2012 MERCEDES-BENZ G-CLASS SUV engine coolant

Display messages Possible causes/consequences and
M Solutions
b
Remove key You have lef
tthe key in the ignition lock.
X Remove the key from the ignition lock. b
Switch off lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to Ã.Engine
Display messages Possible causes/consequences and
M Solutions
+
Top
up coolant See
Owner's Manual The coolant level is too low.
X
Top up the coolant, observing the warning notes before doing
so (Y page 293).
X Have the coolant system checked at a qualified specialist work-
shop if the coolant needs topping up more often than usual. ? The fan motor is faulty.
X
If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Display messages
237On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions
?
Coolant Stop vehi‐
cle Switch engine
off The coolan
tis too hot.
Aw arning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine
is overheated can cause som efluids which may have leaked into
the engine compartment to catch fire.
Steam fro manoverheated engine can cause serious burns which
can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 163).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 120 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visi taqualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. The poly-V-belt may have torn.
X
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switc hoff the engine.
X Check the poly-V-belt.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is OK:
X Wai tuntil the display message disappears before restarting the
engine .The engine may otherwise be damaged.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. 238
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
Telephone No
service Your vehicle is outside the network provider's transmitter/
receiver range.
X
Wait until the mobile phone operational readiness symbol
appears in the multifunction display. ¥
Top
up washer fluid The washer fluid level in th
ewasher fluid reservoir has dropped
below the minimum.
X Top up the washe rfluid (Y page 294). Key
Displa
ymessages Possible causes/consequences and
M Solutions
Â
Key does not
belong to vehicle You have put the wrong key in the ignitio
nlock.
X Use the correct key. Â
Replace key The key needs to be replaced.
X Visit a qualified specialist workshop. Warning and indicator lamps in the
instrument cluster Warning and indicator lamps over-
view
L Dipped-beam headlamps
(Ypage 105)
T Side lamps (Y page 105)
#! Turn signals (Y page 108)
K Main-beam headlamps
(Ypage 109)
N Foglamps (Y page 106)
R Rear fog lamp (Y page 107)
ü Seat belts (Y page 252)
J Brakes (yellow) (Y page 253)
J Brakes (red) (Y page 253)
! ABS (Ypage 254)
÷ ESP®
(Y page 256)
å ESP®
OFF (Y page 256) 6
SRS (Ypage 259)
; Engine diagnostics
(Ypage 259)
8 Reserve fuel (Y page 260)
? Coolant (Ypage 260)
· Distance warning signal
(Ypage 262)
% Diesel engine: preglow
(Ypage 144)
h Tyre pressure monitor
(Ypage 263) Warning and indicator lamps in the instrument cluster
251On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated when the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. %
On diesel engine vehi-
cles, the preglow indi-
cator lamp does not
light up when the key is
in position
2(Y
page 143). The preglow system is malfunctioning.
X
Visit a qualified specialist workshop immediately. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
start of the scale.
The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Engage the parking brake.
X Consult a qualified specialist workshop. 260
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Engage the parking brake.
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 293).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the coolant temperature is
below 120 †. The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns which
can occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 163).Warning and indicator lamps in the instrument cluster
261On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
X
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 293).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain and stop-start driving. Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion. The distance to the vehicle in front is too small for the speed
selected.
X
Increase the distance. ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
Aw arning tone also
sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Further information on DISTRONIC PLUS (Y page 182).262
Warning and indicator lamps in the instrument clusterOn-board computer and displays

X
If the engine is at normal operating tem-
perature: repeat the measuremen tafter
about five minutes.
X If the engine is not at normal operating
temperature: (e.g. if the engine was only
started briefly) repeat the measurement
after about 30 minutes.
If the Engine oil level Not when engine on message appears:
X Switch off the engine.
X If the engine is at normal operating tem-
perature: wait about five minutes before
carrying out the measurement.
X If the engine is not at normal operating
temperature: e.g. if the engine was only
started briefly, wait approximately
30 minutes before carrying out the meas-
urement.
i If you wish to cancel the measurement,
press the *or& button on the mul-
tifunction steering wheel.
Adding engine oil H
Environmental note
When topping up the oil, take care not to spill
any. If oil enters the soil or waterways, it is
harmful to the environment.
! Do not add too much oil .Ifthe oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic con-
verter. Have excess oil siphoned off. Engine oil cap (example:
G 65 AMG) X
Turn cap :anti-clockwise and remove it.
X Top up with the amount of oil required.
Observe the specifications in the on-board
computer when doing so or fill carefully to the
maximum mark on the oil dipstick.
For further information on engine oil, see
(Y page 345).
i The difference between the minimum
mark and the maximum mark on the oil
dipstick is approximately 2litres.
X Replace cap :on the filler neck and
tighten clockwise.
Make sure that the cap locks securely into
place. Other service products
Checking the coolant level G
WARNING
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has
cooled down. The coolan ttemperature dis-
play must be less than 70 †. Otherwise, you
could be scalded if hot coolant escapes. X
Park the vehicle on a level surface.
Only chec kthe coolant level if the vehicle
is on a level surface and the engine has
cooled down.
X Turn the key to position 2(Ypage 143) in
the ignition lock. Engine compartment
293Maintenance and care Z

from the data show
nhere. You can find the
data applicable to your vehicle on the vehi-
cle's identification plate. Vehicle identification number (VIN)
:
VIN
In addition to the information on the vehicle
identification plate, the vehicle identification
number (VIN) is also stamped onto the chas-
sis on the right when viewed in the direction
of travel. Engine number
The engine number is stamped onto the
crankcase. You can obtain further informa-
tion from any qualified specialist workshop. Service products and capacities
Important safety notes
G
WARNING
When handling, storing and disposing of any
service products, please observe the relevant
regulations, as you could otherwise endanger
yourself and others.
Keep service products away from children.
To protec tyour health, do not allow service
products to come into contact with your eyes
or open wounds. See a doctor immediately if
any service product is swallowed. H
Environmental note
Dispose of service products in an environ-
mentally-responsible manner.
Service products include the following:
R fuels (e.g. petrol, diesel)
R exhaust gas aftertreatmen tadditives, e.g.
AdBlue ®
R lubricants (e.g. engine oil, transmission oil)
R coolant
R brake fluid
R windscreen washer fluid
R climate control system refrigerant
Components and service products must be
matched. Mercedes-Benz recommends that
you use products tested and approved by
Mercedes-Benz .They are listed in this
Mercedes-Ben zOwner's Manual in the appro-
priate section.
You can identify service products approved
by Mercedes-Ben zby the following inscrip-
tions on the container:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations indi-
cate a level of quality or a specification in
accordance with an MB Sheet Number (e.g.
MB 229.5). The yhave no tnecessarily been
approved by Mercedes-Benz.
Further information can be obtained from any
Mercedes-Benz Service Centre or on the
Internet at http://bevo.mercedes-benz.com. Fuel
Important safety notes G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, naked flames, creating
sparks and smoking. Switch off the engine Service products and capacities
341Technical data
Z