ECU MERCEDES-BENZ SLC 2020 Repair Manual

X
Make surethattheignition isswitched off
(Y page 118).
or
X When usingtheSmartK ey,turn theSmart-
Key toposition 0092inthe ignition lockand
remove it(Y page 118).
X Secure thevehicle against rollingaway
(Y page 134).
All indicator lampsinthe instrumen tcluster
must beoff.
The fuses arelocated invarious fuseboxes:
R Fuse boxinthe engine compartmen tonthe
left-hand sideofthe vehicle, whenviewed in
the direction oftravel
R Fuse boxinthe trunk Fuse
boxinthe engine compart ment
i Observe
the"Important safetynotes" sec-
tion (Ypage 266). G
WARNING
When thehood isopen andthewindshield
wipers aresetinmotion, youcan beinjured
by the wiper linkage. Thereisar isk ofinjury.
Always switchoffthe windshield wipersand
the ignition beforeopening thehood. X
Make surethatthewindshield wipersare
turned off.
X Open thehood.
X Use adrycloth toremove anymoisture
from thefuse box.
X To open: openclamps 0044.
X Remove fuseboxcover 0043forwards. X
To close :check whether theseal islying
correct lyin cover 0043.
X Insert cover0043atthe rear ofthe fuse box
into theretainer.
X Fold down cover 0043and close clamps 0044.
X Close thehood. Fuse
boxinthe trunk
i Observe
the"Important safetynotes" sec-
tion (Ypage 266). The
fuse boxislocated inthe trunk behind the
partition covering.
X Open thetrunk lid.
X To open: release cover0043onthe right and
left-hand sideswithaflat object .
X Open cover 0043downwards inthe direction
of the arrow. Fuses
267Breakdown assistance Z

Avoi
dtire pre ssu res thatare too high inall
the tires,incl uding the sparewh eel.
Ove rinflated tiresm ay:
R incr ease the braking dista nce
R ad ver selya ffect handl ing
R we arexce ssivel ya nd/or unevenl y
R ha ve an adver seeffe cton ridec omf ort
R be more susce ptiblet od amage
Maxi mum tirepres sure s 0043
Exam ple: ma ximu mpermi ssi blet ire pre s-
su re
Nev erexce edthe maximu mpermi ssi blet ire
infl ation pre ssu re.Alw ayso bserve the reco m-
mend edtire pressu refor your veh iclew hen
ad jus ting thetire pressu re(Y page 271) .
i The
actu alvalues for tiresareveh icle-sp e-
cifi cand maydeviate from thevalues inthe
il lu stra tion. Che
ckingt he tire pres sure s
Impo rtant safetynotes The
tirepressu remoni tordoes not warnyou
of:
R inco rrectly settire pressu re
R sudd en loss oftire pressu re,e.g.from afor-
ei gn object thathas penetra tedthetire
Obs ervethe notes ontire pressu re
(Y page 271 ). Info
rma tiono nairpre ssu refor the tireson
yo ur veh iclec an be fou nd:
R on the vehicle's Tire and Loading Info rma -
tio np laca rd on the B-pi llar
R on the tire pressu retab lein the fuel filler
fla p
R in the "Tire pre ssu re" section
Che ckingt ire pres sure smanua lly To
determ ineand setthe corr ecttire pressu re,
pro cee dasfollows :
X Re move thevalve cap ofthe tire thatist o
be che cked .
X Pre ssthe tire pressu regaug es ecurelyo nto
the valve .
X Re ad the tire pressu reand comp arei ttot he
reco mme ndedvalue on the Tire and Loading
Info rma tionp laca rd orthe tire pressu re
tab le(Y page 271 ).
X Ifthe tire pressu reistoo low, incr ease the
tire pressu reto the reco mme ndedvalue.
X Ifthe tire pressu reistoo high, release air.
To do so, pressdown the meta lpininthe
va lve ,using the tipofap en for exa mpl e.
The ncheck the tire pressu reagainu sing the
tire pressu reche cker.
X Screw thevalve cap onto thevalve .
X Re peat thes estep sfor the othe rtire s. Tire
pres sure loss wa rning sys tem
(C anada only)
Ge neral notes Whi
lethe vehiclei sinm otion, the tire pres-
su re loss wa rning system monitorsthesettire
pre ssu reusing the rota tional speedofthe
wh eels.T hise nables the system todetect sig-
nifi cant pressu reloss inat ire.Ift he spe edof
rota tiono fa wheelcha nge sasa resulto fa
lo ss ofpre ssu re,acorresp ond ingwarning
mes sage willap pe ar inthe multifu nctio ndis-
pl ay .
Yo uc an reco gnizethe tire pressu reloss wa rn-
ing bythe Run FlatIndica tor Active Run
FlatIndica tor Active
Pre ss 'OK'toR estar t Pre
ss 'OK'toR estar tmes sage which
ap pe arsi nt he Ser v. Ser
v.menu ofthe multifu nc-
tio nd ispl ay .Info rma tiono nthe mes sage dis-
pl ay can befou ndinthe "Resta rting thetire 27
4 Tire
pres sureWhe elsa nd tire s

is
shown inthe Serv . Serv
.men uofthe multif unc-
tion display. Ex
ample: currenttirep ress uredisplay
For informat iononthe mess agedisplay, refer
to the "Check ingthe tirep ress ureelect roni-
cally" section(Ypage 277).
Imp ortant safet ynotes G
WARN
ING
Eac htire, inc luding thespare (ifprov ided),
should bechec kedatleast onceam onth
when coldandinflated tothe press urerec-
omme ndedbythe vehic lemanuf acturer on
the Tire andLoadin gInformat ionplacard on
the drive r'sdoor B-pillar orthe tirep ress ure
label onthe inside ofthe fuel filler flap.If
your vehic lehas tires ofad iffe ren tsize than
the size indic ated onthe Tire andLoadin g
Inf ormat ionplacard orthe tirep ress ure
label, youshould determin ethe proper tire
press ureforthosetires.
As anadded safetyfeat ure, your vehic lehas
been equipped withatirep ress uremon itor-
ing syst em(TPMS )that illuminat esalow tire
press uretelltalewhen oneormore ofyour
tir es are sign ifican tlyunder inflated. Accor d-
ingly, when thelow tirep ress uretelltaleillu-
min ates, youshould stopand chec kyour
tir es assoon aspossible ,and inflate themt o
the proper pressure.Drivin gonas ignifi-
can tlyunder inflated tirec auses thetiret o
over heat andcanlead totiref ailure. Under-
inf lation alsoreduc esfuel effic iencyand tire
tr ead life,and may affec tthe vehic le'shan-
dling andstopping ability.
Please notethat the TPMS isnot asubst i-
tut efor proper tirem aint enan ce,and itis
the drive r'srespo nsibilit ytom aintaincor-
rec ttirep ress ure, even ifunder inflation has not
reach edthe level totrigger illuminat ion
of the TPMS lowtirep ress uretelltale.
Your vehic lehas also been equipped witha
TPMS malfun ction indic atortoindic ateifthe
syst emisnot operat ingproper ly.The TPMS
malfun ction indic atoriscom bined withthe
low tirep ress uretelltale. When thesyst em
dete ctsam alfunction, thewarnin glamp will
flash forapprox imatelyam inute and then
remain continuously illuminat ed.This
sequen cewill berepeat edever ytimet he
vehic leisstar ted aslong asthe malfun ction
exis ts.
When themalfun ction indic atorisillumina-
ted, thesyst emmay notbeable todete ctor
sign allow tirep ress ureasintended .TPMS
malfun ctions may occurfor avariet yofrea-
son s,inc luding theinstallation ofinc ompat i-
ble replac ementoralter natetires orwheels
on the vehic lethat preventtheTPMS from
func tioningproper ly.Always checkthe
TPMS malfun ction tellt aleafterreplac ing
one ormore tires orwheels onyour vehic le
to ens ure that thereplac ementoralter nate
tir es and wheels allowtheTPMS tocon tinue
to func tion proper ly.
It is the drive r'srespo nsibilitytoset the tire
press uretothat recomme ndedforcold tires
which issuitable forthe operat ingsituat ion
(Y page 271).Notet hat the correcttirep res-
sure forthe curr entoperat ingsituat ionmust
firs tbetaught -intothe tirep ress uremon itor.
If as ubst antialloss ofpress ureoccurs, the
warnin gthreshold forthe warnin gmessage is
aligned tothe taught -inrefe rencevalues.
Restar tthe tirep ress uremon itorafteradjust -
ing the press ureofthe cold tires
(Y page 278). Thecurrentpress uresare
saved asnew referencevalues. Asaresult ,a
warnin gmessage willappear ifthe tirep res-
sure drops significant ly.
The tirep ress uremon itordoes notwarn youof
an incorre ctly set tirep ress ure. Obser vethe
not eson the recomme ndedtirep ress ure
(Y page 271).
The tirep ress uremon itorisnot able towarn
you ofas udden lossofpress ure,e.g.ifthe
tir ei sp enet ratedbyaf oreign object.Int he
even tofas udden lossofpress ure,bringthe 276
Tir
ep ressur eWheels andtires

If
the wheel positio nson the vehicle arerota-
ted, thetire pressu resmay bedispl ayedfor
the wrong positionsfor ashort time. Thisis
rectified afterafew minutes ofdriving, andthe
tire pressu resare displ ayedfor the correct
positio ns.
Restarting thetire pressure monitor When
yourestart thetire pressu remonitor, all
existing warning messagesare dele tedand the
warning lampsgoo ut. The monitor usesthe
currently settire pressu resasthe reference
valu esfor monitoring. Inmost cases, thetire
pressu remonitor willautoma tically detect the
new reference valuesafter youhave changed
the tire pressu re.However, youcan also set
reference valuesmanua llyas describe dhere.
The tirepressu remonitor thenmonitors the
new tirepressu revalu es.
X Set thetire pressu reto the valu erecom-
mended forthe corresponding drivingsitua-
tion onthe Tire andLoadi ngInformation
pla card onthe driver's sideB-pilla r
(Y page 271).
Additional tirepressu revalu esfor different
load scan also befound onthe tire pressu re
table onthe inside ofthe fuel fillerflap
(Y page 271).
X Make surethatthetire pressu reiscorrect
on allfour wheel s.
X Ensure thattheSmartKey isin positio n0048
in the ignition lock.
X Press the0059 or0065 button onthe steer-
ing wheel toselect theServ. Serv.
menu.
X Press the0063 or0064 button toselect
Tire Pressure Tire
Pressure.
X Press 0076.
The multifu nctiondisplayshows thecurrent
tire pressu refor the individ ualtires orthe
Tire pressure willbedisplayed Tire
pressure willbedisplayed
after driving afew minutes after
driving afew minutes message.
X Press the0064 button.
The Use Current Pressures asNew Use
Current Pressures asNew
Reference Values Reference
Valuesmessage appearsinthe
multifu nctiondisplay.
If you wishtoc onfirm therestart:
X Press 0076.
The Tire Press. Monitor Restarted Tire
Press. Monitor Restarted
message appearsinthe multifu nctiondis-
pla y. After
driving forafew minutes, thesystem
checks whether thecurrent tirepressu res
are within thespecifie drange. Thenew tire
pressu resare then accepted asreference
valu esand monitored.
If you wishtoc anc elthe restart:
X Press 0038.
The tirepressu revalu esstored atthe last
restart willcontinue tobe monitored. 278
Tire
pressureWheel sand tires

Clean
thec ontac tsurf aces ofthew heel and
th eb rak edisc thoro ughly everytim eaw heel
is rot ate d.Chec kthe tirep ressur eand,ifn ec-
ess ary, restartthe tirep ressur eloss warn ing
syst emorthet irep ressur emonito r. Direct
ionofrot ation
Tire swithas pecifiedd irection ofrot atio nhave
addit ionalben efits,e.g .ift he re isar isko f
hydr oplan ing.Thes eadvan tagescan onlybe
gain edifth et ires are install ed correspo nding
to thed irection ofrot atio n.
An arrow onthes idew allofthet irei nd icat es
its correct dire ction ofrot atio n. St
ori ng wheels
St ore wheel sthata re notb ein gu sed inac ool,
dry and preferably dark place.Pro tect thet ires
fr om oil,grease, gaso linea nd diese l. Mou
nting awheel
Pr epa ringthe vehi cle X
Stop thev ehicle onsolid ,non -slipp ery and
leve lground.
X Ap ply thee lectric park ingbrak emanually.
X Bring thef ront wheel sintot he straigh t-
ahead position.
X Sh ift thet rans mis sion toposi tion005D.
X Swit choff thee ngine.
X Veh icles withoutKEYLESS- GO:remove
th eS martKey from thei gn ition lock.
X Veh icles withKEYLESS- GO:open thed riv-
er' sd oor .
The vehicle elec tron ics nowh ave status 0.
This isthes ame astheS martKey having
been removed.
X Veh icles withKEYLESS- GO:remove the
St art /S topb utto nf romt heignition lock
(Y page 118).
X Ifinc luded inthev ehicle equipm ent,rem ove
th et ire- ch ang etoolkitfrom thev ehicle .
X Saf eguar dthe veh icle again stroll ing away.
i Due
todiff ere nces inveh icle equipm ent,
no ta llveh iclesareequipp edwithat ire-
ch ang etoolkit.F or inform ationonw hich to
ols are required toper formaw heel
ch ang eonyour vehicle,con sul tana uth or-
ize dM erced es-Ben zCenter.
Nec essary tire-ch ang ingtools can include,
for example :
R Jack
R Whee lcho ck
R Lug wren ch
Secur ingthev ehi cle toprevent itfrom
rol ling away If
your vehicle isequipp edwithaw heelchoc k,
it can befoun dint he tire-ch ang etoolkit
(Y page 253).
The foldingwheel choc kisa na ddit ionalsafe ty
meas uretopre ven tthe veh icle from rolling
away, forexample whenchang ingawheel .
X Fol db othp lates upward s0043.
X Fol do utlower plate0044.
X Guide thel ugs onthel ower platefully into
th eo pen ingsinb ase plate0087. X
Plac echockso rother suit able items unde r
th ef ront and rear ofthew heel that isdiago-
nall yoppo sitet he wheel youwish to
ch ang e. 290
Cha
nging awheelWh eels andtires

Rais
ingt he vehic le G
WARNI
NG
If yo ud on otpos ition the jack corre ctlyat
the appro priate jacki ngpointofthe vehicle,
the jack couldtip ove rwitht he veh icle
rai sed .The re isar isko finju ry.
Only position the jack atthe appro priate
jacki ngpointofthe vehicle. The base ofthe
jack mustbep ositioned vertically,d irectl y
und erthe jacki ngpointofthe vehicle.
! Only
position the jack atthe appro priate
jacki ngpointofthe vehicle. Othe rwise, you
cou ldda mag ethe veh icle.
Obs erve thefollowi ng when raising thevehi-
cle :
R To raise the vehicle, only uset he veh icle-
spe cificjack that hasb eent este dand
ap pro ved byMer cedes-Be nz.Ifus ed inco r-
rectl y,the jack couldtip ove rwitht he veh i-
cle raised .
R The jack isdes igned only toraise and hold
the vehiclef or as horttime whileaw heel
is bei ng cha nged .Itm ustn ot be used for
per formi ngmai ntenance workund erthe
veh icle.
R Avoi dchanging thewheel onuphilla nd
dow nhillslopes .
R Befo reraising thevehicle, secu reitfrom
rol ling away by applying the parking brake
and inserting wheel chocks .Don otdisen-
ga ge the parking brakewhilet he veh iclei s
rai sed .
R The jack mustbep lace do naf irm,flata nd
non-sl ipsurfa ce. Onaloo se surfa ce, alarge ,
fla t,load -bea ring underlay mus tbeu sed. On
as lipp ery surfa ce, anon-sl ipund erlay mus t
be used, e.g. rubber mats .
R Do not usew oodenb locks orsim ilar obje cts
as ajack underlay.O the rwise, the jack will
not beableto ach ieve its load -bea ring capa-
city duet ot he res tricte dheight.
R Ma kesure that thedistance betweenthe
und ersideo fthe tire sand the ground does
not excee d1.2in(3 cm).
R Neve rplace your hands and feetunder the
rai sed vehicle.
R Do not lieu nder the vehicle.
R Do not startthe engi newhen the vehiclei s
rai sed . R
Do not openorclose ad ooro rthe trunk lid
wh en the vehiclei sr aised .
R Ma kesure that noper sons arepresent in
the vehiclew hent he veh iclei sr aised . X
Usi nglugw rench 0043,l oosent he boltson
the wheel youw isht oc hange byabou to ne
ful lturn. Donot unscrew theboltscom-
pl etel y. The
jacki ngpoints are locate djust behindthe
front wheel hou sing sand just infront ofthe
rea rwheelhou sing s(arrow s).
Vehi cles with AMG equipmen t:the vehicle
ha sc ove rsinsta lled topro tect thevehicle
bod ynext tothe jacki ngpoints onthe outer
sil ls. Cha
ngingaw heel
291Whe elsa nd tires Z

!
To
prevent damage tothe paintwork, hold
the wheel securely againstthe wheel hub
while screwing inthe first wheel bolt. X
Clea nthe wheel andwheel hubcont actsur-
faces.
X Slide thewheel tobe mounted ontothe
alignment boltandpush iton.
X Tighten thewheel boltsuntiltheyarefinger-
tight.
X Unscrew thealignment bolt.
X Tighten thelast wheel boltuntil itis finger-
tight.
X Vehicles
withacollapsible sparewheel:
inflate thecollapsi blespare wheel
(Y page 296).
Only thenlower thevehicle.
Low ering thevehicl e G
WARNING
The wheels couldcome looseifthe wheel
bolts orwheel nutsarenot tightened tothe
prescribed tighteningtorque.Thereisar isk
of an accident.
Ensure thatthewheel boltsorwheel nuts
are tightened tothe prescribed tightening
torque.
If you arenot sure, donot move thevehicle.
Contact aqualified speciali stworkshop and
have thetightening torquechecked immedi-
ately.
! Vehicles
withacollapsible spare
wheel :before lowering thevehicle, inflate
the collapsi blespare wheel withthetire
inflation compressor. Thewheel rimcould
otherwise bedamage d. X
Turn thecrank ofthe jack counter-c lockwise
until thevehicle isonce againstanding
firmly onthe ground.
X Place thejack toone side. X
Tighten thewheel boltsevenly inac ross-
wise pattern inthe sequence indicated(0043
to 0083). Thespecified tightening torqueis
96 lb-ft (130 Nm).
X Turn thejack back toits initial position.
X Stow thejack andtherest ofthe vehicle
tools inthe trunk again.
X Vehicles withAMG equipment: insertthe
cover intotheouter sill.
X Check thetire pressure ofthe newly moun-
ted wheel andadjust itifnecessary.
Observe therecommended tirepressure
(Y page 271).
When youaredriving withthecollapsi ble
spare wheel mounted, thetire pressure loss
warning systemorthe tire pressure monitor
cannot function reliably.Only restart thetire
pressure losswarning systemortire pressure
monitor whenthedefective wheelhasbeen
replaced withanew wheel.
Vehicles withatire pressure controlsys-
tem: allinstalled wheelsmustbeequip ped
with functionin gsensors. Wheel
andtirecombination s
You canaskforinformation regardingpermit-
ted wheel/tire combinations atan authorized
Mercedes-Benz Center.
! For
safety reasons, Mercedes-Benz recom-
mends thatyouonly usetires andwheels
which havebeen approved byMercedes-
Benz specificall yfor your vehicle. Wheel
andtirecombin ations
293Wheels andtires Z