2012 MERCEDES-BENZ G-CLASS SUV coolant level

ary vehicle for up to 30 minutes after the
engine has been switched off
.The heating
time depends on the coolant temperature and
on the interior temperature that has been set.
i The blower will run at a low speed regard-
less of the airflow setting.
i If you activate the residual heat function
at high temperatures, only the ventilation
will be activated.
X Turn the key to position 0(Ypage 143) in
the ignition lock or remove it.
X To activate: press theÁbutton.
The indicator lamp in the Ábutton lights
up.
X To deactivate: press theÁbutton.
The indicator lamp in the Ábutton goes
out.
i Residual heat is deactivated automati-
cally:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low Auxiliary heating
Important safety notes G
WARNING
Exhaust fumes are produced when the auxili-
ary heating is in operation. Inhaling these
exhaust fumes can be poisonous. You should
therefore switch off the auxiliary heating in
confined spaces without an extraction sys-
tem, e.g. a garage. G
WARNING
When operating the auxiliary heating parts of
the vehicle can get very hot. Make sure that
the exhaust system does not under any cir-
cumstances come into contact with easily
ignitable material such as dry grass or fuels.
The material could otherwise ignite and set the vehicle alight. Choose your parking spot
accordingly.
Operating the auxiliary heating is thus pro-
hibited at filling stations or when your vehicle
is being refuelled. You must therefore switch
off the auxiliary heating at filling stations.
! Operating the auxiliary heating/ventila-
tion draws on the vehicle battery. After you
have heated or ventilated the vehicle a
maximum of two times, drive for a longer
distance.
i Switch the auxiliary heating on regularly
once a month for approximately ten
minutes.
The auxiliary heating heats the air in the vehi-
cle interior without using the heat of the run-
ning engine. The auxiliary heating is operated
directly using the vehicle's fuel. For this rea-
son, the tank content must be at least at
reserve fuel level to ensure that the auxiliary
heating functions.
The auxiliary heating/ventilation automati-
cally adjusts to changes in temperature and
weather conditions. For this reason, the aux-
iliary heating could switch from ventilation
mode to heating mode or from heating mode
to ventilation mode.
You cannot use the auxiliary ventilation to
cool the vehicle interior to a temperature
lower than the outside temperature.
Before switching on X
Turn the key to position 2(Ypage 143) in
the ignition lock.
X Set the temperature.
The auxiliary heating/ventilation can be acti-
vated even when climate control is set to
manual. Optimum comfort can be attained
when the system is set to automatic mode.
Set the temperature to 22 †.
The auxiliary heating/ventilation can be acti-
vated or deactivated using the remote control
or the button on the centre console. 134
Operating the climate control systemClimate control

Problem Possible causes/consequences and
M Solutions
The coolant tempera-
ture display is showing
more than 120 †. A
display message may
also appearint
he mul-
tifunction display and a
warning tone may
sound. The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 293). Observe the warning
notes as you do so and top up the coolant if necessary. If the coolant level is correct, the radiator fan may be faulty. The
coolant is too hot and the engine is no longer being cooled suffi-
ciently.
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. Automatic transmission
Important safety notes
G
WARNING
If the engine speed is above the idling speed
and you engage transmission position Dor
R, the vehicle could pull away suddenly. There
is a risk of an accident.
When engaging transmission position Dor R,
always firmly depress the brake pedal and do
not simultaneously accelerate.
i Bear in mind that the power transmission
between the engine and the transmission
is interrupted when the engine is switched
off. Therefore, to prevent the vehicle from
rolling away, shift the automatic transmis-
sion to position Pand apply the parking
brake when the engine is switched off and
the vehicle is stationary. Selector lever
Overview of transmission positions !
If the engine speed is too high or if the
vehicle is rolling, do not shift the transmis- sion directly from
Dto R, from Rto Dor
directly to P.
Do not open the driver's door while the
vehicle is in motion. At low speeds in trans-
mission position Dor R, park position Pis
otherwise engaged automatically.
The transmission could be damaged. Selector lever
j
Park position
k Reverse gear
i Neutral
h Drive
When you select a transmission position, the
selector lever subsequently returns to its
original position. Automatic transmission
149Driving and parking Z

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