2003 MERCEDES-BENZ C320 4MATIC climate control

153 Controls in detail
Climate control
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.Deactivating the climate control
system
Deactivating
Set the air volume control
(page 149) to position 0.
Reactivating

Set the air volume control
(page 149) to any speed.
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.

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.

155 Controls in detail
Climate control
Ventilated storage compartment
The front center console storage compart-
ment has its own air vent that allows for
cooling ventilation when the automatic cli-
mate control system is activated.
1LeverOpening the air vent

Raise lever1.
Closing the air vent

Lower lever1.Rear passenger compartment adjust-
able air vents
1Center air vent, left
2Thumbwheel for air volume control for
center air vents
3Center air vent, right
To open center air vents:
Turn thumbwheel2 upward.
iYou should keep this air vent closed
when outside temperatures are low.
iThe compartment can get very warm
due to its confined space. When storing
heat sensitive objects in the compart-
ment, close the air vent while heating
the passenger compartment.!Do not obstruct the air vent in the
storage compartment.
iThe temperature at the air vents for the
rear passenger compartment1 and3
is the same as at the dashboard center
air vents.

156 Controls in detailAutomatic climate control*
Automatic climate control*

157 Controls in detail
Automatic climate control*
Automatic climate control panel
Item
1
Air volume control for left center air
vent
2
Left center air vent, adjustable
3
Thumbwheel for adding outside air
4
Right center air vent, adjustable
5
Air volume control for right center
air vent
6
Air volume control for side air vent
7
Side air vent, adjustable
8
Side defroster vent, fixed
9
Automatic climate control paneliFor draft-free ventilation, move the slid-
ers for the center air vents to the mid-
dle position.
Item
1
Temperature control, left, raising
2
Left-side air distribution control
(automatic or manual operation)
3
Activated charcoal filter
4
Display
5
Right-side air distribution control
(automatic or manual operation)
6
Temperature control, right, raising
7
Temperature control, right,
lowering
8
Rear window defroster
9
AC cooling on/off (AC
OFF
)
Residual heat/ventilation
10
Air volume control
11
Automatic climate control on/off
(complete system)
12
Air recirculation
13
Defrosting
14
Temperature control, left, lowering

158 Controls in detailAutomatic climate control*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 en-
ters the passenger compartment through
the air distribution system.
The air conditioning will not engage (no
cooling) if theAC
OFF
mode is selected
(
page 149).
Setting the temperature
Use temperature controls1 and14 for the
left side or6 and7 for the right side to
separately adjust the air temperature on
each side of the passenger compartment.
You should raise or lower the temperature
setting in small increments, preferably
starting at 72°F (22°C).Increasing

Push temperature control1 and/or6.
The automatic climate control system
will correspondingly adjust the interior
air temperature.
Decreasing

Push temperature control7
and/or14.
The automatic climate control system
will correspondingly adjust the interior
air temperature.
Adding outside air

Turn thumbwheel3 in dashboard
(page 156) to increase airflow of out-
side air through air vents for center, left
and right sides and rear passenger
compartment.
Warning!
G
Follow the recommended settings for heat-
ing and cooling given on the following pag-
es. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.
iIf the vehicle interior is hot, ventilate
the interior before driving off.
Keep the air intake grille in front of the
windshield free of snow and debris.
Do not obstruct air flow by placing ob-
jects on the air flow-through exhaust
slots below the rear window.iWhen operating the climate control
system in automatic mode, you will
only rarely need to adjust the tempera-
ture, air volume and air distribution.

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.