Page 232 of 370

238 OperationEngine compartmentCoolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
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 334).
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 ½ 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.
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Page 259 of 370
265 Practical hints
What to do if …
Display
Possible cause
Suggested solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.
Add coolant (
page 238).
If you have to add coolant frequent-
ly, have the cooling system
checked by an authorized
Mercedes-Benz 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 can 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 major en-
gine damage.
S203 MY03_A.book Page 265 Tuesday, January 28, 2003 2:22 PM
Page 260 of 370

266 Practical hintsWhat to do if …
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 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
otherwise 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.
S203 MY03_A.book Page 266 Tuesday, January 28, 2003 2:22 PM
Page 261 of 370
267 Practical hints
What 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. No-
tify 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 mal-
functioning.
Observe the coolant temperature
display.
Have the fan replaced as soon as
possible.
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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 ser-
vice station.
G
VISIT WORKSHOP!
DISPLAY DEFECTIVE
The instrument cluster display is mal-
functioning.
Continue driving with added cau-
tion.
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 258).
W
WASHER FLUID
CHECK LEVEL!
The fluid level has dropped to about
1/3
of total reservoir capacity.
Add washer fluid (
page 240).
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Page 311 of 370
317 Technical data
Spare parts service
Warranty coverage
Identification labels
Layout of poly-V-belt drive
Engine
Rims and Tires
Electrical system
Main Dimensions
Weights
Fuels, coolants, lubricants etc.
Consumer information
S203 MY03_A.book Page 317 Tuesday, January 28, 2003 2:22 PM
Page 322 of 370

328 Technical dataFuels, coolants, lubricants etc.
Fuels, coolants, lubricants etc.Capacities
Vehicle components and their respective lubricants must match. Therefore use only
brands tested and recommended by us.
Please refer to the Factory Approved Service Products pamphlet, or inquire at
your Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants etc.
Engine with oil filter
C 240
C 320
C 240 4MATIC
C 320 4MATIC
7.9 US qt (7.5 l)
7.9 US qt (7.5 l)
7.4 US qt (7.0 l)
7.4 US qt (7.0 l)
Recommended engine oils
Automatic transmission
8.5 US qt (8.0 l)
MB Automatic Transmission Oil
1
1MB part no. 001 989 21 03 10Manual transmission
1.3 US qt (1.2 l)
MB Manual Transmission Oil
2
2MB part no. 001 989 26 03 10Rear axle
1.2 US qt (1.1 l)
Hypoid gear oil SAE 85 W 90
Front axle
C 240 4MATIC
C 320 4MATIC
0.5 US qt (0.46 l)
Hypoid gear oil SAE 85 W 90
Transfer case
C 240 4MATIC
C 320 4MATIC
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. 2.1 oz (60 g) each
High temperature roller bearing grease
Brake system
0.5 US qt (0.5 l)
MB Brake Fluid (DOT 4+)
Cooling system
approx. 6.8 US qt (6.4 l)
MB 325.0 Anticorrosion/Antifreeze Agent
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330 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 recom-
mended brands is available in the Factory
Approved Service Products pamphlet, or at
your authorized Mercedes-Benz Center.
Please follow FSS recommendations for
scheduled oil changes. Failure to do so
could result in engine damage not covered
by the Mercedes-Benz Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil.
They may be harmful to the engine opera-
tion.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil is used in the air conditio-
ning system.
Never use R-12 (CFC) or mineral-based lu-
bricating oil, otherwise damage to the
system will occur.
Brake fluid
During vehicle operation, the boiling point
of the brake fluid is continuously reduced
through the absorption of moisture from
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be re-
placed every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your au-
thorized Mercedes-Benz Center will pro-
vide you with additional information.
S203 MY03_A.book Page 330 Tuesday, January 28, 2003 2:22 PM