tires MERCEDES-BENZ A-CLASS SEDAN 2021 Service Manual

%
Dep endingontheve hicle equipment, the
to ol bag maybe locat edatother positions in
th etrunk . The
tool bag cont ains:
R Jack
R Gloves
R Lugwr enc h
R Alignmen tbolt
R Folding choc k
R Ratche tfo rjac k Pr
epar ingtheve hicl efo ra wh eelch ang e Re
quirement s:
R The requ ired tire-c hang eto ol kit 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. #
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. #
Ifnec essar y,remo vethewheel trim/hub
caps (/page31 1). #
Raise theve hicle (/page31 2). Re
mo ving and inst alli ng thewheel trim/h ub
cap s Re
quirement s:
R The vehicle isprepar edfora whee lch ang e
(/ page31 1).
Whee ltr im
The wheeltrim covers thewheel boltsonvehi‐
cles withsteel wheels. Beforeunscr ewing the
wheel bolts,remo vethewheel trim. #
Toremo ve:us ing both hands, carefull yre ac h
int otw owheel trim open ingsand remo vethe
wheel trim. Wheels
andtires 31
1

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 #
Toremo ve:po sitio nsoc ket2 from thetir e-
ch ang eto ol kit onhub cap1. #
Position wheel wrenc h3 onsoc ket2. #
Usingwheelwr enc h3, turnhu bcap 1
cou nter-clo ckwise andremo veit. #
Toins tall: follo wtheins truction sabo vein
re ve rseor der .
% 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(/ page31 1).
R Thewh eeltr im sand hubcap sha ve been
re mo ved(/ page31 1).
Im po rtant noteson using thejac k:
R Use onlya ve hicle-specif icjac kth at has
been approved byMer 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. 31
2
Wheels andtires

R
Donotop en orclo seanydo orsor thetrunk
lid. #
Using thelug wrenc h,loosen thewheel bolts
on thewheel youwish tochang eby about
on efull turn.Do notuns crew thebolts com‐
ple tely. Po
sition ofjac ksuppor tpoints
* NO
TEMer cedes-AMG vehicles #
Obser vetheno tesin theSupplement .
Yo uco uld other wise failto recogni ze
da ngers. &
WARNIN GRisk ofinju ryfrom incor rect
pos itioning ofthejac k
If yo udo notposi tionth ejac kcor rectl yat
th eappr opriatejac king point oftheve hicle,
th ejac kcould tipwithth eve hicle raised. #
Onlyposit ionthejac kat theappr opri‐
at ejac king point oftheve hicle. The
base ofthejac kmus tbe position ed
ve rticall yunder thejac king point ofthe
ve hicle. *
NO
TEVehicle damag efrom thejac k If
yo udo notposi tionth ejac kcor rectl yat
th eappr opriatejac ksuppor tpoint ofthe
ve hicle, thejac kcould tipove rwit hth eve hi‐
cle raised. #
The jackis design edexclu sively for
jac king uptheve hicle atthejac ksup‐
por tpoints . #
Take thera tche tou tof thetir e-c hang eto ol
kit and place iton thehe xagon nutofthe
jac kso that theletter s"A UF" arevisible. Wheels
andtires 31
3

#
Position suppor t2 ofjac k4 onjacksup‐
por tpoint 1.
% Ifth er eis atot alloss ofpressur ein atir e, it
ma ybe poss iblethat thejac kcann otbe
position edatjac ksuppor tpoint 1.Inthis
case, unload theve hicle. #
Turn ratche t3 clockwise untilsuppor t2
sit scom pletely on jacksuppor tpoint 1and th
ebase ofthejac klies evenlyon the
gr ou nd . #
Turn ratche t3 unti lth etir eis raised amaxi‐
mum of1.2 in (3 cm) from thegr ound. #
Loosen andremo vethewheel (/page31 4). Re
mo ving awh eel Re
quirement s:
R The vehicle israised (/page31 2).
* NO
TEMer cedes-AMG vehicles #
Obser vetheno tesin theSupplement .
Yo uco uld other wise failto recogni ze
da ngers. Whe
nch ang ingawheel, avoidapplyin gan yfo rc e
to thebr ak ediscs, asthis could impair theleve l
of comf ortwhen braking. *
NO
TEDama getothre adin gfrom dirton
wheel bolts #
Donotplace wheel boltsin san dor on
a dir tysur face. #
Unscr ew theupper mostwheel boltcom‐
ple tely. #
Screw align mentbolt 1intoth eth re ad
ins tead ofthewheel bolt. #
Unscr ew there maini ngwhee lbolts com‐
ple tely. 31
4
Wheels andtires

#
Remo vethewheel and,ifneces sary,stor eit
in thetrunk . #
Noteson remo ving anemer gency spare
wheel (/page31 7). Ins
talling ane wwh eel Re
quirement s:
R The wheel isremo ved(/ page31 4).
* NO
TEMer cedes-AMG vehicles #
Obser vetheno tesin theSupplement .
Yo uco uld other wise failto recogni ze
da ngers. &
WARNIN GRisk ofacci dent from losing a
whe el
Oil ed, grea sed ordamag edwhe elbol t/whe el
nut thre ads orwheel hub/wheel mounting
bolt thre ads can caus eth ewheel bolts/
wheel nutstocome loose.
As are sult, youco uld lose awheel whiledriv‐
ing . #
Neveroil orgrease theth re ads. #
Intheeve ntofdama getotheth re ads,
con tact aqu alif ied spec ialistwo rkshop
immediat ely. #
Have thedamag edwheel boltsordam‐
ag ed hub thre ads replaced. #
Donotcon tinue driving. #
Obser vetheinf ormation onthech oice of
tir es (/ page30 7).
Fo rtir es wit haspecif ieddirection ofrotatio n,an
ar ro w on theside wallof thetir eindicat esthe
cor rect dire ction ofrotatio n.Ob serveth edir ec‐
tion ofrotatio nwh en installing. #
Slide thewheel tobe mount edont oth e
align mentbolt andpush iton . #
Obse rveth eno teson installing anemer ‐
ge ncy sparewheel (/page31 7). &
WARNIN GRisk ofinju ryfrom tight ening
whee lbol tsand nuts
If yo utig hten thewheel boltsorwheel nuts
when theve hicle israised, thejac kcould tip. #
Onlytight enwheel boltsorwheel nuts
when theve hicle ison thegr ound. #
Obser vetheins truction sand safetyno teson
"Cha nging awheel" (/page30 7). #
Forsaf etyre ason s,on lyuse wheel bolts
whic hha ve been approvedby Mer cedes-
Benz andforth ewheel inqu estion .
* NO
TEDama getopaintw orkof thewheel
ri m when screwing onthefirs twh eelbo lt If
th ewheel hastoomuc hpla ywhen screw‐
ing inthefirs twh eelbo lt, thewheel rim pai nt
can bedama ged. #
Press thewheel firm lyag ains tth e
wheel hubwhen screwing onthefirs t
wheel bolt. Wheels
andtires 31
5

#
Tight enthewheel boltsevenlyin adi ag ona l
pa tter nin theor der indicat eduntil they are
fi ng er-tig ht. #
Unscr ew and remo vethealignment bolt. #
Tight enthelas twheel boltuntil itis fing er-
tig ht. #
Lowe rth eve hicle (/page31 6). Lo
we ring theve hicl eaf te ra wh eelch ang e Re
quirement s:
R The newwheel hasbeen installed
(/ page31 5). #
Tolowe rthe vehicl e:pla cethera tche tont o
th ehe xagon nutofthejac kso that thelet‐
te rs "AB "ar evis ible and turnco unt er-cloc k‐
wise. #
Tight enthewheel boltsevenlyin adi ag ona l
pa tter nin theor der indicat ed1 to5 with
an init ialmax imum forc eof 59 lb-ft(80 Nm). #
Tight enthewheel boltsevenlyin adi ag ona l
pa tter nin theor der indicat ed1 to5 to
th especif iedtight ening torq ue of96 lb-ft
(1 30 Nm) . &
WARNIN GRisk ofacci dent dueto inc or‐
re ct tigh tening torq ue
Th ewh eelscou ldcome looseifth ewheel
bolts orwheel nutsareno ttight ened tothe
pr escr ibed torq ue. #
Ensu rethat thewheel boltsorwheel
nuts aretight ened tothepr escr ibed
tight ening torq ue. #
Ifyo uar eno tsur e,do notmo vethe
ve hicle. Contactaqu alif ied spec ialist
wo rkshop andhave thetight ening tor‐
qu ech eckedimmediat ely. #
Chec kth etir epr essur eof thene wlyins talled
wheel andadjus tit ifnec essar y. #
Vehicl eswith tirepr ess urelos swa rning
sy stem: Restar tth etir epr essur eloss warn‐
ing system (/ page29 4).
Ex cep tion: thene wwheel isan emer gency
spa rewheel. #
Vehicl eswith atir epr ess uremonit oring
sy stem: Restar tth etir epr essur emonit oring
sy stem (/ page293).
Ex cep tion: thene wwheel isan emer gency
spa rewheel. 31
6
Wheels andtires

Emer
gency spar ewheel No
teson theemer gency spar ewheel &
WARNIN GRisk ofacci dent caused by
inc orrect whe eland tiredimensi ons
The wheelor tiresize andthetir etype ofthe
emer gency sparewheel orspar ewheel and
th ewheel tobe replaced maydif fer. The
emer gency sparewheel orspar ewheel can
sign ifican tly im pair drivin gch aract eristic sof
th eve hicle.
To preve nthazardous situa tions: #
Adaptyo ur drivin gst yle accor dinglyand
dr ive car efull y. #
Neverins tallmor eth an oneemer gency
spa rewheel orspar ewheel that dif fers
in size . #
Onlyuse anemer gency sparewheel or
spar ewheel ofadif fere nt size briefly. #
Donotsw itchof fESP ®
. #
Have theemer gency sparewheel or
spar ewheel ofadif fere nt size replaced
at thenear estqu alif ied spec ialistwo rk‐ shop.
Thenewwheel mustha ve the
cor rect dimensi ons. %
The eme rgency sparewheel issec ured inthe
emer gency sparewheel baginthetrunk .
Obser vethefo llo wing noteson remo ving an
emerg encysparewhee l:
R Beforestor ing theemer gency sparewheel,
mak esur eth er eis no air leftin thetir e.
If neces sary,allo wtheair toescape.
R Torelease airfrom thetir e: remo vethe
va lve cap ofthetir e.
R Press down theme talinse rtin theva lve
using apoint edobje ct,e.g. apen.
R Screw theva lve cap ontoth eva lve.
Obser vethefo llo wing noteson installing an
emer gency sparewheel:
R Chec kth etir epr essur eof theemer gency
spa rewheel installed. Correct thepr essur e
as neces sary. R
The maximum permissible speedwithan
emer gency sparewheel installed is50 mph
(80 km/ h).
R Donoteq uip theemer gency sparewheel
wit hsn ow chains .
R Replace theemer gency sparewheel afte rsix
ye arsat thelat est,re ga rdless ofwe ar.
% Ve
hicl eswith atir epr ess urelos swa rn‐
ing system: Ifan emer gency sparewheel is
ins talled thetir epr essur eloss warning sys‐
te m canno tfunction reliabl y.Onl yre star tth e
sy stem again when theemer gency spare
wheel hasbeen replaced withane wwheel.
Ve hicl eswith atir epr ess uremonit oring
sy stem: Ifan emer gency sparewheel is
ins talled thetir epr essur emonit oring system
cann otfunction reliabl y.Fo ra fe w min utes
af te ran emer gency sparewheel isins talled,
th esy stem mayst ill displa yth etir epr essur e
of there mo vedwheel. Onlyre star tth esy s‐
te m again when theemer gency sparewheel
has been replaced withane wwheel. Wheels
andtires 317

Be
sureto also obse rveth efo llo wing further
re lat ed subje cts:
R Noteson tirepr essur e(/ page288)
R Tire and Loadi ngInfo rm atio nplacar d
(/ page29 5)
R Tire pressur eta ble (/ page290)
R Noteson installing tires (/ page30 7) Inf
lating theemer gency spar ewheel *
NO
TEOverhea ting dueto thetir einf la‐
tion compressor running toolong #
Donotru nth etir einf lation compressor
fo rlong erthan tenminu teswit hout
int erru ption. Re
quirement s:
Com plywit hth emanuf acturer'ssafetyno teson
th est icke rof theemer gency sparewheel andon
th etir einf lation compressor . #
Remo vethest icke rwit hth elabel 50mph
(80 km/ h)from thetir einf lation compressor housing
andaffix it to theins trument cluster
wit hin thedr iver's field ofvision. #
Remo vethetir einf lation compressor from
th estor ag ewe llunder thetrunk floor
(/ page268). #
Pull filler hose 1and plug 3out ofthetir e
inf lation compressor housing. #
Inser tplug 7offiller hose 1inthesoc ket
on thetir einf lation compressor andthen
tur nit until plug7eng ages. #
Unscr ew thecap from theva lve on theemer‐
ge ncy sparewheel. #
Screw union nut2offiller hose 1onto
va lve. #
Mak esur eon and offswitc h4 ofthetir e
inf lation compressor issetto 0. #
Inser tplu g3 inasoc ketin your vehicle.
R 12Vsoc ket(/ page 105)
R Observeth eno teson soc kets (/ page 105). #
Pres sth est ar t/ stop butt ononce toswitc h
on thepo we rsupp ly(/ page12 5). #
Pres son andof fsw itch 4 onthetir einf la‐
tion compressor toI.
The tireinf lation compressor isswitc hedon.
The tireis inf lated. The tirepr essur eis
sho wnonmanome ter5. #
Pum pth etir eto thespecif iedtirepr essur e.
% The specif iedtirepr essur eis stat ed on the
label oftheemer gency sparewheel. #
When thespecif iedtirepr essur ehas been
re ac hed, press onand offswit ch4 onthe
tir einf latio ncom pres sor to0.
The tireinf lation compressor isswitc hedoff. 31
8
Wheels andtires

#
Press thest ar t/ stop butt ontoswitc hof fth e
po we rsupp ly. #
Ifth etir epr essur eis higher than thespeci‐
fi ed pressur e,press pressur ere lease valve
bu tton 6 unti lth ecor rect tirepr ess ureha s
bee nre ac hed. #
Unscr ew unio nnut 2offiller hose 1from
th eva lve. #
Screw theva lve cap oftheemer gency spare
wheel ontoth eva lve ag ain. #
Storefiller hose 1and plug 3inthelowe r
section ofthetir einf lation compressor hous‐
ing. #
Storeth etir einf lation compressor inthe
ve hicle. Wheels
andtires 31
9

Disp
laymes sages
Possible causes/conseq uencesand0050 0050
Solutions
0077 Check Tires *T
hetirepr essur ein one ormor etir es has dropped significantl y.The wheel position willbedispla yed. &
WARNIN GRisk ofan acci dent dueto insuf ficie nttirepr ess ure
R The tires can burst.
R The tires can wearexc essiv elyand/or unevenly.
R The driving charact eristic sas wellas thesteer ing and braking maybe greatl yim pair ed.
Yo uco uld then lose control of theve hicle. #
Obser vethere comme ndedtirepr ess ures. #
Adjus tth etir epr essur eif neces sary. #
Stop theve hicle inaccor dance withth etra ffic con dition s. #
Chec kth etir epr essur e(/ page288) andthetir es.
0077 Please Correct TirePres-
sure *T
hetirepr essur eis toolow in at leas tone ofthetir es, orthedif fere nce intirepr ess urebe twee nth eindividual
wheels istoogr eat. #
Chec kth etir epr essur eand add air,if neces sary. #
When thetir epr essur eis cor rect, restar tth etir epr essur emonit or(/ page293). Displa
ymessag esand warning/ indic ator lam ps 37
3