engine overheat MERCEDES-BENZ G-CLASS SUV 2018 Owners Manual

&
WARNING Risk of accident due to
unsuitable foot we ar
Operating the pedals may be impaired by
we aring unsuitable foot we ar, e.g.:
R plat form shoes
R high-heeled shoes
R slippers #
Alw ayswe ar suitable foot we ar when
driving so that you can operate the ped‐
als safel y. &
WARNING Risk of accident when switch‐
ing off the ignition when driving
If yo u swit choff the ignition while driving,
saf ety functions are restricted or no longer
av ailable. This may af fect the po werst eering
sy stem and the brake forc e boosting, for
ex ample.
Yo u will then need touse considerably more
fo rc eto steer and brake. #
Do not switch off the ignition while driv‐
ing. &
DANG ER Risk of fata l injuries due to
ex haust gases
Combustion engines emit poisonous exhaust
ga ses such as carbon monoxide. Inhaling
th ese exhaust gases is hazardous tohealth
and can lead topoisoning. #
Never lea vethe engine running in an
enclosed space wi thout suf ficient venti‐
lation. &
WARNING Risk of skidding and of an
accident due toshifting down on slippery
ro ad sur faces
If yo u shift down on slippery road sur faces to
inc rease the engine braking ef fect, the drive
wheels may lose traction. #
Do not shift down on slippery road sur‐
fa ces toinc rease the engine braking
ef fect. &
DANG ER Risk of fata l injuries due topoi‐
sonous exhaust gases
If th eta ilpipe is bloc ked or suf ficient ventila‐
tion is not possible, poisonous exhaust gases
such as carbon monoxide may enter theve hi‐
cle. This is the case, forex ample, if theve hi‐
cle is stuck in sn ow. #
When the engine or thest ationary
heater are running, keep theta ilpipe
and the area around theve hicle clear of
sno w. #
Open a window on the side of theve hi‐
cle facing the wind toensure an ade‐
qu ate supply of fresh air. &
WARNING Risk of accident due tothe
brake sy stem overheating
If yo u lea veyour foot on the brake pedal
when driving, the brake sy stem may over‐
heat.
This increases the braking dis tance and the
brake sy stem may evenfa il. 14 4
Driving and pa rking

&
WARNING Risk of inju ryfrom fuels
Fu els are poisonous and hazardous to your
health. #
Do not swallow fuel or let it come into
contact with skin, eyes or clo thing. #
Do not inhale fuel vapour. #
Keep children away from fuel. #
Keep doors and windo wsclosed du ring
th ere fuelling process.
If yo u or other people come into contact with
fuel, obser vethefo llowing: #
Immediately rinse fuel off your skin with
soap and water. #
If fuel comes into contact with your
ey es, immediately rinse them thor‐
oughly with clean water.Seek medical
attention immediately. #
Ifyo u swallow fuel, seek medical atten‐
tion immediatel y.Do not induce vomit‐
ing. #
Change immediately out of clo thing that
has come into con tact wi thfuel. &
WARNING Risk offire or explosion from
elect rostatic charge
Electros tatic charge can crea tespar ksand
th ereby ignite fuel vapours. #
Before you open the fuel filler cap or
ta ke hold of the pump nozzle, touch the
me tallic vehicle body.
This dischar ges any electros tatic charge
th at may ha vebuilt up. #
Do not get into theve hicle again during
th ere fuelling process.
Otherwise, electros tatic charge could
build up again. &
WARNING Risk offire from fuel mixture
Ve hicles with a diesel engine:
If yo u mix diesel fuel with petrol, theflash
point of the fuel mixture is lo werth an that of
pure diesel fuel. While
the engine is running, component
pa rts in theex haust sy stem may overheat
without warning. #
Neverre fuel using petrol. #
Never mix petrol with diesel fuel. *
NO
TEDama gecaused bythe wrong fuel Ve
hicles with a petrol engine:
Even small amounts of the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using unleaded, sulphu r-free
fuel that con form sto European EN 228,
or an equi valent specification. #
The RONrequ irement is located in the
fuel filler flap.
Fu el of this specification may con tain up to
10 %ethanol. Your vehicle is suitable for use
with E10 fuel. Driving and parking
16 3

1
Cruise cont rol is selec ted
2 Speed is sa ved, cruise control is deactivated
3 Speed is sa ved, cruise control is activated
% The segments extending from the cur rent
st ored speed tothe end of the scale, or to
th e set winter tyre limit, light up in the
speedome ter.
Sy stem limitations
Cruise control may be unable tomaintain the
st ored speed on uphill gradients. The stored
speed is resumed when the gradient evens out.
Change into a lo werge ar in good time on long
and steep downhill gradients. Take particular no
te ofthis when driving a laden vehicle. By
doing so, you will make use of the engine's brak‐
ing ef fect. This relie vesth e load on the brake
sy stem and pr events the brakes from overheat‐
ing and wearing tooqu ickl y.
Do not use cruise control in thefo llowing situa‐
tions:
R In traf fic situations whi chrequ ire frequent
ch anges of speed, e.g. in heavy traf fic, on
winding roads.
R On slippe ryroads. Accelerating can cause
th e drive wheels tolose traction and the
ve hicle could then skid.
R Ifyo u are driving when visibility is poor.
Fu nction of the limi ter
The limiter restricts the speed of theve hicle. To
re duce the speed tothe set speed, the limiter
applies the brakes automaticall y.
Yo u can limit the speed as follo ws:
R Variable: for speed limits, e.g. in built-up
areas.
R Perm anen t:for long-term speed restrictions,
e.g. when driving in winter tyre mode. The
variable limiter is operated using the cor re‐
sponding steering wheel buttons. You can store
any speed abo ve20 km/h up tothe maximum
speed or up tothe set winter tyre limit. You can
also per form settings while theve hicle is station‐
ary if theve hicle has been star ted.
If yo ufa ilto adapt your driving style, the limiter
can neither reduce therisk of an accident nor
ov erride the la wsof ph ysics. It cannot take into
account road, weather or traf fic conditions. The
limiter is only an aid. You are responsible for
maintaining a safe dis tance totheve hicle in
front, forve hicle speed, for braking in good time
and forst ay ing in lane.
Displa ysinthe instrument display
The status of the limiter and thestored speed
are shown in the multifunction displa y. Driving and pa
rking 187

R
Speed limiter (/ page 187)
R Active Dis tance Assi stDISTRONIC
(/ page 190)
* NO
TEEngine dama gedue toexcessively
high engine speeds The engine will be damaged if
you drive with
th e engine in theov errevving range. #
Do not drive wi th the engine in theove r‐
re vving range. The fuel supply is inter
rupted toprotect the
engine when there d mark on there v counter 3
(o ve rrev ving range) is reached.
During no rmal operating conditions, coolant
te mp erature display 4may rise to120 °C. &
WARNING Danger of bu rns when open‐
ing the bonn et
If yo u open the engine bonn etwhen the
engine has overheated or during a fire inthe
engine compartment, you could come into
contact with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. #
Intheeve nt of a fire inthe engine com‐
partment, keep the engine bonn et
closed and call thefire service. Overview of
the but tons on thest eering
wheel 1
¤ Back/Home button (press and hold),
on-board computer
2 Touch Control, on-board co mputer 3
Control panel for cruise control/limiter or
Ac tive Dis tance Assi stDISTRONIC
4 Control panel for multimedia sy stem:
£ LINGU ATRO NIC
ß Displa ysfavo urites
VO L: control knob, adjusts thevo lume or
switches the sound off 8(press)
6 Makes/accepts a call
~ Rejects/ends a call
5 ò Calls up the home screen
6 Touch Control multimedia sy stem
7 % Back button (press and hold) Operating
the on-boa rdcompu ter &
WARNING Risk of di stra ction from infor‐
mation sy stems and communications
equipment
If yo u operate information and communica‐
tion equipment integ rated in theve hicle
when driving, you will be distracted from the
traf fic situation. This could also cause youto
lose control of theve hicle. 226
Instrument Display and on-board computer

fi
ed based on the actual operating conditions
and/or loads.
Examples of arduous operating conditions:
R regular city driving with frequent intermedi‐
ate stops
R mainly short-dis tance driving
R frequent operation in mountainous terrain or
on poor road sur faces
R when the engine is of ten le ftidling for long
periods
R operation in particula rly dusty conditions
and/or if air-recirculation mode is frequently
used
In these or similar operating conditions, ha vethe
interior air filter, engine air cleaner, engine oil
and oil filter etc. changed more frequent ly. The
ty re s must be checked more frequently if the
ve hicle is operated under increased loads. Fur‐
th er information can be obtained at a qualified
specialist workshop. Battery disconnection periods
The ASS
YST PLUS se rvice inter val display
can only calculate the service due da tewhen
th e bat tery is connected. #
Notedown the service due date displa yed on
th e instrument display before disconnecting
th e battery (/ page374). Engine com
partment Opening/closing the bonnet
&
WARNING Risk of accident due todriv‐
ing with the engine bonn etunlo cked
An unloc ked engine bonn etmay open up
when theve hicle is in motion and block your
vie w. #
Never unlock the engine bonn etwhen
driving. #
Before every trip, ensure that the
engine bonn etis loc ked. &
WARNING Risk of accident and inju ry
when opening and closing the engine
bonn et
When opening or closing the engine bonn et,
it may suddenly drop into the end position.
There is a risk of injury for an yone in the
engine bonn et's range of mo vement. #
Only open or close the engine bonn et
when there are no persons in the
engine bonn et's range of mo vement. &
WARNING Danger of bu rns when open‐
ing the bonn et
If yo u open the engine bonn etwhen the
engine has overheated or during a fire inthe
engine compartment, you could come into
contact with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. Maintenance and care
375

#
Park theve hicle on a le vel sur face. #
Check the coolant temp erature display in the
instrument clus ter.
The coolant temp erature must be below
70 °C. #
Slowly turn cap 1anti-clockwise torelease
ove rpressure. #
Continue turning cap 1anti-clockwise and
re mo veit.
The coolant le vel is cor rect:
R ifth e engine is cold, up tomar ker bar 2
R ifth e engine is warm, up to1.5 cm over
mar ker bar 2 #
If necessar y,top up with coolant that has
been appr ovedby Mercedes-Benz.
R Further information on coolant
(/ page 435). To
pping up the windsc reen washer sy stem &
WARNING Risk of bu rns from hot com‐
ponent parts in the engine compartment
Cer tain components in the engine compart‐
ment can be very hot, e.g. the engine, the
ra diator and parts of theex haust sy stem. #
Allow the engine tocool down and only
to uch co mponent parts described in
th efo llowing. &
WARNING Danger of bu rns when open‐
ing the bonn et
If yo u open the engine bonn etwhen the
engine has overheated or during a fire inthe
engine compartment, you could come into
contact with hot gases or other escaping
operating fluids. #
Before opening the bonn et, allow the
engine tocool down. #
Intheeve nt of a fire inthe engine com‐
partment, keep the engine bonn et
closed and call thefire service. &
WARNING ‑ Risk of fire and injury due to
windscreen washer concentrate
Wi ndsc reen washer concentrate is highly
fl ammable. It could ignite if it comes into
con tact wi thhot engine component parts or
th eex haust sy stem. #
Make sure that no windsc reen washer
concentrate spills out next tothefiller
opening. 380
Maintenance and care

While
the engine is running, component
pa rts in theex haust sy stem may overheat
without warning. #
Neverre fuel using petrol in diesel
engines. #
Never mix petrol with diesel fuel. *
NO
TEDama gecaused bythe wrong fuel Even small amounts of
the wrong fuel could
re sult in damage tothe fuel sy stem, the
engine and the emission control sy stem. #
Only refuel using sulphu r-free diesel
fuel that con form sto European stand‐
ard EN 590, or an equivalent specifica‐
tion.
In countries without sulphur-f ree diesel
fuel, refuel using only lo w-sulphur diesel
fuel with a sulphur content less than
50 ppm. #
Vehicles without diesel particulate
fi lter: refuel using only diesel fuel with
a sulphur content less than 500 ppm. Ne
verre fuel with one of thefo llowing fuels:
R petrol
R marine diesel
R heating oil
R pure bio-diesel fuel or vege table oil
R paraf fin or kerosene
If yo u ha veacciden tally refuelled with the
wrong fuel: #
Do not swit ch the ignition on. #
Consult a qualified specialist workshop. The
following compatibility indication for fuel
applies to yourvehicle: 1
For diesel fuel with a maximum of 7% byvol‐
ume bio-diesel (fatty acid me thyl es ter)
Ac cording toEuropean standard EN 1694 2you
can find the compatibility indications at thefo l‐
lowing locations:
R onthe instruction label on the fuel filler flap
R onthe fuel pump or pump nozzle suitable for
yo ur vehicle thro ughout Europe
Information on low outside temperatures
Re fuel your vehicle with as much winter diesel
fuel as possible at the beginning of winter.
Before changing overto winter diesel fuel, the
fuel tank should be em pty, if possible. When first 432
Tech nical da ta

#
Allow the engine tocool down before
yo uto p up the antif reeze. #
Make sure that no antifreeze spills out
next tothefiller opening. #
Thoroughly clean the antif reeze from
component parts before starting the
ve hicle. *
NO
TEDama gecaused byincor rect cool‐
ant #
Only add coolant that has been pre‐
mixed with therequ ired antifreeze pro‐
te ction.
Information on coolant is available at thefo l‐
lowing locations:
R inthe Mercedes-Benz Specification for
Operating Fluids 310.1
- at http://be vo.mercedes-benz.com
- inthe Mercedes-Benz BeVo app
R at a qualified specialist workshop *
NO
TEOverheating at high outside tem‐
peratures If an inapp
ropriate coolant is used, the
engine cooling sy stem is not suf ficiently pro‐
te cted against overheating and cor rosion at
high outside temp eratures. #
Alw ays use coolant appr ovedby
Mercedes-Benz. #
Obser vethe instructions in the
Mercedes-Benz Specifications for Oper‐
ating Fluids 310.1. Ha
ve the coolant regularly replaced at a qualified
specialist workshop.
The proportion of cor rosion inhibitor/antifreeze
concentrate in the engine cooling sy stem should
be:
R a minimum of 50% (antifreeze pr otection
down toappr oximately -37 °C)
R a maximum of 55% (antifreeze pr otection
down to-45 °C) Note
s on windscreen washer fluid Obser
vethe no tes on operating fluids
(/ page 429). &
WARNING ‑ Risk of fire and injury due to
windscreen washer concentrate
Wi ndsc reen washer concentrate is highly
fl ammable. It could ignite if it comes into
con tact wi thhot engine component parts or
th eex haust sy stem. #
Make sure that no windsc reen washer
concentrate spills out next tothefiller
opening. *
NO
TEDama getotheex terior lighting
due tounsuitable windsc reen washer
fl uid Uns
uitable windsc reen washer fluids may
damage the plastic sur face of theex terior
lighting. #
Only use windscreen washer fluids
which are also suitable for use on plas‐ 436
Tech nical da ta

Display messages
Possible causes/consequences and M
MSolutions
# Stop vehicle See Owner's
Manual *T
he battery is no longer being charge d and the battery charge leve l is too lo w.
* NO
TEPossible engine damage if you continue driving #
Do not continue driving under any circum stances. #
Consult a qualified specialist workshop. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions. Do not
continue driving under any circums tances. #
Switch off the engine. #
Consult a qualified specialist workshop.
? *T
hefan mo tor is defective. #
Avoiding high loads on the engine, drive tothe nearest qualified specialist workshop. In doing so, ensure that
th e coolant temp erature display remains below 120 °C.
?
Coolant Stop vehicle
Switch engine off *T
he coolant is too hot. #
Stop theve hicle immediately, paying attention toroad and traf fic conditions, and switch off the engine. &
WARNING Danger of bu rns when opening the bonn et
If yo u open the engine bonn etwhen the engine has overheated or during a fire inthe engine compartment, you
could come into contact wi thhot gases or other escaping operating fluids. Display messages and
warning/indicator lamps 465

Display messages
Possible causes/consequences and M
MSolutions
N permanently active Risk
of vehicle rolling *
While theve hicle is rolling or while you are driving, the transmission has been shif tedto position i. #
Depress the brake pedal tostop and, when theve hicle is stationar y,shift the transmission toposition j. #
Tocontinue your journe y,shift the transmission toposition hork.
Stop vehicle Leave engine
running Wait Transmission
cooling *T
he transmission is overheating. Pulling away may be temp orarily impaired or not possible. #
Pull over and stop theve hicle safely as soon as possible, paying attention toroad and traf fic conditions. Do not
continue driving under any circums tances. #
Lea vethe engine running. #
Wait until the display message disappears before pulling away.
To shift out of P or N,
depress brake and start
engine *
Yo u ha veattem ptedto shift the transmission out of position jori into ano ther transmission position. #
Depress the brake pedal. #
Start the engine.
Apply brake to deselect
Park (P) position *
Yo u ha veattem ptedto shift the transmission out of position jand into ano ther transmission position. #
Depress the brake pedal.
Without changing gear,
consult workshop *T
he transmission is malfunctioning. The transmission position can no longer be shif ted. #
When the transmission is in position h, consult aqualified specialist workshop and do not change the trans‐
mission position. #
For all other transmission positions, park theve hicle safely. #
Consult a qualified specialist workshop. 472
Displaymessa ges and warning/indicator lamps