2006 MERCEDES-BENZ CLK500 cooling

198 Controls in detailAutomatic climate control (CLK 500/CLK 55 AMG)The automatic climate control is operation-
al whenever the engine is running. You can
operate the climate control system in ei-
ther the automatic or manual mode. The
system cools or heats the interior depend-
ing on the selected interior temperature
and the current outside temperature.Nearly all dust particles, pollutants and
odors are filtered out before outside air
enters the passenger compartment
through the air distribution system.
The air conditioning will not engage (no
cooling) if the A/C mode is deactivated
(
page 206).
Warning!
G
When operating the automatic climate
control, the air that enters the passenger
compartment through the air vents can be
very hot or very cold (depending on the set
temperature). This may cause burns or frost-
bite on unprotected skin in the immediate
area of the air vents. Always keep sufficient
distance between unprotected parts of the
body and the air vents. If necessary, use the
air distribution controls (
page 197) to
direct the air to air vents in the vehicle inte-
rior that are not in the immediate area of un-
protected skin.
Warning!
G
Follow the recommended settings for
heating and cooling given on the following
pages. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
iSevere conditions (e.g. strong air
pollution) may require replacement of
the filter before its scheduled interval.
A clogged filter will reduce the air
volume to the interior.
If the vehicle interior is hot, ventilate
the interior before driving off, see
“Summer opening feature”
(page 252). The automatic climate
control will then adjust the interior
temperature to the set value much
faster.
Keep the air intake grille in front of the
windshield free of snow and debris.
Do not obstruct air flow by placing
objects on the air flow-through exhaust
slots below the rear window.

199 Controls in detail
Automatic climate control (CLK 500/CLK 55 AMG)
Deactivating the automatic climate control system
Deactivating
Press button´ (
page 197).
The indicator lamp on the button´
comes on.
Reactivating

Press button´ (
page 197).
The indicator lamp on the button´
goes out.Operating the climate control system
in automatic mode
Activating
Press buttonU (
page 197) while
the engine is running.
The indicator lamp on the button
comes on. The air volume and air distri-
bution are adjusted automatically.1Temperature, left
2Blower speed
3Temperature, right

Use temperature controls3 and
dor6 and b (
page 197) to sepa-
rately adjust the air temperature on
each side of the passenger compart-
ment.
The temperature of the vehicle interior
is adjusted automatically.
Deactivating

Press buttonU (
page 197) again.
The indicator lamp on the button goes
out. The automatic operation of air vol-
ume and air distribution switches off.
iWhen the air conditioning is switched
off, the outside air supply and circula-
tion are also switched off. Only choose
this setting for a short time. Otherwise
the windows could fog up.
iWhen operating the climate control
system in automatic mode, you will
only rarely need to adjust the tempera-
ture, air volume and air distribution.
In automatic mode, cooling with dehu-
midify is switched on. This function can
be switched off if necessary.iYou can switch the automatic climate
control system on and off for each side
of the passenger compartment as de-
sired.

202 Controls in detailAutomatic climate control (CLK 500/CLK 55 AMG)The air conditioning switches
automatically to the following functions:


cooling on the dehumidify


maximum blowing and heating
power


air flows onto the windshield and
the front side windows


the air recirculation mode is
switched off
Deactivating

Press buttonP or0
(page 197) again.
The indicator lamp on the button goes
out.
The previous settings are once again in
effect.Windshield fogged on the outside

Switch the windshield wipers on
(page 54).
If the automatic mode of the automatic cli-
mate control is switched off:

Turn air distribution control1 or8
toa orY (
page 197).
Maximum cooling MAXCOOL
If the left and right air distribution controls
as well as the airflow volume control are
set toU (
page 197) 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 soft top are closed).
iThe cooling remains switched on.
iKeep this setting selected only until the
windshield is clear again.

206 Controls in detailAutomatic climate control (CLK 500/CLK 55 AMG)Air conditioning
The cooling function, only operational
when the engine is running, cools the vehi-
cle interior down to the selected tempera-
ture. The cooling function also
dehumidifies the air in the vehicle interior,
thus preventing the windows from fogging
up.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 button2or9
(page 197).
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.

Press button2or9
(page 197) again.
The indicator lamp on the button
comes 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.
!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.

212 Controls in detailAudio systemButton and soft key operation
In these instructions, the alphanumeric
keypad (right side of radio panel) and the
function buttons (left side of radio panel)
are referred to as “buttons”. The four keys
below the display panel are referred to as
“soft keys”.
Operation
Switching the unit on/off
Switching on
Turn the SmartKey in the starter switch
to position 1 or 2.

If the audio system was on as you
removed the SmartKey from the starter
switch, the audio system will
automatically come back on as you
turn the SmartKey to position 1 or 2.
or

Press M button.Switching off

Remove SmartKey from starter switch.
or

Press M button.
!Do not press directly in the display
face. Otherwise, the display will be
damaged.
iIf the radio is switched on without the
key in the starter switch, it will
automatically switch off again after
approx. 30 minutes.
If your vehicle is equipped with a
telephone, the display may prompt you
to enter your PIN (GSM network) or
code (TDMA or CDMA network).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.

327 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 cap2 slowly
approximately one half turn to the left
to release any excess pressure.

Continue turning the cap2 to the left
and remove it.
The coolant level is correct if the level


for cold coolant: reaches the marking
(plastic bridge) inside the reservoir


for warm coolant: is approx. 0.6 in
(1.5 cm) higher

Add coolant as required.

Replace and tighten cap2.
More information on coolant can be found
in the “Technical data” section
(
page 484).
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.

377 Practical hints
What to do if …?
Problem
Possible cause/consequence
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 327).
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.

397 Practical hints
What to do if …?
Display symbol
Display message
Possible cause/consequence
Possible solution
ú
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 327).

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.