ignition MERCEDES-BENZ M-Class 2012 W166 Service Manual

Smar
tKeypositions
Smar tKey g
Toremove theSmartK ey
1 Power supply forsome consumers, such
as the windshield wipers
2 Ignition (powersupplyforallconsumers)
and drive position
3 Tostart theengine
As soon asthe ignition isswitched on,allthe
indicator lampsinthe instrumen tcluster light
up. Ifan indic atorlamp doesnotgoout after
the engineisstart ed orifit light sup while the
vehic leisin mot ion, see(Ypage 271).
If the SmartKey isin posit ion0in the ignit ion
lock foranext ende dperiod oftim e,itcan no
long erbe turned inthe ignit ionlock .The
steering isthen locked. Tounlock, remove the
SmartK eyand reinsert itinto theignition lock.
The steering islocked whenyouremove the
SmartK eyfrom theignition lock.
X Remove theSmartK eywhen theengine is
switched off.
The starter battery couldotherwise be
discharged.
If you cannot turntheSmartK eyinthe ignition
lock, thestarter battery maynotbecharged
sufficiently.
X Check thestarter battery andrecharge itif
necessary (Ypage 340).
or
X Jump-start thevehicle (Ypage 341). i
The
SmartK eycan beturned inthe
ignition lockeven ifit is not thecorrect
SmartK eyfor the vehicle. Theignition isnot
switched on.The engine cannot bestarted.
KEY LESS-GO General
informat ion
Vehicles withKEYLE SS-GO are equipp edwith
aS martKey featuringanintegrated KEYLESS-
GO function andadetacha bleStart/St op
button.
The Start/St opbutton mustbeinserted inthe
ignitio nlock andtheKEYLESS-GO keymust
be inthe vehicl e.
Pressi ngthe Start/St opbutton severaltimes
in successi oncorrespond sto the differe nt
SmartKey positions inthe ignitio nlock. This
is only thecase ifyou arenot depressing the
brake pedal.
If you depress thebrake pedalandpress the
Start /Stopbutton ,the engine starts
immediately.
The Start /Stopbutton canberemoved from
the ignition lock.Then, youcan insert the
Smart Keyinto theignition lock. i
You
donot have toremove theStart /Stop
button fromtheignition lockwhen you
leave thevehicle. However, youshould
alwa ystake theSmart Keywith youwhen
leaving thevehicle. Thevehicle canbe
start edwith theStart /Stopbutton andthe
electric alequipment canbeoperated while
the Smart Keyisin the vehicle. Driving
139Driving and parking Z

X
Insert Start/S topbutton :into ignition
lock ;. i
When
youinsert Start/S topbutton :
into ignition lock;,thesystem requiresa
detection timeofapp roximately two
seconds beforeyoucan useStart/S top
button :. Start/St
opbutton
= USA only
? Cana daonly
X Positio n0: ifStart/S topbutton :has not
yet been pressed ,this corresponds tothe
SmartKey beingremoved fromtheignition.
X Positio n1: press Start/S topbutton :
once.
You cannow activate thewindshi eld
wip ers, forexampl e. i
If
you press Start/S topbutton :twice
when inthis positio n,the powe rsupply is
deac tivat ed again .
X Pos ition 2(ign ition ):pre ssStart /S top
but ton: twice. i
If
you pressStart /S topbut ton: once
when inthis posi tion and thedriv er'sdoor
is open ,th epower supplyis deac tivat ed
again .
As soo nasthe ignition isswitched on,allthe
indicator lampsinthe instrument clusterlight
up. Ifan indicator lampdoesnotgoout after
the engine isstarted orifit lights upwhile the
vehicle isin motion, see(Ypage 271). Star
ting theengin e
Importa ntsafety notes G
WARNING Inhalation
ofexhaust gasishazardous toyour
health. Allexhaust gascont ains carbon
monoxide (CO),andinhaling itcan cause
unconsciousness andpossible death.
Do not run theengine inconfined areas(such
as agarage) whicharenot properly ventilated.
If you think thatexhaust gasfumes are
entering thevehicle whiledriving, havethe
cause determined andcorrect ed
immediately .Ify ou must driveunder these
condit ions,drive onlywith atleast one
window fullyopen atall times. i
Vehicles
withagasoline engine:the
catalytic converter preheats forupto30
seconds afteracold start.Durin gth is time,
th een gin esoun dmay bediff ere nt.
Aut oma tic trans mission X
Sh ift thetrans mis sion toposi tion P.
The trans mis sion position disp layinthe
mult ifunction disp laysho wsP
(Y page 145). i
You
canalso start theen gin ewhen the
tr ans mis sion isin posi tion N.
St artin gpr ocedu rewith theSm artKey X
To star tag asolineeng ine:turn the
SmartKey toposi tion 3in the ignition lock
(Y pag e139) andrelease itas soon asthe
engine isrunning.
X To start adiesel engine: turnthe
Smar tKey toposit ion2in the ignit ionlock
(Y page 139).
The % preglow indicatorlamp inthe
inst rumen tcluster lightsup.
X When the% preglo windic atorlamp
goes out,turnthe SmartK eytoposition 3
(Y page 139)andrelease itas soon asthe
engine isrunning. 140
DrivingDriving and parking

i
You
canstartthe engine without preglow
if the engine iswarm. i
You
canalso usethetouch-st artfunct ion.
To do this, turntheSmartK eytoposition 3
(Y page 139)andrelease itimmediately.
The engine thenstarts automatically .
Using KEYLESS-GO tostar tthe eng ine G
WARNING As
long asthe SmartKey isin you rvehicle, the
vehicle canbestart ed.Therefor e,never leave
children unattended inthe vehicle, asthey
could otherwiseacciden tallystart theengine.
When leaving thevehicle, alwaystake the
Smart Keywith youand lock thevehicle. Do
not leave children unattended inthe vehicle,
or with access toan unlock edvehicle. A
child's unsupervised accesstoavehicle could
result inan acciden tand/o rserious personal
injury. i
The
Start/ Stop button canbeused to
start thevehicle without insertingthe
Smart Keyintothe ignition lock.TheStart/
St op button mustbeinsert edinto the
ignition lockandtheSmart Keymust bein
the vehicle.
X Depress thebrake pedalandkeep it
depressed.
X To star tag asolineeng ine:press the
Start/Stop button(Ypag e139) once.
The engine starts.
X To start adiesel engine: presstheStart/
St op butt on(Ypage 139)onc e.
Preglow isact ivated andtheengin estar ts. Pulling
away
Autom atic transm ission G
WARN
ING It
is danger oustoshift theautomat ic
tr ansm ission outofparkin gposition Por
neutral position Nifthe engine speedis higher
thanidlespeed. Ifyour footisnot firmly
on the brake pedal, thevehicle could
accelerate quicklyforward orinreverse. You
could losecontrolofthe vehicle andhit
someone orsomethin g.Only shiftintogear
when theengine isidling normally andwhen
your right footisfirmly onthe brake pedal. i
It
is only possible toshift thetrans mission
from position Pto the desired position if
you depress thebrake pedal. Onlythenis
the parking lockreleased. Ifyou donot
depress thebrake pedal, youcan move the
DIRECT SELECT lever buttheparking lock
remains engaged.
X Depress thebrake pedalandkeep it
depressed.
X Shift thetrans mission toposition Dor R
(Y page 144).
X Relea sethe brake pedal.
X Carefully depresstheaccelerator pedal.
The electric parking brake(Ypage 156)is
automatically released.
The redF (USAonly)or! (Canada
only) indicator lampinthe instr ument
cluster goesout. i
The
vehicle lockscentrally once youhave
pulled away.The locking knobsinthe doors
drop down.
You canopen thedoors fromtheinside at
any time.
You canalso deactivate theautomatic
locking feature(Ypage 235). i
Upshifts
takeplace athigher engine
speeds afteracold start. Thishelps the
catalytic convertertoreach itsoperating
temperature morequickly.
Pulling awaywithatra iler To
ensure thatyoudonot rollbackwards
when pullingaway onanuphill slope, engage
the electric parking brake. Driving
141Driving and parking Z

X
When thevehicle isstat ionary, depress the
brake pedal.
X Push theDIRE CTSELECT leveruppast the
first point ofresistan ce.
Shift ingtoneutr alN X
When thevehicle isstat ionary, depress the
brake pedal.
X Push theDIRE CTSELECT leverupordown
to the first point ofresistan ce.
If the engine hasbeen switched off,the
automatic transmission automatic ally
switches toN.
Rema ininginneutr alN
If the automatic transmission isto remain in
neutr alN, e.g. forwashing thevehicle incar
washes withatowing device, pleaseobserve
the following instruct ions: G
WARN
ING When
leaving theSmart Keyinthe start er
switch, donot leave children unattended in
the vehicle. Itis possible forchildren toswitch
on the ignition whichcouldresult in
unsupervised useofvehicle equipment.
Unsuperv iseduseofvehicle equipment could
result inan accident and/orserious personal
injury.
Using theSma rtKey:
R make surethattheignition isswitched on.
R when thevehicle isstat ionary, depress the
brake pedalandkeep itdepressed.
R shift toneutr alN.
R release thebrake pedal.
R ifapplied, releasetheelectr icparking
brake.
R switch offthe ignition andleave the
Smart Keyinthe ignition lock.
Using KEYLESS-GO:
R make surethattheignition isswitched on.
R when thevehicle isstat ionary, depress the
brake pedalandkeep itdepressed.
R engage parkposition P. R
release thebrake pedal.
R remove theStart/ Stop button fromthe
ignition lock.
R insert theSmart Keyinto theignition lock.
R switch onthe ignition .
R depress thebrake pedalandkeep it
depressed.
R shift toneutr alN.
R release thebrake pedal.
R ifapplied, releasetheelectr icparking
brake.
R switch offthe ignition andleave the
Smart Keyinthe ignition lock.
Shift ingtotransmission positionD X
When thevehicle isstat ionary, depress the
brake pedal.
X Push theDIRE CTSELECT leverdown past
the first point ofresistan ce. Tr
ansmission positiondisplay
The curren ttransmis sionposition isshow nin
the multifu nctio ndisplay. :
Tran smiss ionposit ion
The arrows inthe transm ission position
display showhowandintowhich
tr ansm ission positionsyoucan chan geusing
the DIRECT SELECT lever .
! Ifthe transm ission positiondisplay inthe
mult ifunc tiondisplay isnot work ing,you
should pullaway carefully tochec kwhether
the desired transmission positionis
engaged. Selecttransmission positionD.
Do not restrict theshift range. Automat
ictransmission
145Driving and parking Z

Problems
withthetransmission Problem Possible
causes/co nsequences andM Solutions
The
transm issionhas
problems shiftinggear. The
transm issionislosing oil.
X Have thetransm issioncheckedataqual ified specialist
workshop, e.g.anauthorized Mercedes-B enzCenter,
immediately. The
acceleration ability
is deteriorating.
The transm issionno
longer changes gear. The
transm issionisin emergency mode.
It is only possible toshift intosecon dgear andreverse gear.
X Stop thevehicle.
X Shift thetransm issiontoposition P.
X Switch offthe engine.
X Wait atleast 10seconds beforerestartingthe engine.
X Shift thetransm issiontoposition Dor R.
If D is selected, thetransm issionshiftsintosecon dgear; ifR is
selected, thetransm issionshiftsintoreverse gear.
X Have thetransm issioncheckedataqual ified specialist
workshop, e.g.anauthorized Mercedes-B enzCenter,
immediately. Refueling
Import
antsafety notes G
WARNING Gasoli
neand diesel fuelsarehighly flammable
and poisonous. Theyburnviolently andcan
cause serious injury.
Never allowsparks, flamesorsmoking
materials neargasoline ordiesel fuel!
Turn offthe engine beforerefueling.
Whenever youarearound gasoline ordiesel
fuel, avoid inhaling fumesandanyskin or
clothing contact.Extinguish allsmoking
materials.
Direct skincontactwith fuels andthe
inhalation offuel vapors aredamaging your
health. G
WARNING Overfilling
ofthe fuel tank maycreate
pressure inthe system whichcouldcause a
gas discharge. Thiscould cause thegasoline to
spray backoutwhen removing thefuel
pump nozzle,which couldcause personal
injury. G
WARNING Do
not filldiesel tankswith gasoline. Donot
mix diesel fuelwith gasoline. Otherwise the
fuel system andengine couldbedamaged. In
addition, thevehicle couldcatch fire.
! Donot use gasoline torefuel vehicles with
a diesel engine. Donot use diesel torefuel
vehicles withagasoline engine.Evena
small quantity ofthe wrong fuelwill
damage thefuel system andengine.
! Donot switch onthe ignition ifyou
accidentally refuelwiththewrong fuel.
Otherwise, thefuel willenter thefuel lines.
Notify aqual ified specialist workshop and
have thefuel tank andfuel lines drained
completely. Refueling
149Driving and parking Z

:
Toopen thefuel filler flap
; Toinsert thefuel filler cap
= Fuel type
? Tire pressure table
Opening X
Switc hoff the engine.
X Remove theSmart Keyfrom theignition
lock.
KEYLE SS-GO: open thedriver’s door.This
switches theignition toposition 0,which
correspon dstohaving removed the
Smart Key.Thedriver’s doorcanbeclosed
again.
X Press thefuel filler flapinthe direction of
arrow :.
The fuel filler flapswings up.
X Turn thefuel filler capcount er-clockwise
and remove it.
X Insert thefuel filler capinto theholder
bracket onthe inside offiller flap;.
X Completely insertthepump nozzleinto the
filler neck andrefuel.
X Only fillthe tank untilthepump nozzle
switches off.
! Overfilling thefuel tank could damage the
fuel system. Closing X
Replace thefuel filler capand turn it
clock wise. Thefuel filler capaudibl y
engages.
X Close thefuel filler flap. i
If
you drive withthefuel filler capopen,
reserve fuelwarning lamp8 flashes. In
addition, the; Check Engine warning
lamp maylight up.Am essage appears in
the multifunc tiondisplay (Ypage 257).
For furth erinfor mation onwarning and
indicat orlamps inthe instrument cluster,
see (Ypage 276). Refueling
151Driving and parking Z

Problems
withfuelandthefuel tank Problem Possible
causes/co nsequences andM Solutions
Fuel
isleaking fromthe
vehicle. G
Risk
ofexplosion orfire The
fuel lineorthe fuel tank isdefective.
X Turn theSmartK eytoposition 0(Ypage 139)inthe ignition lock
immediately andremove it.
X Do not restart theengine underanycircumst ances.
X Consult aqual ified specialist workshop. The
fuel filler flap
cannot beopened. The
fuel filler flapisnot unlocked.
or
The SmartK eybattery isdischarged.
X Unlock thevehicle (Ypage 72).
or
X Unlock thevehicle usingthemechanical key(Ypage 75). The
fuel filler flapisunlocked, buttheopening mechanism is
jammed.
X Consult aqual ified specialist workshop. The
engine willnot
start. The
fuel tank ofavehicle withadiesel engine hasbeen run
completely dry.
X Refuel thevehicle withatleast 5.3USqt(5liters) ofdiesel.
X Turn theignition onfor atleast 10seconds (Ypage 139).
X Start theengine continuously forupto10 seconds untilitruns
smoothly.
If the engine doesnotstart:
X Turn theignition onagain forapproximately 10seconds
(Y page 139).
X Start theengine againcontinuously forupto10 seconds until
it runs smoothly.
If the engine doesnotstart after three attempt s:
X Consult aqual ified specialist workshop. DEF
Import antnotes onuse To
funct ionproperly, BlueTECexhaustgas
aftert reatment mustbeoperated withthe
reducing agentDEF. When
theDEFs upply hasalmo strun out,th e Che
ckAdditiveSee Operator's Man
ual mes
sage issho wninthe
mult ifunction disp lay.
When theDE Fs upply sinks toamin imum
leve l,th e Rem
aining Starts:16 mes
sage
is sho wninthemult ifunction disp lay. 152
Ref
uelin gDriving and parking

Opening
theDEF filler cap The
filler neckfor DE Fisbehind thefuel filler
flap.
The fuel filler flapisunlocked orlocked
automaticall ywhen youopen orclose the
vehicle withtheSmartKey orwith KEYLES S-
GO. X
Switch offthe ignition.
X Press thefuel filler flapinthe direction of
arrow :.
The fuel filler flapswings up.
X Turn blueDEFfiller cap;
counterc lockwise andremove it.
DEF filler cap;issecured withaplastic
strap.
DEF refill bottle DEF
refill bottles canbeobtained atmany gas
stations oratan authorized Mercedes-Benz
Center. Refillbottles without athreaded cap
do not provide overfillprotection.DEF may
leak ifoverfilled. Mercedes Benzprovides
special refillbottles withthreaded caps.
These areavail able atany authorized
Mercedes-Benz Center. X
Unscrew theprotect ivecap from DEFrefill
bottle :.
X Place DEFrefill bottle :onthe filler neck
as shown andscrew iton clockwise untilit
is hand-tight.
! Only screw onthe DEF refill bottle hand-
tight. Itcould otherwise bedamaged .
X Press DEFrefill bottle :inthe direction of
the filler neck.
The DEF tank isfilled. Thismay take upto
one minute. i
When
DEFrefill bottle :isno longer
pressed, fillingstops andthebottle maybe
taken offagai nafter being only partially
emptie d.
X Rel eas eDEF refillbottle :.
X Turn DEFrefillbottle :counterclo ckwise
and remove it.
X Screw onthe cover ofDEF refillbottle :
aga in. 154
Refuel
ingDriving and parking

Closing
theDEF filler capand fuel filler
fla p X
Plac eDE Ffiller cap;onthe filler neckand
tur nit clo ckwi se.
X To closethe fuel fillerf lap, press itin the
direc tionofarrow :.
X Dr ive ataspeed above10mph (16km/h) .
The Chec
kAddi tive SeeOperator's Manu
al mess
agedisappears after
approx imatelyone minute. i
If
the Chec
kAddi tive See Oper
ator'sManu al mess
agecontinues
to be shown inthe mult ifunc tiondisplay,
you need toadd moreDE F. Par
king Imp
ortant safety notes G
WARN
ING Do
not park thisvehic lein areas where
com bustib lemat erials cancom eint ocon tact
with thehot exhaust system. Donot park the
vehic leon dry grass landorharve stedgrain
fields. Combust iblematerials, suchasgrass ,
hay orleaves couldbeignit edbythe hot
exh aust systemand cause avehic lefire . Unin
tended vehic lemov emen tcan cause
serio usperso nalinjury ordamage tothe
vehic leor the vehic ledrive train. Toreduc e
such risks,always dothe followin gbefor e
tur nin goff the engineand leavin gthe vehic le:
R keep yourright footonthe brak epedal.
R apply theelect ricpark ingbrak e.
R shift theautom atictransm ission intopark
posit ionP.
R slowly release thebrak epedal.
R when parkedon anincline, always turnthe
front wheels towards theroad curb.
R turn theSmartKey inthe ignition lockto
position 0and remove theSmartKey from
the ignition lock,orpress theKEYLES S-GO
Start /Stopbutton.
R take theSmartKey withyouand lock the
vehicle whenleaving. Switching
offthe engine
Import antsafety notes G
WARNING Never
switch offthe engine whilethevehicle
is in motion.
There isno brake boostforthe service brake
if the engine isnot running. Ifthe ignition is
switched off,there isalso nopower
assistance forthe steering.
You willrequire considerably moreeffort to
steer andbrake andyoucould therefore lose
cont rolofthe vehicle andcause anaccident. G
WARNING Keep
inmind thatturning offthe engine alone
only willshift theautomatic transmission into
neutral position Nautomatically .
Always shifttheautomatic transmission into
park position Pbefore turning offthe engine.
Otherwise thevehicle couldrollaway which
could result inan accident and/orserious
personal injury. Park
ing
155Driving and parking Z

X
App lythe electri cpark ing brak e.
X Sh ift thetrans mis sion toposi tionP.
Using theSm artKey X
Turn theSm artKey toposi tion0 inthe
ign ition lockand remove it.
The imm obiliz erisact ivat ed. i
If
you turnoff theen gin ewit hth e
Sm artKey and then rem ove itfrom the
ign ition lockor open afron tdoor ,th e
auto matictrans mis sion shiftsto P
auto maticall y.
Using KEYLESS- GO X
Pre sstheSt art /S topbut ton( Ypage 139).
The engin estops andallthe indicat or
lamps inthe instrument clustergoout. i
If
you usetheStart/ Stop butt ontoswitc h
off the engin e,the automatic transmission
shift sto Nautomatic ally.Ifyou then open
one ofthe fron tdoors, theautomatic
trans mission shiftstoP. i
In
an emergenc y,the engine canbe
turned offwhile thevehicle isin motion by
pressing andholding theStart /Stopbutton
for three seconds. Elec
tric par king brake
General information i
The
electric parking brakeperforms a
funct iontest atregular intervalswhile the
engine isswitched off.The sounds thatcan
be heard whilethisisoccurrin gare normal. G
WARNIN
G When
leaving thevehicle, alwaysremove the
Smart Keyfrom thestart erswitch, takeitwith
you, andlock thevehicle. Donot leave
children unattendedinthe vehicle, orwith
access toan unlocked vehicle.Children could
release theparking brakeand/or shiftthe
automatic transmission outofpark position P,
either ofwhich couldresult inan accident
and/or serious personal injury. Applying/releasing
manually X
To app ly:press handle :.
The redF (USAonly)or! (Canada
only) indicator lampinthe instr ument
cluster lightsup. i
The
electric parking brakecanalso be
applied whentheSmart Keyisremoved.
X To release: pullhandle :.
The redF (USAonly)or! (Canada
only) indicator lampinthe instr ument
cluster goesout. i
The
electric parking brakecannotbe
released unlesstheSmart Keyisin position
1 in the ignition lockorthe ignition has
been switched onusing theStart /Stop
button .
To ensure thatyoudon't rollbackwards when
pulling awayonanuphill slope, engage the
electric parking brake(Ypage 141).
Applying automat ically Your
vehicle's electricparking brakeis
automatically appliedifDIS TRONIC PLUSor
the HOLD functionbring thevehicle toa
standst ill,orare engaged tokeep thevehicle
station ary.Inaddition, atleast oneofthe
following conditionsmust befulfilled: 156
Par
kingDriving and parking