2021 MERCEDES-BENZ A-CLASS SEDAN Owner's Manual

No
teson noise orunusua lhand lingcharac‐
te rist ics
Mak esur eth er ear eno vibr ations, noisesor
unusual handling charact eristic swhen theve hi‐
cle isin mo tion. Thismayindicat eth at the
wheels ortires aredamag ed.Hidde ntir edam‐
ag ecould alsobecausin gth eunusual handling
ch aract eristic s.
If yo ususp ectthat atir eis malf unctionin g,
re duce your spee dimm ediat elyand have the
tir es and wheelsch eckedat aqu alif ied spec ialist
wo rkshop. No
teson regular lyinspect ingwheels and
tir es &
WARNIN GRisk ofinju rythro ugh dam‐
ag ed tires
Dam aged tires can caus etir epr ess ureloss . #
Chec kth etir es regular lyforsigns of
dama geand replace anydamag edtires
immediat ely. &
WARNIN GRisk ofhydroplaning dueto
insuf ficie nttiretrea d
Insu fficien ttir etread willresult inreduced
tir egr ip.
In hea vyrain or slush therisk ofhydroplaning
is incr eased, inpar ticular wherespeed isno t
adap tedto suit thecon ditions . #
Thus, yousho uld regular lych eckth e
tr ea dde pthand thecon dition ofthe
tr ea dacr oss theent ire widt hof all tires.
Minimum tread depthfor:
R Summ ertires: 00CEin(3 mm)
R M+S tires: 00CFin (4mm) #
Forsaf etyre ason s,replace thetir es
bef oreth eleg ally -prescr ibed limit for
th eminimum tread depthisreac hed. Car
ryout thefo llo wing checks on allwheels reg‐
ular ly,at leas tonce amont hor as requ ired, for
ex am ple, prior toalon gjo ur ne yor drivin gof f-
ro ad:
R Chec kth etir epr essur e(/ page288). R
Visual lyinspect wheelsandtires fordama ge.
R Chec kth eva lve caps.
R Visual checkof thetir etread depthand the
tir econt actsurface across theent ire widt h.
The minimum tread depthforsummer tires is
00CE in(3 mm) andforwint ertires 00CF in
(4 mm). Six
mar ks1 showwher eth ebar indicat ors
(ar row )ar eint egr ated intoth etir etread. They
ar evisible onceatir etread depthofappr ox‐
imat ely00CD in(1.6 mm) hasbeen reac hed. Whee
lsand tires 28
7

No
teson sno wch ains &
WARNIN GRisk ofacci dent dueto inc or‐
re ct sno wch ain fitting
If yo ufit sno wch ains tothere ar wheels ,th e
sno wch ains maygr ind agains tth eve hicle
body orchassis components.
This couldcaus edamag eto theve hicle or
th etir es. #
Neverfit sno wch ains tothere ar
wheels . #
Alw aysfit sno wch ains tothefront
wheels inpair s. *
NO
TEDama getocom pone ntsofthe
ve hicle body orchassis duetomount ed
sno wch ains If
yo umoun tsn ow chains tothefront wheels
of 4MA TICvehicles, youma ydamag eco mp o‐
nent sof theve hicle body orchassis . #
Onlymount snowch ains tothere ar
wheels of4MA TICvehicles. *
NO
TEDama getothewheel trim from
mount edsno wch ains If
sn ow chains aremoun tedto steel wheels,
th ewheel trims can bedamag ed. #
Remo vethewheel trims ofsteel wheels
bef oremount ingsnowch ains . Obse
rveth efo llo wing noteswhen usingsnow
ch ains :
R Snow chains areon lype rm issible forcer tain
wheel/t ire com binat ions.Yo ucan obtain
inf ormat ionabout this from anaut hor ized
Mer cedes -Benz Cent er.
R Forsaf etyre ason s,on lyuse snow chains that
ha ve been specif icallyapproved foryo ur
ve hicle byMer cedes-Ben z,or sno wch ains
wit hth esame qualit yst andar d.
R Ifsn ow chains areins talled, themaximum
per missible speedis30 mph(50 km/h).
R Vehicl eswith Activ ePa rking Assis t:Do
no tuse ActivePa rking Assistwhen snow
ch ains areins talled. %
Youcan deac tivateES P®
to pull away
( / pag e15 5).Thi sal lo ws thewheels to
spin, achie ving anincr eased driving forc e. Ti
re pres sur e No
teson tirepr essur e &
WARNIN GRisk ofacci dent dueto insuf ‐
fi cie ntor excess ive tir epr ess ure
Ti re swit heit her toolow or toohigh apr es‐
sur epr esent thefo llo wing hazar ds:
R thetir es could burst
R thetir es could wearexcess ively and /or
une venly
R thedr iving charact eristic sas wellas
st eer ing and braking charact eristic sma y
be severely im pa ired #
Observeth ere comme ndedtirepr es‐
su resand checkth etir epr essur eof all
tir es including thespar ewheel:
R mont hly 288
Wheels andtires

R
ifalt ering theload ontheve hicle
R prior tolong journeys
R ifth eoper ating conditions chang e,for
ex am ple when drivin gof f-ro ad #
Adjus tth etir epr essur ewher eneces ‐
sar y. Ti
re pressur ewhic his toohigh ortoolow can:
R Shor tenth eser vice life of thetir es.
R Cause increased tiredamag e.
R Adversely affect drivi ng charact eristic sand
th us drivin gsaf ety, e.g. due tohydroplaning. &
WARNIN GRisk ofacci dent dueto too
lo w atir epr essur e
Ti re swit hpr essur eth at istoolow can over‐
heat andburstas acon sequenc e.
In addit ion,th ey also sufferfr om irre gular
we ar,whic hcan significan tly im pair thebr ak‐
ing proper tiesand thehandling charact eris‐
tic s. #
Avoid excessiv elylow tirepr essur e. Ti
re pressur ewhic his toolow can cause:
R Tire faults asare sult ofoverheating
R Impair edhandling charact eristic s
R Irre gular wear
R Incr eased fuelconsum ption &
WARNIN GRisk ofacci dent dueto too
high atir epr essur e
Ti re swit hexc essiv elyhigh pressur ecan
bur st.
In addi tion, they also sufferfr om irre gular
we ar,whic hcan significan tly im pair thebr ak‐
ing proper tiesand thehandling charact eris‐
tic s. #
Avoid excessiv elyhigh tirepr essur es. Ti
re pressur ewhic his toohigh cancause:
R Increased brakin gdis tance
R Impaired handl ing charact eristic s
R Irre gular wear
R Impair eddrivin gcom fort
R Sus ceptibility to damag e &
WARNIN GRisk ofacci dent dueto repea‐
te dpr essur edr op inthetir es
The wheels, valves ortires could bedam‐
ag ed.
To olow atir epr essur ecan lead tothetir es
bur sting. #
Examine thetir es forfo re ign obje cts. #
Chec kwhe ther thetir ehas apunct ure
or theva lve has aleak . #
Ifyo uar eunab leto rectify thedamag e,
con tact aqu alif ied spec ialistwo rkshop. Yo
ucan find spe cifica tions forth etir epr essur e
fo rth eve hicle's fact or y-ins talled tires on thefo l‐
lo wing labels:
R Tire and Loadi ngInfo rm atio nplacar don the
B‑pil larof your vehicle (/page295).
R Tire pressur eta ble ontheinside ofthefuel
fi ller flap (/ page29 0).
Obse rveth emaximum tirepr essur e
(/ page30 1). Wheels
andtires 289

Use
asuit able pressur ega ug eto checkth etir e
pr essur e.The outerappear anceofatir edoes
no tper mit anyre liable conclusion aboutthetir e
pr essur e.
Onl ycor rect tirepr ess urewhe nth etir es are
cold. Condition sfo rcold tires:
R The vehicle hasbeen parkedwit hth etir es
out ofdir ect sunlight forat lea stthre ehour s.
R The vehicle hastrave led less than 1mile
(1 .6 km ).
The vehicle's tires heat upwhen driving. Asthe
te mp eratur eof thetir es incr eases, sotoodoes
th etir epr essur e.
Ve hicl eswith tirepr ess uremonit oring sys‐
te m: Youcan also seethetir epr essur ein the
dr iver's displa y.
The tirepr essur ere comme ndedforincr ease d
loa d/spee din thetir epr essur eta ble can affect
th eride comf ort. &
WARNIN GRisk ofacci dent dueto
uns uitable accessories ontireva lves
If yo umoun tuns uitable accessories onto tire
va lves, thetir eva lves ma ybe ove rloaded and
malfunct ion,whic hcan cause tirepr essur e
loss. #
Onlyscr ew standar dva lve caps orvalve
cap sspe cifica llyapprove dby
Mer cedes-Ben zfo ryo ur vehicle onto
th etir eva lve. Ti
re pres sur etab le The
tirepr ess ureta ble ison theinside ofthe
fuel filler flap.
% The datasho wnintheimag esisexam ple
dat a. If
on eor mor etir esiz es prece deatir epr essur e,
th efo llo wing tirepr essur einf ormatio nis onl y
va lid forth ose tiresizes andtheir respectiv e
load condition.
The load conditions "partially laden" and"fully
laden" aredef ined intheta ble fordif fere nt num ‐
be rs of passeng ersand amounts oflugg age. The
actual number ofseats maydif ferfr om this. 290
Wheels andtires

Some
tirepr ess ureta bles onlysho wtherim
diame terins tead ofthecom pletetiresize, e.g.
R1 8.The rim dia me teris par tof thetir esize and
can befound onthetir eside wall(/ page302 ).
R Tire and Loadi ngInfo rm atio nplacar d
(/ page29 5)
R Max imum tirepr essur e(/ page30 1) Chec
kingtirepr essu resmanu ally #
Read thetir epr essur efo rth ecur rent operat‐
ing cond itions from theTire and Loadi ng
In fo rm atio nplacar dor thetir epr essur e
ta ble. Obser vetheno teson tirepr essur e. #
Remo vetheva lve cap ofthetir eto be
ch ecked. #
Press thetir epr essur ega ug esec urelyon to
th eva lve. #
Read thetir epr essur e. #
Ifth etir epr essur eis lowe rth an there com‐
mend edvalue, increase thetir epr essur eto
th ere comme ndedvalue. #
Ifth etir epr essur eis higher than there com‐
mend edvalue, release air.To do so, press
do wn theme talpin intheva lve, e.g. using
th etip ofapen, forex am ple. Then checkth e
tir epr es su re again usin gth etir epr essur e
ga ug e. #
Screw theva lve cap ontoth eva lve.
Fu rther relat ed subje cts:
R Noteson tirepr essur e(/ page288) R
Tire pressur eta ble (/ page290 )
R Tire and Loadi ngInfo rm atio nplacar d
(/ page29 5) Ti
re pres sur emoni toring system Fu
nction ofthetir epr essur emoni toring sys‐
te m &
DANG ER Risk ofacc iden tdue toinc or‐
re ct tirepr ess ure
Eac htir e, incl uding thespar e(if prov ided),
should becheckedmont hlywhen coldand
th en inflated totheinf lation pressur ere com‐
mend edbytheve hicle manuf actureron the
ve hicle placar dor tireinf lation pressur e
label .(If your vehicle hastires ofadif fere nt
si ze than thesize indicat edon theve hicle
placar dor tireinf lation pressur elabel ,yo u
should determ ine thepr oper tireinf lation
pr essur efo rth ese tires.)
As anadded safetyfe atur e,your vehicle has
been equipped withatir epr essur emonit or‐
ing system (TPMS) that illumin ates alow tire Whee
lsand tires 29
1

pr
essur ete lltale when oneormor eof your
tir es issign ifican tly und erinf lated. Accor d‐
ing ly,if th elow tirepr essur ete lltale illumi‐
nat es, yousho uld stop and checkyo ur tires
as soo nas poss ible, andinflateth em tothe
pr oper pressur e.Driving onasignif icantly
under inflated tirecauses thetir eto ove rheat
and canlead totirefa ilur e.Un der inflation
also reduces fuelefficie ncy and tiretrea d
li fe ,and mayaf fect theve hicle's handling
and stopping ability.Please note that the
TPMS isno ta subs titutefo rpr oper tiremain‐
te nance ,and itis thedr iver's responsibili ty
to maint aincorrect tirepr ess ure, eve nif
und erinf latio nha sno tre ac hed theleve lto
tr ig ge rill umina tionoftheTPMS low tirepr es‐
sur ete lltale.
Yo ur vehicle hasalso been equipped witha
TPMS malfunction indicatortoindic atewhen
th esy stem isno toper ating proper ly.The
TPMS malfunct ionindicat oriscombin edwith
th elow tirepr essur ete lltale. When thesy s‐
te m detects amal functi on,theindicat or
lam pwill flash forapp roxima tely amin ute and
then remain continuously illumina ted.
This sequence willcontinue upon subseq uent
ve hicle star t-ups aslon gas themalfunct ion
ex ists.
When themalfunct ionindicat orisillumina‐
te d, thesy stem mayno tbe able todetect or
sig nal low tirepr ess ureas intende d.TPM S
mal functi onsmayoccu rfo ra va riet yof rea‐
son s,inc ludin gth eins tallation ofinc om pati‐
ble replacemen tor alternat etir es orwheels
on theve hicle that prev ent theTPMS from
func tioningproper ly.
Alw aysch eckth eTPMS malfunct iontelltale
af te rre placing oneormor etir es orwheels
on your vehicle toensur eth at there place‐
ment oralternat etir es and wheels allowthe
TPMS tocontinu eto function proper ly. The
system checks thetir epr essur eand thetir e
te mp eratur eof thetir es installed ontheve hicle
by means ofatir epr essu resensor .
The tirepr essur eand thetir ete mp eratur e
appear intheon- boar dcom puter(/ page293). If
th er eis asubs tantia lpr ess ureloss orifth e
tir ete mp eratur eis exc essiv e,youwill bewarned
in thefo llo wing ways:
R viadisp lay messa ges(/ page37 2).
R via th e0077 warning lam pin theins trument
clus ter(/ page392)
The tirepr essu remonit oring system isonl yan
aid. Itis thedr iver's responsibili tyto setth etir e
pr essur eto there comme ndedcoldtirepr ess ure
su itab leforth eoper ating situation .
In mos tcases, thetir epr essur emonit oring sys‐
te m wil lau tomatical lyupdat eth ene wrefere nce
va lues afte ryo uha ve chang edthetir epr essur e.
Yo ucan ,ho we ver,also updat eth ere fere nce val‐
ues byrestar tin gth etir epr essur emonit oring
sy stem manually (/page392).
Sy stem limit s
The system maybe impair edorma yno tfunc tion
par ticular lyin thefo llo wing situat ions:
R The tirepr essur ehas been setinc orrectl y
R Sud den press urelos scau sed byafo re ign
obje ctpene tratin gth etir e, forex am ple 292
Wheelsand tires

R
Ther eis amalfunct ioncaused byano ther
ra dio signal source
Chec kingthetir epr essur ewit hth etir epr es‐
sur emoni toring system
Re quirement s:
R The ignit ionisswitc hedon.
On- boar dcom puter:
4 Service 5
Tires
One ofthefo llo wing displa ysappear s:
R Cur rent tirepr ess ureand tirete mp eratur eof
th eindividual wheels: R
Tire pressure willbedisplayed afterdriving a
few minutes
R Tire Pressure MonitorAct ive: thete ac h-in
pr oce ssofthesy stem isno tye tcomple te.
The tirepr essur esarealr eady being moni‐
to re d. #
Com pareth etir epr essur ewit hth ere com‐
mend edtirepr ess urefo rth ecur rent operat‐
ing cond ition (/ page 290). Observeth e
no teson tirete mp eratur e(/ page288).
% The values displa yedin theon- boar dcom‐
put erma yde viat efrom those ofthetir e
pr essur ega ug eas they referto sea leve l.At
high elevatio ns, thetir epr essur eva lue indi‐
cat edbyapr essur ega ug ear ehigh erthan
th ose shownbytheon- boar dcom puter.In
th is case, donotre duce thetir epr essur e.
Re star ting thetir epr essur emoni toring sys‐
te m
Re quirement s:
R The recomme ndedtirepr ess ureis cor rectl y
se tfo rth ere spectiv eoper ating status onall
of thewheels (/page288). Re
star tth etir epr essur emonit oring system in
th efo llo wing situat ions:
R The tirepr essur ehas chang ed.
R The wheels ortires have been chang edor
ne wlyins talled.
On- boar dcom puter:
4 Service 5
Tires #
Swipe down wardson Touc hCon trol on the
lef t-hand sideofthesteer ing wheel.
The Use Current Pressures asNew Refer-
ence Values messag eis sho wninthemulti‐
func tion displa y. #
Torestar t,pr ess Touc hCon trol on thelef t-
hand sideofthesteer ing wheel.
The Tire Press. MonitorRestart edmessag eis
sho wninthemultifunc tiondispla y.
Cur rent wa rning mess ages aredele tedand
th eye llo w0077 warning lam pgoes out.
Af teryo uha ve been driving fora fe w
minut es,thesy stem checks whe ther thecur‐
re nt tirepr ess ures arewi thin thespecif ied
ra ng e. The current tirepr ess ures areth en
accep tedas refere nce values andmon itor ed. Wheels
andtires 293

Be
sureto also payatt ent ion tothefo llo wing
re lat ed topic:
R Noteson tirepr essur e(/ page288) Ti
re pres sur elo ss wa rning system Fu
nction ofthetir epr essur eloss warning
sy stem
The tirepr essur eloss warning system warnsth e
dr iver by means ofdisp lay messa geswhen ther e
is ase vere tirepr es su re loss.
Sy stem limit s
The system maybe impair edorma yno tfunc tion
par ticular lyin thefo llo wing situat ions:
R Incorrectly settir epr ess ure
R Sud den press urelos scau sed,fo rex am ple,
by afo re ign obje ctpene tratin gth etir e
R Steady pressur eloss inseveraltir es
The system has are strict ed ordel aye dfunc tion
par ticular lyin thefo llo wing situat ions:
R Poor ground condit ions,e.g.snowor gra vel
R Driving with sno wch ains R
When adoptingave ry spor tydriving style
wit hhigh corner ing speeds orsudden accel‐
er ation
R Drivin gwit hahigh load
The tirepr essur eloss warning system isonl yan
aid. Itis thedr iver's responsibili tyto setth etir e
pr essur eto there comme ndedcoldtirepr ess ure
su itab leforth eoper ating situation andtocheck
it.
Be sureto also obse rveth efo llo wing further
re lat ed subje cts:
R Noteson tirepr essur e(/ page288)
R Displa ymessag esabout thetir es
(/ page37 2)
Re star ting thetir epr essur eloss warning
sy stem
Re quirement s:
R The recomme ndedtirepr ess ureis cor rectl y
se tfo rth ere spectiv eoper ating status onall
wheels . Re
star tth etir epr essur eloss warning system in
th efo llo wing situat ions:
R The tirepr essur ehas chang ed.
R The wheels ortires have been chang edor
ne wlyins talled.
On- boar dcom puter:
4 Service 5
Tires #
Swipe down wardson Touc hCon trol on the
lef t-hand sideofthesteer ing wheel.
The Tire Pressure ControlSystem Active
Restart messageis sho wninthemultifunc ‐
tion displa y. #
Tobegin restar t,pr ess Touc hCon trol on the
lef t-hand sideofthesteer ing wheel.
The Tire Pressure NowOK?messag eis
sho wninthemultifunc tiondispla y. #
Select Yes. #
Toconf irm restar t,pr ess Touc hCon trol on
th elef t-hand sideofthesteer ing wheel.
The Run FlatIndic atorRestart edmessag eis
sho wninthemultifunc tiondispla y. 29
4
Wheels andtires