Page 202 of 498
200 Controls in detailAutomatic climate control (CLK 500/CLK 55 AMG)Defrosting
Activating
Press buttonP or0
(page 195).
The indicator lamp on the button
comes on.
The air conditioning switches automatical-
ly to the following functions:
maximum blowing and heating
power
air flows onto the windshield and
the front side windows
the air recirculation mode is
switched offDeactivating
Press buttonP or0
(page 195).
The indicator lamp on the button goes
out. Defrosting is turned off.
The previous settings are once again in
effect.
Maximum cooling MAXCOOL
If the left and right air distribution controls
as well as the airflow volume control are
set toU (
page 195) and there is a
high need for cooling, the display
“MAXCOOL” appears.
This provides the fastest possible cooling
of the vehicle interior (when side windows
and tilt/sliding sunroof* are closed).
iThese settings should only be selected
for a short time.
Page 206 of 498
204 Controls in detailAutomatic climate control (CLK 500/CLK 55 AMG)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.
Automatic climate control panel
design A
Press button° (
page 195).
The indicator lamp on the button
comes on.
The cooling function switches off after
a short delay.
Automatic climate control panel
design B
Press button2(
page 195).
The indicator lamp on the button goes
out.
The cooling function switches off after
a short delay.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condi-
tioning.
Automatic climate control panel
design A
Press button°(
page 195) again.
The indicator lamp on the button goes
out.
The cooling function is switched on.
Automatic climate control panel
design B
Press button2(
page 195)
again.
The indicator lamp on the button
comes on.
The cooling function is switched on.
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.Warning!
G
If you turn off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog
up more quickly. Window fogging may
impair visibility and endanger you and
others.
Page 213 of 498
211 Controls in detail
Audio system
Switching off
Remove SmartKey from starter switch.
or
Press M button.
Adjusting the volume
Turn rotary control of N button.
The volume will increase or decrease
depending on the direction turned.Adjusting sound functions
The bass and treble functions are called up
by pressing the O button.
Settings for bass and treble are stored
separately for the AM and FM wavebands,
weather band, CD mode and telephone
mode.
Bass
Press O button repeatedly until BASS
appears in the display.
Press
+ or
– soft key to increase or de-
crease tone level accordingly.
or
Press
RES
soft key briefly to reset bass
tones to their center level.
The radio switches back to the stan-
dard radio menu eight seconds after
the last soft key is pressed.
iShould excessively high temperatures
occur while the audio system is being
operated, the display will dim. If tem-
peratures continue to rise,
HIGH TEMP
will appear in the display, after which
the audio system will be switched off
for a cooling-down period.
iIf your vehicle equipment includes a
Mercedes-Benz specified mobile
telephone*, you can adjust its volume
separately from the volume of the
audio system while the telephone is
being used.
Page 315 of 498
313 Operation
Engine compartment
Coolant
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
compartment.
1Coolant expansion tank
2Cap
Using a rag, turn cap 2 slowly
approximately one half turn to the left
to release any excess pressure.
Continue turning the cap 2 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 2.
More information on coolant can be found
in the “Technical data” section
(
page 452).
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 the coolant temperature is
above 158°F (70°C). Allow the coolant
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
1/2 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.
Page 359 of 498
357 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
Add coolant to prevent engine from
overheating (
page 313).
If this warning lamp comes on frequently,
there is a leak in the cooling system.
Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.
If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).
Stop as soon as possible and allow
the engine and coolant to cool down.
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 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.
Page 377 of 498
375 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
?
Visit workshop!
There may be a malfunction in the
fuel injection system
ignition system
exhaust system
fuel system
Have the measuring system checked
by an authorized Mercedes-Benz Cen-
ter.
B
Coolant
Check level
The coolant level is too low.
Add coolant (
page 313).
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 en-
gine damage.
Page 379 of 498
377 Practical hints
What to do if …?
Display symbol
Display message
Possible cause
Possible solution
•
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 in-
operative water pump which may re-
sult 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.
Drive immediately to the nearest au-
thorized Mercedes-Benz Center.
Coolant
Visit workshop!
The cooling fan for the coolant is malfunc-
tioning.
Observe the coolant temperature dis-
play.
Have the fan replaced as soon as pos-
sible.
Page 450 of 498
448 Technical dataFuels, coolants, lubricants, etc.
Model
Capacity
Fuels, coolants, lubricants, etc.
Cooling system
CLK 320
CLK 500
CLK 55 AMG
approx. 10.7 US qt (10.0 l)
approx. 12.8 US qt (12.0 l)
approx. 12.8 US qt (12.0 l)
MB 325.0 Anticorrosion/Antifreeze
Agent
Fuel tank
including a reserve of
CLK 320
CLK 500
CLK 55 AMG
16.35 US gal (62.0 l)
2.11 US gal (8.0 l)
2.11 US gal (8.0 l)
2.64 US gal (10.0 l)
Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg.of96RON/86MON)
Air conditioning system
R-134a refrigerant and special PAG lu-
bricant oil (never R-12)
Windshield washer and
headlamp cleaning system*
6.4 US qt (6.0 l)
MB Windshield Washer Concentrate
1
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 454).
