cooling MERCEDES-BENZ C240 2001 W203 Owner's Manual

141 Climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Climate control
The system is always at operational readiness, except
when manually switched off.
The climate control only operates with the engine
running.
The temperature selector should be left at the desired
temperature setting. The temperature selected is
reached as quickly as possible.
The system will not heat or cool any quicker by setting a
higher or lower temperature.
The desired interior temperature can be selected
separately for the left and right side of the passenger
compartment.
The climate control removes considerable moisture from
the air during operation in the cooling mode. It is
normal for water to drip on the ground through ducts in
the underbody.
The air conditioning will not engage (no cooling) if the
economy mode S is selected, see page 145. Notes:
Do not obstruct the air flow by placing objects on the air
flow-through exhaust slots below the rear window.
Also keep the air intake grill in front of the windshield
free of snow and debris.
The storage compartment between the front seats can be
ventilated. See page 158 for notes on ventilating the
storage space under the armrest in the center console.
The air conditioner switches itself off for its own
protection if refrigerant is lost. No cooling will then take
pl ac e. Ec on omy mod e S cann ot be switched of f . Have
the air conditioner checked by a Mercedes-Benz Center
should this happen.
Dust filter
Nearly all dust particles and pollen are filtered out
before outside air enters the passenger compartment
through the air distribution system.

149 Automatic climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index 1Temperature, left
2Temperature, right
3Air volume
4Automatic mode is selectedAutomatic climate control
The system is always at operational readiness, except
when manually switched off.
The automatic climate control only operates with the
engine running.
The temperature selector should be left at the desired
temperature setting. The temperature selected is
reached as quickly as possible.
The system will not heat or cool any quicker by setting a
higher or lower temperature.
The desired interior temperature and air distribution
can be selected separately for the left and right side of
the passenger compartment.
The automatic climate control removes considerable
moisture from the air during operation in the cooling
mode. It is normal for water to drip on the ground
through ducts in the underbody.
The air conditioning will not engage (no cooling) if the
economy mode S is selected, see page 155.

150 Automatic climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Notes:
Do not obstruct the air f low by placing objects on the air
flow-through exhaust slots below the rear window.
Also keep the air intake grill in front of the windshield
free of snow and debris.
The storage compartment between the front seats can be
ventilated. See page 158 for notes on ventilating the
storage space under the armrest in the center console.
The air conditioner switches itself off for its own
protection if refrigerant is lost. No cooling will then take
place. Economy mode S can n ot be s witched of f. Have
the air conditioner checked by a Mercedes-Benz Center
should this happen.
Dust filter
Nearly all dust particles and pollen are filtered out
before outside air enters the passenger compartment
through the air distribution system.Basic setting – automatic mode
Briefly press left or right U button. The h, j
and k symbols will no longer be visible.
The economy mode and air recirculation functions will
be switched off. The automatic blower will be activated
at the same time.
Set the temperature switches on the left and right
to 72
°F (22
°C). This provides for comfortable conditions
in the vehicle.
Heating mode:
To lower headroom temperature, use thumbwheel
(4, page 146).
Air conditioning mode:
Open air outlets at dashboard top center (7, page 146)
for an even air distribution.

281 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index COOLANT (coolant level)
* C = Category, see page 274When this message appears while driving, the coolant
level has dropped below the required level. If no leaks
are noticeable and the engine temperature does not
increase, continue to drive to the nearest service station
and have coolant added to the coolant system.The low engine coolant level warning should not be
ignored. Extended driving with the symbol displayed
may cause serious engine damage not covered by the
Mercedes-Benz Limited Warranty.
In cases of major or frequent minor coolant loss, have
the cooling system checked at your authorized
Mercedes-Benz Center as soon as possible.
Note:
Do not drive without coolant in the cooling system. The
engine will overheat causing major engine damage.
Monitor the coolant temperature gauge while driving,
see page 124.
See page 302 for instructions on topping up the coolant.Line 1 Line 2 C*
COOLANT CHECK LEVEL! 2
Wa r n i n 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.

282 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
COOLANT (coolant temperature)
* C = Category, see page 274
1 This may indicate that the poly-V-belt has broken. Should this
con dition o ccur, the poly-V-belt must be repla ced befo re co ntin uin g
to operate the vehicle. Otherwise, the engine will overheat due to
an inoperative water pump which may result in damage to the
engine. 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.
2 The cooling fan for the coolant is faulty. Observe the coolant
temperature gauge. See page 124
During severe operating conditions and stop-and-go city
traffic, the coolant temperature may rise close to 120
°C.
The engine should not be operated with the coolant
temperature above 120
°C. Doing so may cause serious
engine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Line 1 Line 2 C*
COOLANT STOP, ENGINE OFF!
1
1
COOLANT VISIT WORKSHOP!
2
2
Wa r n i n g !
Driving when your engine is badly overheated 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.

302 Engine compartment
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Adding coolant
If coolant has to be added, a 50/50 mixture of water and
MB anticorrosion / antifreeze should be added.Windshield and headlamp washer system
1Windshield and headlamp washer fluid reservoir
The reservoir should be refilled with MB Windshield
Washer Concentrate and water (or concentrate
commercially available premixed windshield washer
solvent / antifreeze, depending on ambient
temperatures).
Wa r n i n g !
• In order to avoid 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 indicates 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 cap approximately
1/2 turn to relieve excess pressure. If opened
immediately, scalding 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.

355 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index 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.
Capacity Fuels, coolants, lubricants etc.
Engine with oil filter 8.5 US qt (8.0 l) Recommended engine oils
Automatic transmission 8.5 US qt (8.0 l) Automatic transmission fluid
Rear axle 1.2 US qt (1.1 l) Hypoid gear oil SAE 85 W 90
Power steering approx. 1.1 US qt (1.0 l) MB Power steering fluid
Front wheel hubs approx. 2.1 oz (60 g) each High temperature roller bearing grease
Accelerator control linkage Hydraulic fluid
Brake system approx. 0.5 US qt (0.5 l) MB Brake fluid (DOT 4+)
Cooling system approx. 9.5 US qt (10.5 l) MB Anticorrosion / antifreeze
Fuel tank
including a reserve of16.4 US gal (62.0 l)
2.1 US gal (8.0 l)Premium unleaded gasoline: Posted Octane 91
(Avg. of 96 RON / 86 MON)

359 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Gasoline additives
A major concern among engine manufacturers is carbon
build up caused by gasoline. Mercedes-Benz
recommends the use of only quality gasoline containing
additives that prevent the build up of carbon deposits.
After an extended period of using fuels without such
ad ditives , car bon d ep osits c an bui ld up esp eci ally on t he
intake valves and in the combustion area, leading to
engine performance problems such as:
•warm-up hesitation,
•unstable idle,
•knocking / pinging,
•misfire,
•power loss.
Do not blend other specific fuel additives with fuel.
They only result in unnecessary cost, and may be
harmful to the engine operation.
Damage or malfunctions resulting from poor fuel
quality or from blending specific fuel additives are not
covered by the Mercedes-Benz Limited Warranty.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 approximately 266
°F
(130
°C).
The coolant solution must be used year round to provide
the necessary corrosion protection and increase in the
boil-over protection. You should have it replaced every
3years.
To provide the important corrosion protection, the
solution must be at least 45% anticorrosion / antifreeze
(equals a freeze protection to approximately - 22
°F
(- 30
°C). If you use a solution that is more than 55%
anticorrosion /antifreeze (freeze protection to
approximately - 49
°F (- 45
°C), the engine temperature

360 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
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 anticorrosion /
antifreeze should be used to bring it up to the proper
level (have cooling system checked for signs of leakage).
The water in the cooling system must meet minimum
requirements, which are usually satisfied by normal
drinking water. If your are not sure about the water
quality, consult your authorized Mercedes-Benz Center.
Anticorrosion / antifreeze
Your vehic le con tain s a n umbe r o f alumi nium parts. The
use of aluminium components in motor vehicle engines
necessitates that anticorrosion / antifreeze coolant used
in such engines be specifically formulated to protect the
aluminium parts. (Failure to use such anticorrosion /
antifreeze coolant will result in a significantly
shortened service life.)
Therefore the following product is strongly
recommended for use in your vehicle: Mercedes-Benz
anticorrosion / antifreeze agent.Before the start of the winter season (or once a year in
the hot southern regions), you should have the
anticorrosion / antifreeze concentration checked. The
coolant is also regularly checked each time you bring
your vehicle to your authorized Mercedes-Benz Center
for service.
Anticorrosion / antifreeze quantity
Approximately freeze protection
– 35
°F
(– 37°C)– 49
°F
(– 45°C)
4.8 US qt
(4.5 l)5.3 US qt
(5.0 l)