2004 MERCEDES-BENZ G500 cooling

50 Getting startedDrivingProblems while driving
The engine runs erratically and misfires

An ignition cable may be damaged.


The engine electronics may not be op-
erating properly.


Unburned gasoline may have entered
the catalytic converter and damaged it.

Give very little gas.

Have the problem repaired by an au-
thorized Mercedes-Benz Light Truck
Center as soon as possible.The coolant temperature is over 248°F
(120°C)
The coolant is too hot and is no longer
cooling the engine.

Stop the vehicle as soon as possible
and turn off the engine. Allow engine
and coolant to cool down.

Check the coolant level and add cool-
ant if necessary (
page 232).In case of accident
If the vehicle is leaking gasoline:

Do not start the engine under any cir-
cumstances.

Notify local fire and/or police authori-
ties.
If the extent of the damage cannot be de-
termined:

Notify an authorized Mercedes-Benz
Light Truck Center.
If no damage can be determined on the


major assemblies


fuel system


engine mount

Start the engine in the usual manner.
iExcessive coolant temperatures trigger
a warning message in the multifunction
display (
page 269).

157 Controls in detail
Climate control
Climate control panel
1
Windshield defroster air vents
2
Center air vent, adjustable
3
Thumbwheel for center air vent
4
Side air vent, adjustable
5
Side defroster air vent, fixed
6
Thumbwheel for side air vent
7
Footwell air vents
8
Climate control paneliFor draft-free ventilation, move the slid-
ers for the center air vents to the mid-
dle position.
1
Air volume
2
Temperature control, left
3
Temperature control, right
4
Air distribution control
5
Rear window defroster (
page 155)
6
AC cooling on / off (AC
OFF
)
Residual engine heat utilization
(REST)
7
Air distribution and air volume (auto-
matic mode)
8
Air recirculation
9
Defrosting

158 Controls in detailClimate controlThe climate control is operational whenev-
er the engine is running. You can operate
the climate control system in either the au-
tomatic or manual mode. The system cools
or heats the interior depending on the se-
lected interior temperature and the cur-
rent outside temperature.Nearly all dust particles, pollutants and
odors are filtered out before outside air en-
ters the passenger compartment through
the air distribution system.
The air conditioning will not engage (no
cooling) if the AC
OFF
mode is selected
(
page 162).
Setting the temperature
Use temperature controls2 and3 to
separately adjust the air temperature on
each side of the passenger compartment.
You should raise or lower the temperature
setting in small increments, preferably
starting at 72°F (22°C).
Warning!
G
When operating the automatic climate con-
trol, the air that enters the passenger com-
partment through the air vents in the
footwell can be very hot or very cold (de-
pending on the set temperature). This may
cause burns or frostbite on unprotected skin
in the immediate area of the air vents. Al-
ways keep sufficient distance between un-
protected parts of the body and the footwell
air vents. If necessary, change the air flow
using the air distribution controls to direct
the air away from the footwell air vents
(page 159).
Warning!
G
Follow the recommended settings for heat-
ing and cooling given on the following pag-
es. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
iIf the vehicle interior is hot, ventilate
the interior before driving off.
Keep the air intake grille in front of the
windshield free of snow and debris.iWhen operating the climate control
system in automatic mode, you will
only rarely need to adjust the tempera-
ture, air volume and air distribution.

162 Controls in detailClimate controlDeactivating the climate control system
Deactivating
Set the air volume control switch to
position0.
Reactivating

Set the air volume control switch to any
speed.
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.
Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.
Press button°.
The indicator lamp on the button°
comes on.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air conditioner.

Press button° again.
The indicator lamp on the button°
goes out.
The air conditioner uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.
iCondensation may drip out from under-
neath the vehicle. This is normal and
not an indication of a malfunction.
!If the° button on the climate con-
trol panel starts to blink, this indicates
that the air conditioner is losing refrig-
erant. The compressor has turned itself
off. The air conditioner cannot be
turned on again.

Have the air conditioner checked at
the nearest authorized
Mercedes-Benz Light Truck Center.

233 Operation
Engine compartment
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
1Cap

Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap to the left and
remove it.

Check coolant level.
The coolant level is correct if the level

for cold coolant: is level with the
mark on the reservoir


for warm coolant: is approx. 0.6 in
(1.5 cm) higher

Add coolant as required.

Replace and tighten cap until you hear
it click a few times.
For more information on coolant, see
“Coolants” (
page 336).
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature display in-
dicates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if engine temperature is above
194°F (90°C). Allow engine to cool
down before removing cap. The coolant
reservoir contains hot fluid and is under
pressure.


Using a rag, slowly open the cap approx-
imately
1⁄2turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.

268 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.

Add coolant (
page 232).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Light
Truck Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat causing serious
engine damage.
Observe the coolant temperature dis-
play (
page 112).

270 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
Ï
COOLANT
STOP, ENGINE OFF!
The poly-V-belt could be broken.

Stop immediately and check the
poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
s u l t i n d a m a g e t o t he e n g i n e . N ot i f y a n
authorized Mercedes-Benz Light Truck
Center.
If it is in order:

Do not continue to drive the vehicle
with this message displayed. Doing so
could result in serious engine damage
that is not covered by the
Mercedes-Benz Limited Warranty.
COOLANT
VISIT WORKSHOP!
The cooling fan for the coolant is malfunc-
tioning.

Observe the coolant temperature dis-
play (
page 112).

Have the fan replaced as soon as pos-
sible.

334 Technical dataFuels, coolants, lubricants, etc.Engine oils
Engine oils are specifically tested for their
suitability in our engines. Therefore, use
only engine oils recommended by
Mercedes-Benz. Information on approved
engine oils is available in the Factory Ap-
proved Service Products pamphlet, or at
your authorized Mercedes-Benz Light
Truck Center.Please follow the FSS and Service Booklet
recommendations for scheduled oil chang-
es. Failure to do so could result in engine
damage not covered by the
Mercedes-Benz Limited Warranty.
Model
Capacity
Fuels, coolants, lubricants, etc.
Cooling system
approx. 12.7 US qt (12.0 l)
MB Anticorrosion/Antifreeze
Air conditioning system
R-134a refrigerant and
special PAG lubricant oil (never R-12)
Windshield/rear window washer system
and headlamp cleaning system
approx. 7.9 US qt (7.5 l)
MB Windshield Washer Concentrate
and water
1
1Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing point or MB Windshield Washer Concentrate “S” and commercially available
premixed windshield washer solvent / antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 339).
!Always check the oil filler cap
(page 232) for important informa-
tion pertaining to the engine oil need-
ing to meet a specific Mercedes-Benz
specification (e.g. MB 229.5). If such
information is printed on the oil filler
cap, only use an engine oil from the list
of approved engine oils in the Factory
Approved Service Products pamphlet
that meets the specification indicated
on the oil filler cap.
Using engine oils of other specification
may cause the FSS to incorrectly deter-
mine the next service interval and will
result in engine damage not covered by
the Mercedes-Benz Limited Warranty.