Page 239 of 376

239 Operation
Engine compartment
1Coolant expansion tank
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.The coolant level is correct if the level
for cold coolant: reaches the black
top part of the reservoir
for warm coolant: is approx. 0.6 in
(1.5 cm) higher
Add coolant as required.
Replace and tighten cap.
More information on coolant can be found
in the “Technical data” section
(
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 gauge indi-
cates 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
1/2 turn 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.
Page 267 of 376

267 Practical hints
What to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display
Possible cause
Suggested solution
Ï
COOLANT
STOP, ENGINE OFF!
The coolant is too hot.
Stop the vehicle and turn off the
engine.
Only start the engine again after the
message disappears. You could other-
wise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until it
cools down.
!The engine should not be operated with
the coolant temperature above 248°F
(120°C). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.
Page 268 of 376
268 Practical hintsWhat to do if …Display
Possible cause
Suggested 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
inoperative water pump which may
result in damage to the engine. Notify
an authorized Mercedes-Benz Center.
If it is intact:
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
malfunctioning.
Observe the coolant temperature
display.
Have the fan replaced as soon as
possible.
Page 278 of 376
278 Practical hintsWhat to do if …Display
Possible cause
Suggested solution
#
UNDERVOLTAGE
ENGINE ON!
The battery has insufficient voltage and
can no longer supply the convenience
functions such as seat heater*.
Start the engine (
page 44).
UNDERVOLTAGE
SWITCH CONSUMERS OFF!
The battery is malfunctioning.
Have the battery checked at a service
station.
G
VISIT WORKSHOP!
DISPLAY DEFECTIVE
The instrument cluster display is
malfunctioning.
Continue driving with added caution.
Visit an authorized Mercedes-Benz
Center as soon as possible.
±
VISIT WORKSHOP!
DISPLAY DEFECTIVE
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:
Coolant temperature display
Tachometer
Cruise control display
Have the electronic systems checked
by an authorized Mercedes-Benz
Center (
page 259).
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about
1/3
of total reservoir capacity.
Add washer fluid (
page 241).
Page 330 of 376

330 Technical dataFuels, coolants, lubricants etc.
Model
Capacity
Fuels, coolants, lubricants etc.
Front axle
C2404MATIC
C3204MATIC
C3204MATICSport
0.5 US qt (0.46 l)
Hypoid gear oil SAE 85 W 90
Transfer case
C2404MATIC
C3204MATIC
C3204MATICSport
approx. 0.62 US qt (0.59 l)
MB Automatic Transmission Oil
1
Power steering
approx. 1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin CHF 11S)
Front wheel hubs
approx. 2.1oz (60g) each
High temperature roller bearing grease
Brake system
0.5 US qt (0.5 l)
MB Brake Fluid (DOT 4+)
Cooling system
C 230 Kompressor Sport
C240 (all models)
C320 (all models)
C32AMG
approx. 8.5 US qt (8.0 l)
approx. 6.8 US qt (6.4 l)
approx. 6.8 US qt (6.4 l)
approx. 15.3 US qt (14.5 l)
MB 325.0 Anticorrosion / antifreeze agent
Fuel tank
including a reserve of
16.4 US gal (62.0 l)
2.1 US gal (8.0 l)
Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON / 86 MON)Flexible Fuel Vehicle (MY 2003 Mercedes-Benz
C 320 models, except those equipped with
manual transmission or 4MATIC*):
Alternative fuel -- Ethanol fuel (E85)
1MB part no. 001 989 21 03 10
Page 331 of 376
331 Technical data
Fuels, coolants, lubricants etc.
Model
Capacity
Fuels, coolants, lubricants etc.
Air conditioning system
R-134a refrigerant and special PAG lubricant
oil (never R-12)
Windshield washer system:
Without headlamp
cleaning system
With headlamp
cl eaning system*
3.2 US qt (3.0 l)
6.4 US qt (6.0 l)
MB Windshield Washer Concentrate
1
1Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and commercially available
premixed windshield washer solvent/antifreeze for temperatures below freezing. Follow suggested mixing ratios (
page 338).
Page 335 of 376

335 Technical data
Fuels, coolants, lubricants etc.
When switching fuels, make sure that:
Fuel level is below half full.
Fuel level is above reserve (reserve
warning lamp is not lit).
Amount of added fuel is more than
5 gallons (20 liters).
Ignition is off during refill.
Immediately after refueling engine is
started and operated for at least five
minutes.
These precautions and recommendations
are supposed to prevent any difficulties
when starting and operating the engine
which otherwise may be experienced
before the engine has fully adapted to the
different fuel.
If in spite of these recommendations the
engine does not perform properly, adding
more gasoline [at least 3 gallons
(12 liters)] to the fuel may improve the
engine behavior.Cold weather performance
It is possible that starting times will signif-
icantly increase at temperatures
below 32°F (0°C). At low temperatures
the use of a block heater is recommended
(see your authorized Mercedes-Benz
Center for further information). Rough
idling may also be experienced at such
temperatures before the engine is fully
warmed up.
Hot weather performance
At ambient temperatures above 95°F
(35°C) start times may increase and be
accompanied by a rough idle following the
start.Cruising range
E85 fuel contains less energy per gallon
than gasoline. To ensure that engine per-
formance with Ethanol fuel is similar to
that when using gasoline, the engine must
burn more Ethanol fuel. As a result, it is to
be expected that the fuel consumption will
increase when using E85 compared to gas-
oline operation.
Maintenance
Please inform your Mercedes-Benz Center
if you use or have used E85 fuel when your
vehicle is delivered for maintenance or
repairs.
!E85 fuel is unsuitable for use when am-
bient temperatures fall below 14°F
(-10°C).
iUse of E85 may reduce your driving
range.
Page 336 of 376

336 Technical dataFuels, coolants, lubricants etc.Coolants
The engine coolant is a mixture of water
and anticorrosion / antifreeze, which pro-
vides:
Corrosion protection
Freeze protection
Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -22°F (-30°C) and corro-
sion protection.
If the antifreeze mixture is effective
to -22°F (-30°C), the boiling point of the
coolant in the pressurized cooling system
is reached at approximately 266°F
(130°C).The coolant solution must be used
year-round to provide the necessary corro-
sion protection and increase boil-over pro-
tection. You should have it replaced every
15 years or 150 000 miles (250 000 km),
whichever comes first. Coolant system
design and coolant used stipulate the
replacement interval. The above replace-
ment interval is only applicable if
MB 325.0 anticorrosion/antifreeze
solution or other Mercedes-Benz approved
products of equal specification (see
Factory Approved Service Products pam-
phlet) are used to renew the coolant con-
centration or bring it back up to the proper
level.
To provide important corrosion protection,
the solution must be at least 45% anticor-
rosion/antifreeze [equivalent to freeze
protection to approx. -22°F (-30°C)]. If you use a solution that is more than 55%
anticorrosion/antifreeze [freeze protec-
tion to approx. -49°F (-45°C)], the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this
amount of anticorrosion/antifreeze.
If the coolant level is low, water and
MB 325.0 anticorrosion /antifreeze should
be used to bring it up to the proper level
(have cooling system checked for signs of
leakage). Please make sure that the mix-
ture is in accordance with label instruc-
tions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult your authorized Mercedes-Benz
Center.