2007 MERCEDES-BENZ CLK350 COUPE air conditioning

196 Controls in detail
Automatic climate control
The automatic climate control is operation-
al whenever the engine is running. You can
operate the automatic climate control sys-
tem in either the automatic or manual
mode. The system cools or heats the inte-
rior depending on the selected interior
temperature and the current outside tem-
perature.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 theA/C mode is deactivated
(
page 204).
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 195) 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 fea-
ture” (
page 248). The automatic climate con-
trol will then adjust the interior temperature to
the set value much faster.
Keep the air intake grille in front of the wind-
shield free of snow and debris.
Do not obstruct air flow by placing objects on the
air flow-through exhaust slots below the rear
window.

200 Controls in detail
Automatic climate control
Adjusting air volume
Use buttonU (
page 195) for auto-
matic mode or air volume controls

orQ (
page 195) to adjust air volume
manually.
Seven blower speeds are available.
Press button
to decrease
orQ (
page 195) to increase air
volume to the desired level.
The indicator lamp on the buttonU
goes out.
The automatic air distribution remains
switched on.
Front defroster
You can use this setting to defrost the
windshield, for example if it is iced up.
You can also defog the windshield and the
side windows.
Activating
Press buttonP or0
(
page 195).
The indicator lamp on the button
comes on.
The air conditioning switches
automatically to the following functions:

cooling on to dehumidify

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) 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 56).
If the automatic mode of the automatic cli-
mate control is switched off:
Turn air distribution control1 or8
toa orY (
page 195).
iKeep this setting selected only until the
windshield or the side windows are clear again.
iIf you have switched on the defrost function
using thePor0 button, you cannot
make any other settings.
iThe cooling remains switched on.
iKeep this setting selected only until the
windshield is clear again.

201 Controls in detail
Automatic climate control
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).
Air recirculation mode
Switch to air recirculation mode to prevent
unpleasant odors from entering the vehicle
from the outside (e.g. before driving
through a tunnel). This setting cuts off the
intake of outside air and recirculates the
air in the passenger compartment.Activating
Press button, (page 195).
The indicator lamp on the button
comes on.
Warning!G
Fogged windows impair visibility, endanger-
ing you and others. If the windows begin to
fog on the inside, switching off the air
recirculation mode immediately should clear
interior window fogging. If interior window
fogging persists, make sure the air
conditioning (
page 204) is activated, or
press buttonP or 0.
iThe air recirculation mode is activated auto-
matically at high outside temperatures.
The indicator lamp on button, is not lit when
the air recirculation mode is automatically
switched on.
A quantity of outside air is added after approxi-
mately 30 minutes.

202 Controls in detail
Automatic climate control
Deactivating
Press button, (page 195).
The indicator lamp on the button goes
out.Air recirculation mode with conve-
nience closing or opening featureConvenience closingPress and hold button,
(
page 195) until the windows and the
tilt/sliding sunroof* are closed or have
reached the desired position. The indi-
cator lamp on the button comes on.
The air recirculation mode is activated.
Convenience opening
Press and hold button,
(
page 195) until the windows and the
tilt/sliding sunroof* have return to
their previous position or they have
reached the desired position. The indi-
cator lamp on the button goes out. The
air recirculation mode is deactivated.
iThe air recirculation mode is deactivated au-
tomatically:

after 5 minutes if the outside temperature is
below approximately 41°F (5 °C)

after 5 minutes if the air conditioning is
turned off

after 30 minutes if the outside temperature
is above approximately 41°F (5 °C)
Warning!G
Never operate the side windows and the
tilt/sliding sunroof* if there is the possibility
of anyone being harmed by the closing
procedure.
When using the air recirculation mode with
convenience closing feature, should the up-
ward movement of a window be blocked by
some obstructions including but not limited
to arms, hands, fingers. etc., the automatic
reversal feature will not operate.
In the event that the procedure causes
potential danger, the closing of the side
windows can be immediately halted by
releasing the, button or by pressing or
pulling the respective window switch. The
closing of the tilt/sliding sunroof* can be
immediately halted by releasing the,
button or by moving the tilt/sliding sunroof*
switch in the overhead control panel in any
direction.
iA side window or tilt/sliding sunroof* will
only return to its previous position if it has not
been moved to another position using the re-
spective side window switch or tilt/sliding sun-
roof* switch after it was closed with
button,. A side window or tilt/sliding sun-
roof* that was moved will remain in its current
position if button, is used to re-open the re-
maining side windows or tilt/sliding sunroof*.

204 Controls in detail
Automatic climate control
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 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.
Press button2or9
(
page 195) 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 underneath
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 it-
self off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Center.

206 Controls in detail
Automatic climate control
Rear passenger compartment
adjustable air vents
The air conditioning for the rear passenger
compartment is controlled via the auto-
matic climate control panel (
page 195).The air vents for the rear passenger
compartment are located in the rear
center console.
1Thumbwheel for air volume control for
center air vents
2Left center air vent
3Right center air ventAdjusting air distribution
Push the slide for the left center
vent2 or right center vent3 to the
left, right, up or down.
The air flow is directed in the corre-
sponding direction.
Adjusting air volume
Turn thumbwheel1 to the left or right.
The air volume is increased or de-
creased.
iThe temperature at the center air vents2
and3 for the rear passenger compartment
(
page 206) is the same as at the dashboard
center air vents.iFor draft-free ventilation, move the slider for
the center air vents2 and3 upward.

337 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least 3 hours or driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross Vehicle Weight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.

440 Technical data
Layout of poly-V-belt drive
CLK 350/CLK 550
1Idler pulley
2Idler pulley
3Automatic belt tensioner
4Power steering pump
5Air conditioning compressor
6Crankshaft
7Coolant pump
8Generator (alternator)