2012 MERCEDES-BENZ M-Class ECU

Problem Possible
causes/co nsequences andM Solutions
The
engine cannot be
started usingthe
SmartK ey. The
on-board voltageistoo low.
X Switch offnon- essential consumers, e.g.seat heating orinterior
lighting, andtrytostart theengine again.
If this does notwork:
X Check thestarter battery andcharge itifnecessary
(Y page 338).
or
X Jump-start thevehicle (Ypage 341).
or
X Consult aqual ified specialist workshop. The
engine cannot be
started usingKEYLE SS-
GO. TheSmartK eyisin
the vehicle. Ad
oor isopen. Therefore, theSmart Keycann otbe detect edas
easily .
X Close thedoor andtrytostart thevehicle again. There
isinter ferenc efrom apowerful sourceofradio waves.
X Start yourvehicle withtheSmart Keyinthe ignition lock. Doors
Import
antsafety notes G
WARNIN
G When
leaving thevehicle, alwaysremove the
Smart Keyfrom theignition lock.Always take
the Smart Keywith youand lock thevehicle.
Do not leave children unsupervised inthe
vehicle, evenifthey aresecured inachild
restraint system,anddonot give them access
to an unlocked vehicle.Achild's unsupervised
access toavehicle couldresult inan accident
and/or serious personal injury.Theycould:
R injure themselves onvehicle parts
R be seriously orfatally injured byextrem e
heat orcold
R injure themselves orhave anaccident with
vehicle equipment thatmay stillbein
operation evenaftertheSmartKey has
been removed fromtheignition, suchasthe
seat adjustment ,steering wheel
adjustment ormemory function. If
children openadoor, theycould cause
severe oreven fatalinjury toother persons; if
they getout ofthe vehicle, theycould injure
themselves whendoing soorbe seriously or
even fatally injured byany passing traffic.
Do not expose thechild restraint systemto
direct sunlight. Thechild restraint system's
metal parts, forexample, couldbecome very
hot, andachild could beburned onthese
parts. G
WARNING Do
not carry heavy orhard object sin the
passenger compartmen tor cargo
compartmen tunle ssthey arefirmly secu red
in place .
Unse curedorimp roperlypo sitio ned cargo
incre ases achi ld's ris kof inju ryinthe event
of
R stro ngbra king maneu vers
R sudd en cha nges ofdirecti on
R an acci dent 78
Do
orsOpening/closing

Unlocking
andopening doorsfrom
the inside
You canopen adoor from inside thevehicle
even ifit has been locked.You canonly open
the rear doors frominside thevehicle ifthey
are not secured bythe child- proof locks
(Y page 59).
Only open thedoor when thetrafficsituation
permit s.
If the vehicle waspreviously lockedwith the
Smar tKeyorwith KEYL ESS-GO, openin gthe
vehicle fromtheinside willactiv atethe anti-
thef talarm system .Switc hoff the alarm
(Y page 68). X
Pull door handle ;.
If the door islock ed,lock ingknob : pops
up. The door isunlock edand canbe
opened. Centra
llylocking andunlocking the
vehicle fromtheinside
You cancentrally lockorunlock thevehicle
from theinside.
The central lock ing/ unlock ingbutt ondoes
not lock orunlock thefuel filler flap.
The buttons arelocate don both frontdoors. i
You
cann otunlock thevehicle centrally
from theinside ifthe vehicle hasbeen
locked withtheSmart KeyorKEYLE SS-GO. i
It
is only possible tolock thevehicle
cent rally ifthe front -passenger dooris
closed. X
To unlock: pressbutton :.
X To lock: press button ;.
If all the doors andthetailgate areclosed,
the vehicle locks.
You canopen afront doorfrom inside the
vehicle evenifit has been locked. Onlyopen
the door when thetraffic situation permits.
If the vehicle hasbeen locked withthecent ral
lockin gbutton :
R and theSmart Keyisset toits factor y
sett ing, theentire vehicle isunlocked ifa
front doorisopened fromtheinside
R and theSmart Keyisset toan individual
sett ing, only thefront doorthatisopened
from inside thevehicle isunlocked.
If the vehicle hasbeen locked centrally with
the Smart Keyorwith KEYLE SS-GO, itis not
unlocked whentherelease buttonforthe
cent rallockin gis used. Automa
ticlocking feature
The vehicle locksautomatically whenthe
ignition isswitched onand thewheels ofthe
vehicle areturnin gat as peed ofmore than
9 mph (15km/ h).
You could therefore belock edout when:
R the vehicle isbeing pushed.
R the vehicle isbeing towed.
R the vehicle isbeing testedon a
dynamomet er. Doors
79Opening/closing Z

i
If
you lock thevehicle asdescribe dabove ,
the fuel filler flap isnot locked. Theanti-
theft alarm system isnot armed. Cargo
compartment Important
safetynotes
Do not leavethe SmartKey inthe cargo
compartment. Youcould otherwis elock
you rself out. G
WARNING When
leaving thevehicle ,alw aysremove the
SmartKey fromtheignition lock.Alway stake
the SmartKey withyouand lock thevehicle .
Do not leavechildre nunsu pervised inthe
veh icle, eve nifthey aresecured inachild
restraint system,anddonot give them access
to an unlocked vehicle.Achild's unsupervised
access toavehicle couldresult inan accident
and/or serious personal injury.Theycould:
R injure themselves onvehicle parts
R be seriously orfatally injured byextrem e
heat orcold
R injure themselves orhave anaccident with
vehicle equipment thatmay stillbein
operation evenaftertheSmartKey has
been removed fromtheignition, suchasthe
seat adjustment ,steering wheel
adjustment ormemory function.
If children openadoor, theycould cause
severe oreven fatalinjury toother persons; if
they getout ofthe vehicle, theycould injure
themselves whendoing soorbe seriously or
even fatally injured byany passing traffic.
Do not expose thechild restraint systemto
direct sunlight. Thechild restraint system's
metal parts, forexample, couldbecome very
hot, andachild could beburned onthese
parts. G
WARNING Do
not carry heavy orhard object sin the
passenger compartmen tor cargo compartmen
tunle ssthey arefirmly secu red
in place .
Unse curedorimp roperlypo sitio ned cargo
incre ases achi ld's ris kof inju ryinthe event
of
R stro ngbra king maneu vers
R sudd en cha nges ofdirecti on
R an acci dent G
WAR
NING Ma
kesure the tailgate isclo sed when the
engi neisrunning andwhiled riving. Among
other dange rs,dea dlycarbon monoxide (CO)
gase smay enter vehicleinterior resultingin
unconsciou snessanddeath.
! The tailgate swings upwards andtothe
rear when opened .Therefore, makesure
that there issufficient clearance aboveand
behind thetailgate.
To open thetailgate completely, aminimum
clearance of7.20 ft(2.20 m)above the
gro und isneces sary.
Fo rv ehicles withoutEASY-PACK tailgat e
you can:
R open andcloseth etailg ateman ually from
outs ide
R unloc kthe tailgate frominside withthe
emergency release
For vehicle swith EASY -PACK tailgate you
can:
R close thetailgate manually fromoutside
R open andclose thetailgate automatically
from outside
R open andclose thetailgate automatically
from inside
R limit theopening angleofthe tailgate
R unlock thetailgate frominside withthe
emergency release Cargo
compar tment
81Opening/closing Z

(
Y page 103)in such away that youhave
a good viewofroad andtrafficcon dition s.
X Vehicles withamem oryfunct ion:save
the seat, steeringwheel andexterior mirror
sett ings (Ypage 105). Seats
Impor
tantsafet ynotes G
WARN
ING In
order toavoid possible lossofvehicle
con trol,all seat, head restraint ,steer ing
wheel andrear view mirror adjustm ents,as
well asfasten ingofseat belts, mustbedone
before settingthe vehicle inmot ion. G
WARN
ING Do
not adjust thedriver' sseat while driving.
Adj ustin gthe seat while drivingcould cause
the driver tolose controlof the vehicle.
Never travelin amovin gvehicle withtheseat
backr estinan exc essively reclinedposition as
this canbedangerous. Youcould slideunder
the seat beltinacollision .Ify ou slide under
it, the seat beltwould applyforceatthe
abdomen orneck .This could cause serious or
fatal injuries. Theseat backrest andseat belts
provide thebest restraint whenthewearer is
in aposition thatisas upright aspossible and
seat belts areproperly positioned onthe
body. G
WARNING Your
seatbeltmust beadjusted sothat you
can correct lyfasten yourseatbelt.
Observe thefollowing points:
R adjust theseat backrest untilyour arms are
slightly angledwhenholding thesteering
wheel.
R adjust theseat toacomfort ableseating
position thatstillallow syou toreach the
accelerator/brake pedalsafely. The
position shouldbeasfar back aspossible with
thedriver stillable tooperate the
cont rolsproperly.
R adjust thehead restraint sothat itis as
close tothe head aspossible andthecent er
of the head restraint supports theback of
the head ateye level.
R never placehands undertheseat ornear
any moving partswhile aseat isbeing
adjusted.
Failure todo socould result inan accident
and/or serious personal injury. G
WARNING The
electrically adjustableseatscanbe
operated atany time. Therefore, donot leave
children unattended inthe vehicle, orwith
access toan unlocked vehicle.Achild's
unsupervised accesstoavehicle couldresult
in an accident and/orserious personal injury. G
WARNING Acc
ording toaccident statistics,children are
safer when properly restrained inthe rear
seating positions thaninthe front seating
position. Thus,westron glyrecommen dthat
children beplaced inthe rear seats whenever
possible. Regardlessofseating position,
children 12years oldand under mustbe
seated andproperly securedinan
appropriately sizedinfant restraint ,toddler
restraint ,or booster seatrecommen dedfor
the size andweight ofthe child. Foradditional
information, see"Chil dren inthe vehicle".
Ac hild's riskofserious orfatal injuries is
significantly increasedifthe child restraint s
are not properly securedinthe vehicle and/
or the child isnot properly securedinthe child
restraint . G
WARNING For
your protect ion,drive onlywith properly
positioned headrestraint s.
Adjust thehead restraint sothat itis as close
to the head aspossible andthecent erofthe
head restraint supports theback ofthe head
at eye level. Thiswillreduce thepotent ialfor Seats
95Seats, steering wheel and mirrors
Z

otherwise
notfold inwhen youselect the
"Fold inmirrors whenlockin g"funct ioninthe
on-board computer (Ypage 237).
X Make surethattheSmart Keyisin
position 1in the ignition lock.
X Briefly pressbutton :.
Folding theexterior mirrorsinor out
aut omat ically If
the "Fold inmirrors whenlockin g"funct ion
is activated inthe on-board computer
(Y page 237):
R the exter iormirrors foldinautomatically as
soon asyou lock thevehicle fromthe
outside.
R the exter iormirrors foldoutagain
automatically assoon asyou unlock the
vehicle andthen open thedriver's orfront -
passenger door. i
The
mirrors donot fold outifthey have
been folded inmanually .
Exterior mirrorout ofposition If
an exter iormirror hasbeen pushed outof
position, proceedasfollows:
X Vehicles withoutelectrically folding
exterior mirrors: move theexter iormirror
into thecorrec tposition manually.
X Vehicles withelectrically folding
exterior mirrors: press andhold the
mirror- folding button(Ypage 103)untilyou
hear themirror engage inposition.
The mirror housing isengaged againand
you can adjust theexter iormirrors asusual
(Y page 103). Automa
ticanti-glar emirr ors G
WARNIN
G If
incident lightfrom headlamps isprevent ed
from strikingthe sensor inthe rear-view
mirror, forinstan ce,byluggage piledtoohigh in
the vehicle, themirror's automatic anti-
glare functionwill notoperate.
Inc ident lightcould thenblind you.Thismay
distract youfrom thetraffic conditionsand,
as aresult, youmay cause anaccident .
The rear-view mirrorandtheexter iormirror
on the driver's sideautomatically gointo anti-
glare mode ifthe ignition isswitched onand
incident lightfrom headlamps strikesthe
sensor inthe rear-view mirror.
The mirrors donot gointo anti-glare mode if
reverse gearisengaged orthe interior lighting
is switched on. Park
ingposition forthe exterior
mirr oron the front- passenger side
Setting andstoring theparking position You
canposition thefront -passenger side
exter iormirror insuch away that youcan see
the rear wheel onthat side assoon asyou
engage reverse gear.Youcanstore this
position. X
Make surethatthevehicle isstation aryand
that theSmart Keyisin position 2in the
ignition lock.
X En gage reverse gear.
The exter iormirror onthe front -passenger
side moves tothe preset parking position.
X Use adjustmen tbutton =toadjust the
exter iormirror toaposition thatallows you
to see therear wheel andthecurb.
The parking position isstored. 104
Mirr
orsSeats, steering wheel and mirrors

Aut
oma tic trans mission Imp
ortant safety notes G
WAR
NING It
is dan gerous toshif tthe automatic
transmission outofparking position 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 orsomething. Onlyshiftintogear
when theengine isidling normally andwhen
your right footisfirmly onthe brake pedal. 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. DIREC
TSELECT lever
Over view oftrans mis sion positions The
DIRECT SELECT leve rison the right ofthe
steering column. P
Park position withparking lock
R Reverse gear
N Neutral
D Drive i
The
DIRECT SELECTlever alwaysreturns
to its original position. Thecurrent
transmission positionP,R, Nor Dappea rs
in the transmission positiondisplay
(Y page 145)inthe multifunction display.
Engagin gpar kposit ionP X
Push theDI RECT SELECT lever inthe
direc tiono farrow P. i
The
automatic transmissi onshifts
au tomatical lyinto park position Pifyou
open thedrive r'sdoor when thevehicl eis
stationary ordrivi ngatvery lowspee d,and
the transmissi onisin posi tion Dor R.
! Ifthe engine speedis too high orthe
vehicl eis moving, donot shift the
au tomatic transmissi ondire ctly from Dto
R, from Rto Dor dire ctly toP.T he
automatic transmission couldotherwise be
damaged.
Engaging parkposit ionPau tom atically Park
positionPis autom atically engaged if:
R you switchoff theeng ineusin gth e
Sm artKey and remove theSm artKey, orif
you switchoff theeng ineusin gth eSt art /
St op butt onand open oneof thefron t
door s.
R theHOL Dfun ction (Ypage 179)or
DI STRO NICPLUS(Y page 169)brak es
your vehicle untilit is statio naryand atleast
on eof thefollo wing condition sis fulf illed:
- there isasyst emmalf unction.
- there isasev ere uphill ordown hillslope .
The electric park ingbrak eis then also
applied.
Engag ingreversegear R !
Onlyshif tthe automatic transmission to
R when thevehicle isstationary. 144
Automat
ictransmissionDriving 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

cannot
complete the attem ptedclimb, back it
dow ninr everse gear.
Do not drive along theside ofaslope. The
vehicle mightotherwiserollover. Ifin doing so
the vehicle beginstoshow aten dency toroll,
immediately steerintoaline ofgravity
(straight upordownhill).
Never letthe vehicle rollbackwards inidle.
You may losecontrol ofthe vehicle ifyou use
only theservic ebrake. Forinfor mation on
driving downhill, see"Drivin gdownhill". G
WARN
ING Vehicles
withairsuspension program:Please
be aware thatbyraising thevehicle level,the
cent erofgravity alsorises. Therefor e,alway s
ensure thatthevehicle levelisas low as
possible. Withhigher rideheight theESP®
may activat eearlier incert ainsituation s. G
WARN
ING Do
not reduce thetire inflation pressure
before driving through sand. However, ifyou
do so, remember tocorr ectthe tire inflation
pressure beforecontinuin gyour trip.Drivin g
with reduced tireinflation pressure increases
the risk oflosing control ofthe vehicle and
rolling over.
General notes Read
thissect ioncarefully beforedriving your
vehicle off-road. Practicebydriving overmore
gent leoff- road terrainfirst .
Familiarize yourselfwiththecharact eristics
of your vehicle andthegear shiftoperation
before driving through difficult terrain.
The following drivingsystems arespecially
adapted tooff- road driving:
R Off- road ABS(Ypage 61)
R AIRMA TICpackage (vehiclelevel)
(Y page 180)
R DS R(Downh illSpeed Regulation)
(Y page 208) Observe
thefollowing notes:
R Stop the vehicle beforestartingtodrive
along anoff- road route.
R For vehicles withAIRMA TICpackage:
select avehicle levelthatissuitable forthe
off- road terrain. Make surethere isalway s
sufficien tground clearanc eto preven t
damage tothe vehicle.
R Check thatitems ofluggage andloads are
stowed safelyandarewell secured
(Y page 288).
R Always keeptheengine runningand ingear
when driving onadownhill gradient.
Ac tivat eDS R(Ypage 208).
R Always keepthedoors, tailgate, windows
and sliding sunroof closedwhiledriving.
R Adapt yourspeed tothe terrain. The
rougher, steeperormore rutsonthe
terr ain, theslower yourspeed should be.
R Driv eslowly andatan even speed through
the water. Ensure thatabow wave doesnot
form asyou drive.
R Driv ewith extreme careonunkn ownoff-
road routes wherevisibility ispoor. For
safety reasons ,get out ofthe vehicle first
and survey theoff-road route.
R Look outforobstac lessuch asrock s,holes,
tree stumps andfurrows.
R Check thedepth ofwater before fording
rivers andstreams.
R When fording,do not stop anddonot
switc hoff the engin e.
R On sand, drivequickly tooverc omethe
rolling resistance. Otherwise, thevehicle
could digitself intothe sand.
R Do not jump withthevehicle asthis will
int errupt thevehicle's propulsion.
R Always keeptheengin erunn ingand ingear
when drivingon aslope.
R Do not shift theautomatic transmission to
tran smission positionN. Driving
tips
163Driving and parking Z