ignition MERCEDES-BENZ C CLASS 2021 Owner's Guide

R
freq uent operation inmount ainouste rrain or
on poor road sur faces
R whe nth eengine isoftenleft idling forlong
per iods
R oper ation inpar ticula rly dus tycond ition s
and /orif air -rec ircula tion mod eis freq uen tly
used
In these orsimilar operating conditions ,ha ve the
int erior airfilt er ,engin eair clean er,engin eoil
and oilfilt er etc. chang edmor efreq uent ly.The
tir es mus tbe checkedmor efreq uentl yif th e
ve hicle isoper ated under increased loads. Fur‐
th er information canbeobt ained ataqu alif ied
spec ialistwo rkshop. Batt
erydisconne ctionperiods The
ASSYSTPL US service interva ldispla ycan
calc ulateth eser vice duedateonl ywhen the
batt eryis con nected. #
Notedown theser vice duedatedispla yedon
th eins trument displaybef orediscon necting
th ebatt ery(/ page300). Engine
compartment Opening
andclosing thehood &
WARNIN GRisk ofacci dent dueto driv‐
ing withth ehood unlocked
The hood mayopen andblockyo ur vie w. #
Neverre lease thehood when driving. #
Beforeev erytrip, ensur eth at thehood
is loc ked. &
WARNIN GRisk ofacci dent andinjury
when openingand closingthehood
The hood maysuddenl ydr op intoth eend
position .
Ther eis arisk ofinjur yfo ran yone inthe
hood's rang eof mo vement. #
Donotopen orclose thehood ifth er e
is aper son inthehood's rang eof mo ve‐
ment. &
WARNIN GRisk ofburnswhen opening
th ehood
If yo uopen thehood when theengine has
ove rheat edorwhen ther eis afire inthe
engine compartmen t,th efo llo wing situat ions
ma yocc ur:
R Youco uld come intoco ntact withho t
ga ses.
R Youco uld come intoco ntact withot her
ho t,escaping operating fluids. #
Beforeopen ingthehood, allowthe
ove rheat edengine tocool down. #
Intheeve ntofafire intheengine com‐
par tmen t,ke ep thehood closed and
call thefire ser vice. &
WARNIN GRisk ofinju rydue tomo ving
par ts
Com ponents intheengine compartmen tma y
con tinue running orstar tup sudden ly,ev en if
th eignition isswitc hedoff. Maint
enanc eand care30
1

Mak
esur eof thefo llo wing beforeper form ing
ta sk sin theengine compartmen t: #
Swi tchth eignition off. #
Neverre ac hint oth edang erzon esur‐
ro und ingmovingco mp onent s,e.g. the
ro tatio nar ea ofthefa n. #
Remo vejewe leryand watche s. #
Keep items ofclo thing and hair away
fr om moving parts. &
WARNIN GRisk ofinju ryfrom touc hin g
co mp onent sunder voltag e
The ignit ionsystem and thefuel injec tion
sy stem workund erhigh voltag e. Youco uld
re cei vean elec tric shoc k. #
Neverto uc hco mp onent sof theignition
sy stem orthefuel injec tionsystem
when theignition isswitc hedon. &
WARNIN GRisk ofburnsfrom hotcom‐
ponent partsintheengine compartmen t
Cer tain com pone ntpar tsintheengine com‐
par tmen tcan bevery hot,e.g. theengine,
th ecooler andpartsof theex haus tsy stem. #
Allo wtheengine tocool down and only
to uc hco mp onent partsdescr ibedin
th efo llo wing. &
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
tr apped bythewiper linkage. #
Alw aysswitc hof fth ewindshield wipers
and ignition beforeopening theengine
hood. Opening
thehood #
Torelease thehood, pullonhandle 1. 302
Maintenanc eand care

#
Slowly slide oildi ps tic k1 intoth eguide
tube tothestop, and pullitout again afte r
about thre 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:
R The engin ehas anoilleve lsen sor.If no t,th e
engine oilleve lcan becheckedonl ywit hth e
oil dips tick(/ page303).
R The engine hasbeen warmed up.
R The vehicle ispar kedon aleve lsur face.
R The engineisrunning atidle spe ed. R
The hoodis clo sed .
The engineoille ve 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.
On- boar dcom puter:
4 Service5
Engine OilLevel
One ofthefo llo wing mess ages will appear 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 es'driving.
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:The oil
le ve lsen sor ismalfun ctionin gor notcon nec‐
te d. #
Consult aqu alif ied spec ialistwo rkshop.
R Engine OilLevel System Currently Unavail. #
Close thehood. 30
4
Maint enanc eand care

%
Have wo rkor repair sto decor ativefo ils car‐
ri ed out ataqu alif ied spec ialistwo rkshop,
e.g. atan aut hor ized Mercedes-Benz Center. No
teson car eof vehicl epar ts &
WARNIN GRisk ofentr apment ifth e
winds hieldwiper sar eswit ched on while
th ewindshield isbeing cleaned
If th ewindshield wipersar ese tin mo tion
while youar ecle anin gth ewindshield or
wiper blades, youcan betrapped bythe
wiper arm. #
Alw aysswitc hof fth ewindshield wipers
and theignition beforecleanin gth e
winds hieldorwiper blades. &
WARNIN GRisk ofburnsfrom theta il‐
pipe andtailpipe trims
The exhaus tta ilpipe andtailpipe trims can
becom eve ry hot.Ifyo uco me intoco ntact
wit hth ese partsof theve hicle, youco uld
bur nyo urself . #
Alw aysbe par ticular lycareful arou nd
th eta ilpipe andtheta ilpipe trims and
super visechildr enespec iallycloselyin
th is area. #
Allo wvehicle partsto cool down before
to uc hin gth em. To
avo iddamag eto theve hicle, observethe
no teson cleaning andcareof thefo llo wing vehi‐
cle parts:
Wheels andrims
R Use waterand acid-free alloy wheel cleaners.
R Donotuse acidic alloywheel cleanersto
re mo vebrak edus t.This could damag ewheel
bolts andbrak ecom ponen ts.
R Toavo idcor rosion ofthebr ak ediscs and
br ak epads, drive th eve hicle fora fe w
minut esafte rclea ning beforepar king it.The
br ak ediscs andbrak epa dswarm upand dry
out . Wi
ndo ws
R Clean thewindo wsinsid eand outs idewitha
dam pclo thand withacle anin gag ent recom‐
mend edforMer cedes-Benz.
R Donotuse dryclo thsor abr asiv eor sol vent-
ba sed cleani ng agents tocle an theinside of
windo ws.
Wi per blades
R Movethewiper arms intoth ere placemen t
position (/page12 0).
R With thewiper arms folded out,clean the
wiper blades withadam pclo th.
R Donotcle an thewiper blades tooof ten.
Ex terior light ing
R Clean thelenses withawe tsp ong eand mild
cle ani ng agent, e.g.car shampoo.
R Onlyuse cleaning agents orcleaning cloths
th at aresuit able forpla stic lens es.
Sensor s
R Clean thesensor sin thefront and rear
bum perswit hasof tclo thand carsham poo
(/ page15 8). Mai
ntenance andcare 31
1

#
Push theplug ofhose 5intoflang e6 of
tir esealan tbo ttle 1 untilth eplug engages. #
Place tiresealant bottle 1 head down wards
int ore cess 2ofthetir einf lation compres‐
sor . #
Remo vethecap from valve 7 onthefa ulty
tir e. #
Screw filling hose 8ontova lve 7. #
Insertplug 4intoa12 Vsoc ketin your
ve hicle. #
Switc hon theignition . #
Press onand offswitc h3 onthetir einf la‐
tion compressor .
The tireinf lation compressor isswitc hedon.
The tireis inf lated. First,tir esealant ispum‐
ped intoth etir e. The pressur ema ybr ief ly
ri se toappr oximat ely500 kPa(5 bar/7 3psi).
Do notswitc hof fth etir einflat ioncom pres‐
sor during this pha se! #
Letth etir einf lation compressor runfo ra
maximu mof tenminu tes.
The tireshould then have attaine datir e
pr essur eof at leas t20 0kP a(2. 0bar/
29 psi).
If tir esealan tleak sout ,mak esur eyo ucle an the
af fect ed area asquickl yas possible .It is prefer a‐
ble touse clean water.
If yo uge ttir ese alant onyour clo thing, have it
clean edassoon aspossible withper chlor oethy‐
len e. If,
afte rte nminut es,atir epr essur eof
200 kPa(2.0 bar/29 psi)hasnotbeen
attained: #
Switc hof fth etir einf lation compressor . #
Unscr ew thefilling hose from theva lve of the
fa ulty tire.
Pleas eno te that tiresealan tma yleak outwhen
uns crew ing thefilling hose. #
Very slo wlydr ive fo rw ards orreve rseappr ox‐
imat ely33 ft(10 m). #
Pum pup thetir eag ain.
Af tera maximu mof tenminu testh etir e
pr essur emus tbe atleas t200 kPa(2.0 bar/
29 psi). &
WARNIN GRisk ofacci dent dueto the
specif iedtirepr essur eno tbeing attained
If th eminimum tirepr essur eis no tre ac hed
af te rth especif iedtime, thetir eis toobadl y
damag ed.The tiresealant cannotrepair the
tir ein this ins tance.
The braki ng and drivi ng charact eristic sma y
be great lyim pair ed. Br
eakdo wnassis tance 31
9

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. #
Foldcover1 upinthedir ect ion ofthe
ar row . Br
ea kdo wnassista nce 32
5

*
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 (/page334).
* 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 (/page332)
R Fuse boxon thedr iver's side ofthecoc kpit
(/ page333)
R Fuse boxin thefront passeng erfoot we ll
(/ page334) R
Fuse boxin thetrunk ontheright-h andside
of theve hicle, when viewe din thedir ect ion
of tra vel(/ page334 ) 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
(/ page33 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. 332
Breakdo wnassis tance

+
ENV
IRONM ENTALNOTEEnvironme ntal
po lluti on dueto disposing ofoper ating
fl uids inano n-en viron men tally responsi‐
ble manner Oper
ating fluids include thefo llo wing:
R fuels
R exhaus tga saf te rtre atm entaddit ives, e.g.
DE F
R lubr ican ts
In cor rect dispo salofope rating fluids can
caus eco nsider able damag eto theen viron‐
ment . #
Dispose ofoper ating fluids inan envi‐
ro nment ally responsible manner. Oper
ating fluids include thefo llo wing:
R Fuels
R Lubricant s
R Coolant
R Brak efluid
R Windsh ield wa sher fluid R
Climat eco ntro lsy stem refrig er ant
Only useprodu ctsapp rove dby Mer cedes-Ben z.
Damag ecaused bytheuse ofproducts that have
no tbe en approve dis no tco veredby the
Mer cedes-Ben zwa rrant yor good willgestur es.
The oper atingfluids approvedby Mer cedes-Ben z
can beidentif iedbythefo llo wing inscript ions on
th econ tainer :
R MB- Freig abe (e.g. MB-Freig abe 229. 51)
R MB- Appr oval (e. g.MB- Approva l229 .51)
Fu rther information onappr ovedoper ating flu‐
ids:
R intheMer cedes- BenzSpecif ication sfo r
Oper ating Fluids byent ering thedesignation
- athtt ps:/ /bevo.mercedes-b enz.com
- intheMer cedes- BenzBeVoapp
R ataqu alif ied spec ialistwo rkshop &
WARNIN GRisk offire or explosion from
fuel
Fu els arehighly flammab le. #
Fire,open flames ,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‐ 37
0
Tech nica lda ta

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
(/ page36 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 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 8).
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 engineoutput and
incr ease fuelconsum ption.
Ne verre fuel using gasoline withan eve nlowe r
RO N. Te
ch nica lda ta 37
1

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
Hazard Warning Flashers
Malfunct ioning *T
hehazar dwa rning lam pswitc his malfun ctionin g. #
Consult aqu alif ied spec ialistwo rkshop. Ve
hicl e Dis
playmessag es
Possible causes/conseq uencesand0050 0050
Solutions
0072 Vehicle ReadytoDrive
Switc hthe Ignit ionOff
Before Exiting *Y
ouarelea ving theve hicle when itis in are ady -to- dr ive st at e. #
When youlea vetheve hicle, switchof fth eignition ,secur eth eve hicle agains tro lling away and taketh eSmar t‐
Ke ywit hyo u. #
Ifyo udo notlea vetheve hicle, switchof fth eelectr icalconsumer s,e.g. theseat heating. Other wise, the12 V
batt eryma ydisc hargeand itwill then be possible tostar tth eve hicle onlywit hth eaid ofasecon dbatt ery
(s ta rting assis tance) .
Ù Stee ringMalfunctio n
Incre ased Phy sical Effor t
See Operator'sManua l *T
hepowe rst eer ing assis tance isma lfunctio ning. &
WARNIN GRisk ofan acci dent dueto altered steer ing charact eristic s
If th epo we rassi stanc eof thesteer ing fails par tiall yor com pletely,yo uwill need touse morefo rc eto steer . #
Ifsaf esteer ing ispossible, drive on car efully . #
Visit orconsult aqu alif ied spec ialistwo rkshop immediat ely. 388
Displa ymessag esand warning/ indic ator lam ps