2004 MERCEDES-BENZ C320S cooling

170 Controls in detailAutomatic climate control*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 automatic
climate control system. The air in the
vehicle will then no longer be cooled or
dehumidified.
Press button° (
page 163).
The indicator lamp on the button
comes on.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condi-
tioning.

Press button° (
page 163).
The indicator lamp on the button goes
out.
The air conditioning 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 air conditioning cannot be turned
on again, this indicates that the air
conditioning is losing refrigerant. The
compressor has turned itself off.
Have the air conditioning checked at
the nearest authorized Mercedes-Benz
Center.

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.

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

Add coolant (
page 257).

If you have to add coolant frequently,
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
engine damage.

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.

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)

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.

367 Index
A
ABS 23, 72, 361
ABS control 72
Malfunction indicator lamp 274
Messages in display 284
Accelerator position,
automatic transmission* 147
Accident
In case of 49
Activating
Air conditioning (cooling)
Automatic climate control* 170
Climate control 160
Air recirculation mode
Automatic climate control* 167
Climate control 158
Anti-theft alarm system* 78
Automatic climate control* 163
Central locking (control system) 133
Charcoal filter 169
Climate control 155Climate control system 159
Defrosting
Automatic climate control* 167
Climate control 158
Easy-entry/exit feature* 134
ESP 76
Exterior headlamps 46
Exterior lamps 103
Exterior rear view mirror
parking position* 150
Hazard warning flasher 106
Headlamps 46
High beams 106
Ignition 31
Immobilizer 52
Rapid seat heating* 98
Rear fog lamp 104, 105
Rear window defroster 153
Residual heat 171
Seat heating* 98
Tow-away alarm* 80
Windshield wipers 48Adding
Coolant 257
Engine oil 255
Additional turn signals 310
Adjustable air vents,
rear passenger compartment
Automatic climate control* 172
Climate control 161
Adjusting 32
Air distribution
Automatic climate control* 166
Climate control 157
Air volume
Automatic climate control* 166
Climate control 157
Backrest contour 97
Backrest side bolsters 97
Backrest tilt
Manual seat 33
Power seat* 35
Exterior rear view mirrors 38

368 Index
Head restraint height, front seats
Manual seat 34
Power seat* 35
Head restraint height, rear seats 94
Head restraint tilt, front seats
Manual seat 34
Power seat* 36
Head restraint tilt, rear seats 96
Head restraints, rear seats
Folding back 95
Folding back with release
switch 95
Placing upright 95
Instrument cluster illumination 109
Interior rear view mirror 38
Manual seat 33
Mirrors 38
Multicontour seat* 97
Power seat* 35
Rear seat head restraints 94Seat belt height 42
Seat cushion depth 97
Seat cushion tilt
Manual seat 33
Power seat* 35
Seat fore and aft adjustment
Manual seat 33
Power seat* 35
Seat height
Manual seat 33
Power seat* 35
Seats 32
Steering column height,
electrical* 38
Steering column height,
manual 37
Steering column length,
electrical* 38
Steering column length,
manual 37
Steering wheel 36Air conditioning (cooling)
Turning off
Automatic climate control* 170
Climate control 160
Turning on
Automatic climate control* 170
Climate control 160
Air conditioning refrigerant 352
Air distribution
Adjusting
Automatic climate control* 166
Climate control 157
Air pressure see Tire inflation pressure
Air recirculation mode
Activating
Automatic climate control* 167
Climate control 158
Deactivating
Automatic climate control* 168
Climate control 159