2003 MERCEDES-BENZ C320 r button

154 Controls in detailClimate controlAir 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 climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.
Press buttonAC
OFF
(page 149).
The indicator lamp on the
buttonAC
OFF
lights up.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.

PressAC
OFF
again (
page 149).
The indicator lamp on the
buttonAC
OFF
goes out.
The air conditioning uses the
refrigerant R134a. This refrigerant is free
of CFC’s 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.
!If the air conditioning cannot be turned
on again, this indicates that the air con-
ditioning is losing refrigerant. The com-
pressor has turned itself off.
Have the air conditioning checked at
the nearest authorized Mercedes-Benz
Center.

159 Controls in detail
Automatic climate control*
Adjusting air distribution
Use air distribution controls2 and5
(page 157) to separately adjust the air
distribution on each side of the passenger
compartment. The following symbols are
found on the controls:
Adjusting manually

Press left or right
U
button.
The indicator lamp on the button goes
out.
The air distribution can be adjusted
manually.Adjusting automatically

Press left or right
U
button.
The indicator lamp on the button
comes on.
The air distribution is adjusted
automatically.
Windshield fogged on the outside

Switch the windshield wipers on.

Switch to manual mode.

Turn the air distribution control
to
a
or
Y
.
Adjusting air volume
Adjusting manually
Seven blower speeds are available.
Press left
M
or right
Q
side of air
volume control switch until the re-
quested blower speed is attained.
The display “Auto” disappears and the
automatic mode is switched off. The
selected blower speed is shown in the
display.
Adjusting automatically

Press left or right
U
button.
The indicator lamp on the button
comes on.
The air volume is adjusted
automatically.
Symbol
Function
a
Directs air through the center,
side and rear passenger
compartment air vents
Z
Directs air to the windows
X
Directs air into the entire
vehicle interior
Y
Directs air to the footwells

160 Controls in detailAutomatic climate control*Maximum cooling MAXCOOL
If the left and right air distribution controls
as well as the airflow volume control are
set to
U
and there is a high need for
cooling, the display “AUTO MAXCOOL” ap-
pears.
This provides the fastest possible cooling
of the vehicle interior (when windows and
sliding/pop-up roof* are closed).
Defrosting
Activating
Press button
P
.
The indicator lamp on the button lights
up.

Switch off air recirculation, if selected.

Press button
O
.
The indicator lamp on the button goes
out.

Close center air vents.

Adjust side air vents upwards.
Deactivating

Press button
P
.
The indicator lamp on the button goes
out. Defrosting is turned off.
Air recirculation mode
Switch to air recirculation mode to prevent
unpleasant odors from entering the vehicle
from the outside. This setting cuts off the
intake of outside air and recirculates the
air in the passenger compartment.
Activating
Press button
O
.
The indicator lamp on the button lights
up.
iThese settings should only be selected
for a short time.
Warning!
G
When the outside temperature is
below 41°F (5°C), only switch to air
recirculation mode for short periods to
prevent window fogging.

161 Controls in detail
Automatic climate control*
Deactivating
Press button
O
.
The indicator lamp on the button goes
out.
The air recirculation mode is deactivated
automatically:


after five minutes if the outside temper-
ature is below approximately 41°F
(5°C)


after five minutes if the air conditioning
is turned off


after 30 minutes if the outside temper-
ature is above approximately 41°F
(5°C)At outside temperatures above 79°F
(26°C) the system will not automatically
switch back to outside air. A quantity of
outside air is added after approximately
30 minutes.
Charcoal filter
An activated charcoal filter markedly re-
duces bad odors and removes pollutants
from air entering the passenger compart-
ment.
Activating
Press button
e
.
The indicator lamp on the button lights
up.
The system switches automatically to the
air recirculation mode if the carbon
monoxide (CO) or nitrogen oxide (NO
X)
concentration of the outside air increases
beyond a predetermined level.
iIf you keep button
O
pressed, the
side windows and the sliding/pop-up
roof* will be closed.
The air recirculation mode is activated
automatically:


at high outside temperatures


if the concentration of carbon mon-
oxide and nitrogen oxide in the out-
side air increases, for example in a
tunnel
Please note that the charcoal filter
must be activated (see below) for
the air recirculation mode to be
activated automatically.
If you have turned off the air condition-
ing (page 163) or the outside
temperature is below 41°F (5°C), the
air recirculation mode will not switch
on automatically.
iIf you keep button
O
pressed the
side windows and the sliding/pop-up
roof* will be returned to their previous
position.

162 Controls in detailAutomatic climate control*Deactivating
Press button
e
.
The indicator lamp on the button goes
out.
The automatic air recirculation mode does
not function if theACOFF
mode is selected
or if the outside temperature has fallen
below 41°F (5°C).The activated charcoal filter should be
switched off when windows fog up on the
inside, or if the passenger compartment
needs to be quickly heated or cooled
down.
Rear window defroster
The rear window defroster uses a large
amount of power. To keep the battery
drain to a minimum, switch off the defrost-
er as soon as the rear window is clear. The
defroster is automatically deactivated af-
ter approximately 6 to 17 minutes of oper-
ation depending on the outside
temperature.
Activating
Press button
F
.
The indicator lamp on the button lights
up.Deactivating

Press button
F
again.
The indicator lamp on the button goes
out.
iIf you keep button
e
pressed, the
side windows and the sliding/pop-up
roof* will be closed.
iIf you keep button
e
pressed, the
side windows and the sliding/pop-up
roof* will be returned to their previous
position.
Warning!
G
Any accumulation of snow and ice should be
removed from the rear window before driv-
ing. Visibility could otherwise be impaired,
endangering you and others.!If the rear window defroster switches
off too soon and the indicator lamp
starts blinking, this means that too
many electrical consumers are operat-
ing simultaneously and there is insuffi-
cient voltage in the battery. The system
responds automatically by deactivating
the rear window defroster.
As soon as the battery has sufficient
voltage, the rear window defroster au-
tomatically turns itself back on.

163 Controls in detail
Automatic climate control*
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 vehi-
cle will then no longer be cooled or dehu-
midified.
Press buttonAC
OFF
.
The indicator lamp on the
buttonAC
OFF
lights up.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.

PressAC
OFF
again.
The indicator lamp on the
buttonACOFF
goes out.
The air conditioning uses the
refrigerant R134a. This refrigerant is free
of CFCs which are harmful to the ozone
layer.
Residual heat and ventilation*
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
Activating
Turn the key in the starter switch to
position1 o r r e m o v e i t f r o m t h e s t a r t e r
switch.

Press button
T
.
The indicator lamp on button
T

comes on.
Deactivating

Press button
T
.
The indicator lamp on button
T

goes off.
iCondensation may drip out from under-
neath the vehicle. This is normal and
not an indication of a malfunction.
!If the air conditioning cannot be turned
on again, this indicates that the air con-
ditioning is losing refrigerant. The com-
pressor has turned itself off.
Have the air conditioning checked at
the nearest authorized Mercedes-Benz
Center.

167 Controls in detail
Audio system
Item
Page
1
CD mode selector
178
2
Manual tuning
(radio)
172
Fast forward/reverse
(cassette, CD)
176,
180
Speed dialing memory
(telephone*)
185
3
Radio mode selector
171
4
Display
Item
Page
5
Alpha-numeric keypadBand selection,
station buttons (radio)
171
CD selection (CD)
179
Telephone number entry,
retrieving speed dialing
memory (telephone*)
182
6
Scanning (radio, cas-
sette, CD)
173,
176,
180
7
Function button
172
8
Soft keys
168
Item
Page
9
Cassette eject
175
10
Cassette mode selector
174
11
Telephone* mode selec-
tor
182
12
Seek tuning (radio)
172
Track search (cassette,
CD)
175,
180
Speed dialing memory
(telephone*)
185
13
On /off
168
Volume
168

168 Controls in detailAudio systemButton and soft key operation
In these instructions, the alpha-numeric
keypad (right side of radio face) and the
function buttons (left side of the radio
face) are referred to as “buttons” and the
four keys under the display are referred to
as “soft keys”.Operation
Switching on/off
Switching on:
Turn the key to position1 or2 in the
starter switch.
or

Turn control knob
a
.Switching off:

Remove the key from the starter
switch.
or

Turn control knob
a
.
Adjusting the volume

Turn control knob
a
.
The volume will increase or decrease
according to the direction turned.Adjusting audio functions
In radio, cassette and CD mode, press
the AUD key to call up the bass, treble,
balance and fader functions.
Settings for bass and treble are stored sep-
arately for the AM (medium wave, long
wave, short wave) and FM (ultra-short
wave) frequency bands, cassette mode
and CD mode.
iDo not press directly on the radio dis-
play face.
iIf the radio is turned on without the key
in the ignition, it will automatically turn
off again after approx. 30 minutes.
iIf your vehicle was equipped with a
telephone* and voice control system*,
and both are connected to the car
radio, their volume can be adjusted
separately while the telephone* is
being used or voice control system* is
activated.