
121 Automatic climate control
Technical
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index 1Air volume control for center air outlets, turn wheel 
up to open.
2Air volume control for side air outlet.
To open air outlets: Turn wheel to position i.
3Center air outlet, adjustable
4Side air outlet, adjustable
5Display and controls
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 q uicker by setting a 
higher or lower temperature.
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 desired interior temperature can be selected 
separately for the left and right side of the passenger 
compartment.
Note:
If the individual settings (page 106) of the outside 
temperature display is switched from °C to 
°F or vice 
versa, the automatic climate control returns to the 
factory settings. Set temperature and activate S 
mode.
J_A208.book Seite 121 Donnerstag, 31. Mai 2001 9:35 09 

125 Automatic climate control
Technical
data Instruments 
and controlsOperationDrivingInstrument 
cluster displayPractical hints Car care Index Air recirculation
This mode can be selected to temporarily reduce the 
entry of annoying odors or dust into the vehicle’s 
interior.
Outside air is not supplied to the vehicle’s interior.
To select, press O button.
To c a nc el,  pr ess  O button again.
The system will automatically switch from recirculated 
air to fresh air
•after approx. 5 minutes at outside temperatures 
below approx. 40
°F (5
°C),
•after approx. 30 minutes at outside temperatures 
above approx. 40
°F (5
°C),
•after approx. 5 minutes, if button S is pressed.
If the windows should fog up from the inside, switch 
from recirculated air back to fresh air.
At high outside temperatures, the system automatically 
engages the recirculated air mode thereby increasing 
the cooling capacity performance, switching to partially 
fresh air within 30 minutes.Residual engine heat utilization
With the engine switched off, it is possible to continue 
heating the interior for a short while.
Air volume and distribution are controlled 
automatically.
To   s e l e c t :
Turn electronic key in steering lock to position 1 or 0 or 
remove key.
Press T button
This function selection will not activate if the battery 
charge level is insufficient.
To   c a n c e l :
Press T button.
The system will automatically shut off
•if you turn electronic key in steering lock to 
position 2,
•after approx. 30 minutes,
•if the battery voltage drops.
J_A208.book Seite 125 Donnerstag, 31. Mai 2001 9:35 09 

239 Malfunction and warning messages
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hints Car care Index PA R K I N G   B R A K E
Parking brake, see page 204.ENGINE FAN
1 The cooling fan for the coolant is faulty. Observe coolant 
temperature gauge while driving, see page 86. Line 1 Line 2
PARKING BRAKE RELEASE BRAKE!Line 1 Line 2
ENGINE FAN VISIT WORKSHOP!
1
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240 Malfunction and warning messages
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hints Car care Index
COOLANT (coolant level)
When 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.
Notes:
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 257 for instructions on adding coolant.
Line 1 Line 2
COOLANT CHECK LEVEL!
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.
J_A208.book Seite 240 Donnerstag, 31. Mai 2001 9:35 09 

258 Engine compartment
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hintsCar care Index
Adding coolant
If c oolan t has  to b e ad de d,  a 50 / 5 0  m ixture of water and  
MB anticorrosion / antifreeze should be added.
The drain plugs for the cooling system are located on 
the right side of the engine block and at the bottom of 
the radiator.
Anticorrosion / antifreeze mixture, see page 323.
Wa r n i n g !
In order to avoid possible serious burns or injury:
• 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.
J_A208.book Seite 258 Donnerstag, 31. Mai 2001 9:35 09 

318 Fuels, coolants, lubricants etc. - capacities
Technical
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.
Fuels, coolants, lubricants etc. Model Capacity
Engine with oil filter
(recommended engine oils)CLK 320, CLK 430
CLK 55 AMG8.5 US qt (8.0 l)
8.0 US qt (7.5 l)
Automatic transmission
(automatic transmission fluid)CLK 320
CLK 430, CLK 55 AMG8.5 US qt (8.0 l)
9.6 US qt (9.1 l)
Rear axle
(Hypoid gear oil SAE 90, 85 W 90)1.4 US qt (1.3 l)
Power steering
(MB Power steering fluid)approx. 1.1 US qt (1.0 l)
Front wheel hubs
(high temperature roller bearing grease)approx. 2.1 oz (60 g) each
Brake system
(MB Brake fluid (DOT 4))approx. 0.5 US qt (0.5 l)
Cooling system
(MB Anticorrosion/antifreeze)CLK 320
CLK 430, CLK 55 AMGapprox. 9.5 US qt (9.0 l)
approx. 11.7 US qt (11.1 l)
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322 Fuels, coolants, lubricants etc.
Technical
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 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]), 
J_A208.book Seite 322 Donnerstag, 31. Mai 2001 9:35 09 

323 Fuels, coolants, lubricants etc.
Technical
data Instruments 
and controlsOperation DrivingInstrument 
cluster displayPractical hints Car care Index the engine temperature will increase due to the lower 
heat tran sfer  c ap ability of the s olution . There for e, d o n ot 
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 vehicle contains a number of aluminum parts. The 
use of aluminum components in motor vehicle engines 
necessitates that anticorrosion/antifreeze coolant used 
in such engines be specifically formulated to protect the 
aluminum 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
Model Approx. freeze protection
-35
°F 
(-37°C)-49
°F (
-45°C)
CLK 320 4.8 US qt 
(4.5 l)5.3 US qt 
(5.0 l)
CLK 430, 
CLK 55 AMG5.9 US qt 
(5.6 l)6.5 US qt 
(6.1 l)
J_A208.book Seite 323 Donnerstag, 31. Mai 2001 9:35 09