2004 MERCEDES-BENZ C320S coolant temperature

257 Operation
Engine compartment
Coolant 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 cap slowly approxi-
mately one half turn to the left to
release 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.
For more information on coolant, see
“Coolants” (
page 356).
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
approximately
1/2 turn to relieve excess
pressure. If opened immediately, scald-
ing hot fluid and steam will be blown out
under pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene
glycol which may burn if it comes into
contact with hot engine parts.

288 Practical hintsWhat 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 symbol
Display message
Possible cause
Possible 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 over-
heated 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 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 the
engine has cooled 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.

289 Practical hints
What 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
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.

290 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
Ñ
CRUISE CONTROL
DRIVE TO WORKSHOP!
Cruise control is malfunctioning.

Visit an authorized Mercedes-Benz
Center.
G
VISIT WORKSHOP!
DISPLAY MALFUNCTION
The instrument cluster display is
malfunctioning.

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Center as soon as possible.
The displays for several systems have
malfunctioned. Some systems them-
selves may also have malfunctioned.

Have the electronic systems checked
by an authorized Mercedes-Benz
Center.
±
VISIT WORKSHOP!
DISPLAY MALFUNCTION
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 276).
J
DOOR OPEN!
You are attempting to drive with one or
more doors open.

Close the doors.

350 Technical dataFuels, coolants, lubricants, etc.
Model
Capacity
Fuels, coolants, lubricants, etc.
Front axle
C2404MATIC
C3204MATIC
0.5 US qt (0.46 l)
Hypoid gear oil SAE 85 W 90
Transfer case
C2404MATIC
C3204MATIC
approx. 0.62 US qt (0.59 l)
MB Transfer case fluid
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
C 240 (all models)
C 320 (all models)
C32AMG
approx. 5.9 US qt (5.6 l)
approx. 6.8 US qt (6.4 l)
approx. 6.8 US qt (6.4 l)
approx. 6.8 US qt (6.4 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 (identified by a label
reading Premium gasoline or E85 only! on
fuel filler flap):
Alternative fuel: Ethanol fuel (E85)

351 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
3.2 US qt (3.0 l)
MB Windshield Washer Concentrate
1
Windshield washer and
headlamp cleaning system*
6.4 US qt (6.0 l)
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 358).

355 Technical data
Fuels, coolants, lubricants, etc.
When switching fuels, make sure:

Fuel level is below half full.


Fuel level is above reserve (fuel 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 (Canada only) 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
gasoline 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
ambient temperatures fall below 14°F
(-10°C).
iUse of E85 may reduce your driving
range.

356 Technical dataFuels, coolants, lubricants, etc.Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which
provides:

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
corrosion 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 approx. 266°F (130°C).The coolant solution must be used
year-round to provide the necessary corro-
sion protection and increase boil-over
protection. Refer to Service Booklet for
replacement interval.
Coolant system design and coolant used
stipulate the replacement interval. The
replacement interval published in the
Service Booklet is only applicable
if MB 325.0 anticorrosion/antifreeze
solution or other Mercedes-Benz approved
products of equal specification (see
Factory Approved Service Products
pamphlet) are used to renew the coolant
concentration or bring it back up to the
proper level.
To provide important corrosion protection,
the solution must be at least 45%
anticorrosion/antifreeze [equivalent to
freeze protection to approx. -22°F
(-30°C)]. If you use a solution that is more than 55%
anticorrosion/antifreeze [freeze
protection 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 the mixture is
in accordance with label instructions.
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,
consult your authorized Mercedes-Benz
Center.