ignition MERCEDES-BENZ M-Class 2012 W166 Owner's Guide

X
To switcho ff:set the rocker switch tothe
| position.
The interior lighting automatical lyswitches
on ifyou :
R unlock thevehicl e
R open adoor
R remove theSmartKey fromtheignitio nlock
The interior lightisactivated forashort while
when theSmart Keyisremoved fromthe
ignition lock.Youcanactivate thisdelay ed
switch- offusing theon-board computer
(Y page 235).
Manua linterior lighting control X
To switch thefront interior lighting on:
set the rock erswitch tothe c position.
X To switch thefront interior lighting off:
set the rock erswitch tothe | position.
X To switch therear interior lighting on/
off: press theu button .
X To switch thereading lampson/off:
press thep button . Crash-
responsive emergency lighting
The interior lighting isactivated automatically
if the vehicle isinvolved inan accident .
X To switch offthe crash- responsive
emergency lighting:pressthehazard
warning lampbutton .
or
X Lock andthen unlock thevehicle usingthe
Smart Key. Replacing
bulbs Import
antsafety notes
Xenon bulbs If
your vehicle isequipped withXenon bulbs,
you can recogn izethis bythe following: the
cone oflight from theXenon bulbsmoves
from thetop tothe bottom andback again when
youstart theengine. Forthis tobe
observed, thelights mustbeswitched on
before startingthe engine. G
DANGER Xenon
bulbscarryahigh voltage. Youcould
get anelectric shockandbeseriously oreven
fatally injured ifyou touch theelectric
cont acts onXenon bulbs.Therefore, never
remove thecover fromXenon bulbs.
Do not change Xenonbulbsyourself, buthave
them replaced ataquali fiedspecialist
workshop whichhasthenecessary specialist
knowledge andtools tocarry outthework
required.
Mercedes-B enzrecommen dsthat youusean
authorized Mercedes-B enzCenter forthis
purpose. Inparticular, workrelevant tosafety
or on safety-related systemsmustbecarried
out ataquali fiedspecialist workshop.
Bulbs andlamps areanimportant aspectof
vehicle safety.Youmust therefor emake sure
that these functioncorrec tlyatall times.
Have theheadlamp settingcheck edregularly .
Other bulbs There
arebulbs otherthantheXenon bulbs
that youcann otreplace. Replaceonly the
bulbs listed (Ypage 115). Havethebulbs that
you cann otreplace yourself changed ata
quali fiedspecialist workshop.
Mercedes-B enzrecomm endsthatyouusean
authorized Mercedes-B enzCenter forthis
purpose. Inparticular, workrelevant tosafety
or on safety-related systemsmustbecarried
out ataquali fiedspecialist workshop.
If you require assistance changingbulbs,
consult aquali fiedspecialist workshop.
Do not touch theglass tubeofnew bulbs with
your bare hands. Evenminor contamination
can burn intotheglass surface andreduce
the service lifeofthe bulbs. Always usealint-
free cloth oronly touch thebase ofthe bulb
when installing.
Only usebulbs ofthe correc ttype. 114
Rep
lacingbul bsLights an dwindshield wipers

4
e Toswitch offinter mittentwiping
5 b Towipe withwasher fluid
X Turn theSmart Keytoposition 1or 2in the
ignition lock.
X Slide switch :onthe combinat ionswitch
up ordown tothe appropriate position.
When therear window wiperisswitched on,
the icon appears inthe instr ument cluster. Replacing
thewiper blades
Impor tantsafety notes G
WARNIN
G For
safety reasons, switchoffthe windshield
wipers andremove thekey from theignition
lock before changin gthe wiper blades
(vehicles withKEYLE SS-GO: make surethat
the on-board electronicsare instate 0).
Otherwise, thewiper motor couldbeswitched
on suddenly andcause injury.
! Toavoid damaging thewiper blades,
make surethatyoutouch onlythewiper
arm ofthe wiper.
! Never openthehood ifawindshield wiper
arm hasbeen folded awayfromthe
windshield.
Never foldawindshield wiperarmwithout
a wiper bladebackontothe windshield/
rear window.
Hold thewindshield wiperarmfirmly when
you change thewiper blade. Ifyou release
the windshield wiperarmwithout awiper
blade anditfalls ontothe windshield, the
windshield maybedamaged bythe force of
the impact.
Mercedes- Benzrecomm endsthatyouhave
the wiper blades replaced byaq ualifi ed
spec ialist workshop,e.g. at an auth orized
Mer cedes- BenzCent er. Changing
thewindshield wiperblades Removing
thewiper blades
X Remove theSmart Keyfrom theignition
lock.
X Fold thewiper armaway fromthe
windshield. X
Firmly pressrelease knob : and pullthe
wiper bladeupwards fromthewiper armin
the direct ionofthe arrow.
Installing thewiper blades
X Position thenew wiper bladeinthe retain er
on the wiper armandslide itint oplace in
the opposite directiontothe arrow.
The wiper bladeaudibly engages.
X Make surethatwiper bladeisseated
corr ectly.
X Fold thewiper armback ontothe
windshield.
Repla cingtherear window wiperblade Removing
thewiper blade G
WARN
ING The
wiper armcould beset inmotion and
injur eyou ifthe wiper isswitch edon.
Remove thekey from theignition lockbefore
replacing thewiper blade. Windsh
ieldwipers
119Lights and windshield wipers Z

Useful
information
i This
Operat or'sManual describesall
models andallstan dard andoption al
equipment ofyour vehicle available atthe
time ofpublication ofthe Operat or's
Manual. Country-specificdiffer encesare
possible. Pleasenotethat your vehicle may
not beequipped withallfeature s
descr ibed. Thisalso applies tosafet y-
related systemsand func tions. i
Please
readtheinfor mation onqualified
specialist workshops(Ypage 25). Overview
ofclimat econtrol systems Impor
tant safet ynotes G
WARN
ING Sever
econ dition s(e.g. strong airpollution )
may require replacem entofthe filter before
its scheduled replacementinterval. Aclogged
filt er will reduc ethe airvolume tothe interior
and thewindows couldfogup,impairin g
visibilit yand endan geringyou and others.
Have ablock edfilterreplac edataMerc edes-
Ben zCent eras soon aspossible. G
WARN
ING Follow
therecom mended settings forheating
and cooling givenonthe following pages.
Other wise, thewindows couldfogup,
impairing visibilityandendanger ingyou and
other s.
Autom aticclimate control controls the
temper atureandthehumidity ofthe vehicle
int erior andfilters outundesirable
substanc esfrom theair.
Autom aticclimate control isonly operation al
when theengine isrunn ing9
.O ptimum
operation isonly achieved ifyou drive withthe
side windows andsliding sunroof /panorama
roof with power tilt/sliding panelclosed. i
Vent
ilate thevehicle forabrief period
during warmweather, e.g.using the
con venien ceopenin gfeature (Ypage 86).
This willspeed upthe coolin gproces sand
the desired vehicleinterior temper ature
will bereached morequickly. i
The
integrated filtercanfilter outmost
partic lesofdust andcomplet elyfilter sout
pollen. Aclogged filterreduc esthe amoun t
of air supplied tothe vehic leint erior .For
this reason, youshould alwaysobserve the
inter valforreplacing thefilter, which is
specified inthe Servic eBooklet .Asit
depends onenvironmen talconditions, e.g.
heavy airpollu tion, theinterval maybe
shorter thanstated inthe Service Booklet.
9 The residua lheat function canonly beactivated/deactivated whentheignition isswitched off. 122
Overview
ofclimat econ trol systemsClimate control

Note
son using 3-zo neauto matic
cl imate contro l
Th efol lowi ng conta insnote sand
rec omm endations onoptim um opera tiono f
auto maticclim atecontrol.
R Ac tivate clim atecontrol usin gth eà and
¿ buttons .T he indicator lampsinthe
à and¿ buttons lightup.
R In automatic mode,youcan also usethe
ñ button toset aclimate mode
(FOCUS/ME DIUM/DIFFUSE). The
MEDI UMlevel isrecommen ded.
R Set thetemperature to72 ‡(22 †).
R Only usethe"defrosting" functionbriefly
until thewindshield isclear again.
R Only use"air-recirculation" modebriefly,
e.g. ifthere areunpleasa ntoutside odors
or when inatunn el.The windows could
otherwise fogupas, inair-recirculation
mode, nofresh airisdrawn intothevehicle.
R Use theZONE functiontoadopt the
temperature settingson the driver's side
for the front -passenger sideandtherear
compartmen taswell .The indicator lampin
the á button goesout.
R Use theresidual heatfunct ionifyou want
to heat orvent ilate thevehicle interior
when theignition isswitched off.The
"residu alheat" functioncan only be
activated ordeactivated withtheignition
switched off. Operat
ingthe climate controlsystem Activating/deactivating
climate
control
Import antinformat ion G
WARNING When
theclimate controlsystem is
deactivated, theoutside airsupply and
circulation arealso deactivated. Onlychoose
this settin gfor ashort time.Otherwise the windows
couldfogup,impairing visibilityand
endangering youand others. i
Switch
onclimate controlprimarily using
the à button (Ypage 129).
In the rear compartmen t,you can also switch
climate controlonand offusing theà and
^ buttons.
Activating/deactivating X
Turn theSmartK eytoposition 2in the
ignition lock.
X To switch on:press theà button.
The indicator lampinthe à button lights
up. Airflow andairdistribution aresetto
automatic mode.
or
X Press the^ button.
The indicator lampinthe ^ button goes
out. Thepreviously selectedsettingscome
into effect again.
X To switch off:press the^ button.
The indicator lampinthe ^ button lights
up. Activating/deactivating
thecool ing
with airdehum idification function
Import antinformat ion The
cooling withairdehumidi ficationfunction
is only availa blewhen theengine isrunning.
The airinside thevehicle iscooled and
dehumidi fiedaccording tothe temperature
selected. G
WARNING If
you switch offthe cooling function,the
vehicle willnotbecooled whenweather
condition sare warm. Thewindows canfogup
more quickly. Window foggingmayimpair
visibili tyand endanger youand others.
Condensation maydripfrom theunderside of
the vehicle whenitis in cooling mode.Thisis 128
Operat
ingthe climate controlsystemClimate control

norm
aland notasign tha tther eis a
ma lfunctio n. i
The
cooling with aird ehumidification
func tion uses refriger antR134a. This
coolant doesnotcontain
chlorof luorocarbon s,and therefore does
not damage theozon elayer.
Activating/d eactivating X
To activa te:press the¿/Á button.
The indicat orlamp inthe ¿/Á
button lightsup.
X To deactiva te:press the¿/Á
button .
The indicat orlamp inthe ¿/Á
button goesout.Thecooling withair
dehumidification function hasadelayed
switch -offfeature.
Problems withthecooling withair
dehum idificat ionfunction When
youpress the¿/Á button,the
indicat orlamp inthe button flashes three
times orremains off.You cannolonger switch
on the cooling withairdehumidification
func tion.
X Consult aqualified specialist workshop. Sett
ingclimat econtrol toaut omat ic G
WARN
ING If
you switch offthe cooling function,the
vehicle willnotbecooled whenweather
con ditions arewarm. Thewindows canfogup
more quickly. Window foggingmayimpair
visibility andendanger youand other s.
In automatic mode,thesettemper atureis
maint ained automatic allyatacon stan tlevel.
The system automatic allyregulates the
temper atureofthe dispensed air,the airflow
and theairdistribut ion.
Autom aticmode willachieve optimal
operation ifcooling withairdehumidification is
also activat ed.Ifdesired, coolingwithair
dehumidification canbedeactivat ed.
In the rear compart ment,you can also switch
climate control forthe rear seats toautomatic
mode usingtheà button .
X Turn theSmart Keytoposition 2in the
ignition lock.
X Set thedesired temperature.
X To activa te:press theà button .
The indicat orlamp inthe à button lights
up. Autom aticairdistribut ionand airflow
are activ ated. i
Autom
aticclimate control: when
automatic modeisactivat ed,you can
select aclimate modesetting
(Y page 129).
X To switch off:press the_ button .
or
X Press theI orK button .
The indicat orlamp inthe à button goes
out. Adju
sting theclimat emode settings
(AIR FLOW)
This function isonly available withautomatic
climate control.
The climate control settings areespecially
effec tiveathigh temper atures.
You canselect thefollowing climatecontrol
sett ings inautomatic mode:
FOCUS highairflow thatisset slightly
cooler
MED IUM medium airflow,standard setting
DIF FUS Elow airflow thatisset slightly
warmer andwith alower rateof
airflow Opera
tingtheclimate controlsystem
129Climate control Z

X
Turn theSmart Keytoposition 2in the
ignition lock.
X Press theà button .
X Press theñ button repeatedly untilthe
desired climatemodeappears inthe
display . Setting
thetemp erature
Climate control Differ
enttemperat urescanbeset forthe
driver's andfront-passenger sides.
X Turn theSmart Keytoposition 2in the
ignition lock.
X To increase/reduce: turncontrols:and
B clock wiseorcount erclock wise
(Y page 123).
Only change thetemperat uresettingin
small increm ents.Start at72 ‡(22 †).
3-zone automat icclimate control Automat
icclimate controlzones
You canselect different temperat uresett ings
for the driver's andfront-passenger sidesas
well asfor the rear compart ment.
X Turn theSmart Keytoposition 2in the
ignition lock.
X To increase/reduce thetemp eraturein
the front :turn controls:and B clock
wiseorcount erclock wise
(Y page 126).
Only change thetemperat uresettingin
small increm ents.Start at72 ‡(22 †).
X To increase/reduce thetemp eraturein
the rear compar tment using thefront
control panel:presstheá button .
The indicator lampinthe á button goes
out.
X Turn control: clock wiseor
count erclock wise(Ypage 126).
Only change thetemperat uresettingin
small increm ents.Start at72 ‡(22 †).
The temperat uresettingforthe driver's
side isadopted forthe rear compart ment
and thefron t-passenger side.
X To increase/decrease therear
compar tment temp eratureusing the
rear control panel:turncontrolM onthe
rear controlpanel clockwiseor
count erclock wise(Ypage 126).
Only change thetemperat uresettingin
small increm ents.Start at72 ‡(22 †). Setting
theairdistr ibution
Front control unit:
P Directsair through thecent ervent s.
O Directsthe airflow through the
footwell airvent s
S Directsthe airflow through thecent er
and footwell vents.
¯ Directsthe airflow through the
defrost ervent s
b Directsthe airflow through the
defrost erand cent ervent s10
a Directsthe airflow through the
footwell anddefrost ervent s
_ Directsthe airflow through the
defrost er,cent erand footwell air
vent s10
10 For Canada only. 130
Opera
tingtheclimate controlsystemClimate control

Rear
control panel:
M Directsthe airflo wthrou ghthe rear
center andrearsid eairvents.
O Directsthe airflo wthrou ghthe
footw ellai rv ent s i
Using
therear control panel, youcan also
activat eboth airdistribut ionposition s
simultaneously. Inorder todo this, press
both airdistribut ionbutton s.The airisthen
routed through allrear airvent s. i
Regardless
ofthe airdistribut ionsett ing,
airflow isalway sdirect edthrough theside
air vent s.The side airvent scan only be
closed whenthecontrols onthe side air
vent sare turn eddownwards.
X Turn theSmart Keytoposition 2in the
ignition lock.
X Front control panel:pressthe_
button repeatedly untilthedesired symbol
appears inthe display.
X Rear control panel:presstheM and/
or O button . Sett
ingthe airflow
X Turn theSmart Keytoposition 2in the
ignition lock.
X To increase: presstheK button .
X To redu ce:press theI button . i
You
canuseautomatic climatecontrol to
set the airflow inthe rear compart ment
separately. Switching
theZONE function on/off
X To switch on:press theá button .
The indicat orlamp inthe á button lights
up.
Dual-z oneautomatic climatecontrol: the
temper aturesettingforthe driver's sideis not
adopted forthe fron t-passenger side.
The temper atureofthe fron t-passenger
side isadopted forthe rear compart ment.
Autom aticclimate control: the
temper aturesettingforthe driver's sideis
not adopted forthe fron t-passenger side
and therear compart ment.
When thebutton sor con trols for
temper ature,airflow orair distribut ionare
activat ed,the temper aturesettingforthe
driver's sideisnot adopted forthe other
climate control zones.
X To switch off:press theá button .
The indicat orlamp inthe á button goes
out.
The temper aturesettingforthe driver's
side isadopted forthe fron t-passenger side
and therear compart ment. Defrosting
thewindshield
You canusethis func tion todefrost the
windshield ortodefrost theinside ofthe
windshield andtheside windows. i
You
should onlyselect thedefrost ing
func tion until thewindshield isclear again.
X Turn theSmart Keytoposition 2in the
ignition lock.
X To activa te:press the¬ button .
The indicat orlamp inthe ¬ button lights
up.
The climate control system switchestothe
following functions:
R cooling withairdehumidification on11
R high airflow 12
R high temper ature12
R air distribut iontothe windshield and
fron tside windows
R air-r ecirculat ionmode off
11 Only withenginerunn ing.
12 Depe ndingon the outs idetem perat ure. Oper
ating theclima tecontr olsyst em
131Climate control Z

X
To switchof f:pre ssthe ¬ button.
The indicator lamp inthe ¬ button goes
ou t.The previouslysel ecte dsettings come
int oeffec tagain. Thecooling withair
dehumidification functionremains on.Air-
recirculation moderemains deactivated.
or
X Press theà button .
The indicator lampinthe ¬ button goes
out. Airflow andairdistribution aresetto
automatic mode.
or
X Turn controls:orB clock wiseor
count er-clockwise (Ypage 123),
(Y page 123).
or
X Press theK orI button . Switching
maximumcool ingMAX
COOL on/off
The MAX COOL functionisonly availa blein
vehicles forthe USA .
MAX COOL isonly operational whenthe
engine isrunnin g.
When youactivate MAXCOOL, climate
cont rolswitches tothe following functions:
R maximum cooling
R maximum airflow
R air-recirc ulationmodeon
X To activat e:press theÙ button .
The indicator lampinthe button lightsup.
X To deactivat e:press theÙ button
again.
The indicator lampgoesout.Thepreviously
selected settings come intoeffect again. Defrosting
thewindows
Windows foggeduponthe inside X
Act ivate the¿/Á coolingwithair
dehumidification function.
X Act ivate automatic modeÃ.
X Ifthe windows continue tofog up,activate
the defrostin gfunct ion(Ypage 131). i
You
should onlyselect thissettinguntil
the windshield isclear again.
Windows foggeduponthe outside X
Act ivate thewindshield wipers.
X Press the_ button repeatedly untilthe
P orO symbol appears inthe
display . i
You
should onlyselect thissettinguntil
the windshield isclear again. Rear
window defroster
Activating/deactivat ing G
WARNING Any
accumulation ofsnow andiceshould be
removed fromtherear window beforedriving.
Visibility couldotherwise beimpaired,
endangering youand others.
The rear window defroster hasahigh current
draw. Youshould therefor eswitch itoff as
soon asthe window isclear asitonly switches
off automatically afterseveral minutes.
If the battery voltage istoo low, therear
window defroster mayswitch off.
X Turn theSmart Keytoposition 2in the
ignition lock.
X Press the¤ button .
The indicator lampinthe ¤ button lights
up orgoes out. 132
Opera
tingtheclimate controlsystemClimate control

Problems
withtherear window
defroster The
rear window defroster hasdeactivated
itself prematurely orcannot beactivated.
X Switch offany consumers thatarenot
required, e.g.reading lampsorinterior
lighting.
When thebattery issufficiently charged,
the rear window defroster isactivated
again automatically. Activating/deactivating
air-
recirculation mode
You candeactivate theflow offresh airif
unpleasant odorsareenterin gthe vehicle
from outside. Theairalready insidethe
vehicle willthen berecirculated.
The operation ofair-recirculation modeisthe
same forallcont rolpanels. G
WARNING Fogged
windows impairvisibility,
endangering youand others. Ifthe windows
begin tofog onthe inside, switching offthe
air recirculation modeimmediately should
clear interior window fogging. Ifinterior
window foggingpersists, makesuretheair
condition ingisactivated, orpress the¬
button.
X Turn theSmartK eytoposition 2in the
ignition lock.
X To activate: pressthed button.
The indicator lampinthe d button lights
up. i
In
the event ofhigh pollu tionlevels 13
or at
high outside temperatures, air-
recirculation modeisautomatically
activated. Whenair-recirculation modeis
activated automatically ,the indicator lamp
in the d button isnot lit.
Outside airisadded afterabout 30
minutes. X
To switch off:press thed button.
The indicator lampinthe d button goes
out. i Air-r
ecirculation modedeactivates
automatically :
R after approximately fiveminutes if
outside temperatures areless than about
41 ‡(5 †)
R after approximately fiveminutes if
cooling withairdehumidi ficationis
deactivated
R after approximately 30minutes ifoutside
temperatures areover about
41 ‡(5 †)
R ifyou press the¿/Á buttonand
switch oncooling withair
dehumidi fication Activating/deactivating
theresidual
heat function
The residual heatfunct ionisonly availa blein
Canada
It is possible tomake useofthe residual heat
of the engine tocont inue heating the
stationary vehicleforupto30 minutes after
the engine hasbeen switched off.The heating
time depends onthe temperature thathas
been set. i
The
blower willrun atalow speed
regardless ofthe airflow setting. i
If
you activate theresidual heatfunct ion
at high temperatures, onlythevent ilation
will beactivated. Theblower runsat
medium speed.
X Turn theSmartK eytoposition 0in the
ignition lockorremove it.
X To activate: presstheÌ/Á button.
The indicator lampinthe Ì/Á
button lightsup.
13 Automatic climatecontrolonly. Operat
ingthe climate controlsystem
133Climate control Z

X
To dea ctivate :pre ssthe Ì/Á
bu tton.
The indicator lamp inthe Ì/Á
bu tton goesou t. i Re
sidu alhea tisdeactivated
automaticall y:
R after about30 minutes
R when theignition isswitched on
R ifthe battery voltage drops
R ifthe coolant temperature istoo low Setting
theairvents Importa
ntsafety notes G
WARNING When
operating theclimate control,the air
that enters thepassenger compartment
through theairvents canbevery hotorvery
cold (depending onthe settemperature). This
could cause burnsorfrostbite tounprotected
skin inthe immediate areaofthe airvents.
Always keepsufficient distancebetween
unprotected partsofthe body andtheair
vents. Ifnecessary, usetheairdistribution
adjustment todirect theairtoair vents inthe
vehicle interior thatarenot inthe immediate
area ofunprotected skin.
In order toensure thedirect flowoffresh air
through theairvents intothevehicle interior,
please observe thefollowi ngnotes:
R keep theairinlet grille onthe hood andin
the engine compartment onthe front -
passenger sidefreeofblockages, suchas
ice, snow orleaves.
R never covertheairvents orair intake grills
in the vehicle interior. i
For
virtually draft-free ventilation, adjust
the sliders ofthe airvents tothe cent er
position. Setting
thecenter airvents :
Center airvent, left
; Center airvent, right
= Center ventthumbwheel, right
? Center ventthumbwheel, left
X To open/c lose:turnthumbwheels =
and ?tothe right orleft. Setting
theside airvents X
To open/c lose:turn thumbwheel =upor
down. Setting
theglove boxairvent
When automatic climatecontrolisactivated,
the glove boxcanbecooled, forinstance to
cool itscont ents. Thelevel ofairflow depends
on the airflow andairdistribution settings.
At high outside temperatures, opentheair
vent andactivate the"cooling withair
dehumid ification" function. 134
Setting
theairventsClimate control