo wnassist anc e

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.
Plug-in hybrid: besur eto obser vetheno tesin
th eSupplement .Ot her wise, youma yfa ilto rec‐
ogni zedangers.
Al lve hicl 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 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 missi on
is in po sitio n005D.
R The igniti onand allel ectr icalcons umersar e
sw itchedof f.
R The hoodis op en. Br
ea kdo wnassist anc e383

#
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. #
During 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‐ 38
4
Breakdo wnassis tance

*
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 . Blo
wn fuse smu stbe 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 (/page392).
* 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. 390
Breakdo wnassis tance

R
Allelectr icalconsu mersar esw itched off.
R The igniti onissw itched off.
The electr icalfu ses arelocat edinvarious fuse
bo xes:
R Fuse boxin theengine compartmen ton the
dr iver's side (/page39 1)
R Fuse boxon thedr iver's side ofthecoc kpit
(/ page392)
R Fuse boxin thefront passeng erfoot we ll
(/ page392)
R Fuse boxin thetrunk ontheright- hand side
of theve hicle, when viewe din thedir ect ion
of tra vel(/ page392 ) 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
(/ page390). 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 clip2 oncover1 aqu arter-tur nto
th elef t. #
Foldcover1 upinthedir ect ion ofthe
ar row . Br
ea kdo wnassista nce 39
1