2008 MERCEDES-BENZ C300 Temperature

257 Controls in detail
Dual-zone automatic climate control
Deactivating: Press button¯
(
page 250).
The indicator lamp in the button goes
out.
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 250).
The indicator lamp in the button comes
on.
Deactivating: Press button,
(
page 250) again.
The indicator lamp in the button goes
out.
iThe rear window defroster is automatically
deactivated after some time of operation de-
pending on the outside temperature.
iIf the rear window defroster switches off too
soon and the indicator lamp goes out, this indi-
cates that too many electrical consumers are op-
erating simultaneously and the load on the
battery is reducing available voltage. The system
responds automatically by deactivating the rear
window defroster.
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 258) is activated, or
press buttony.
iThe air recirculation mode is activated auto-
matically at high outside temperatures.
The indicator lamp in 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.
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)

259 Controls in detail
3-zone automatic climate control* (Canada only)
3-zone automatic climate control* (Canada only)
3-zone automatic climate control panel, front
Item
1Temperature control, driver’s side
2UAir distribution and air vol-
ume (automatic mode)
3´Automatic climate control
on/off
4zAdopting driver’s side set-
tings for all zones
Item
52AC cooling on/off
6TResidual engine
heat/ventilation
7yFront defroster
8Temperature control, passenger side
9¯Rear window defroster
Item
aZAir distribution, passenger
side
bQIncreasing air volume
c·Decreasing air volume
dDisplay
eZAir distribution, driver’s side
f,Air recirculation

260 Controls in detail
3-zone automatic climate control* (Canada only)
The 3-zone automatic climate control is
operational whenever the engine is run-
ning. You can operate the 3-zone automat-
ic climate control system in either the
automatic or manual mode. The system
cools or heats the interior depending on
the selected interior temperature and the
current outside temperature.
It can only function optimally when you are
driving with the windows and the tilt/slid-
ing sunroof/panorama sunroof* closed.It is possible to completely deactivate the
3-zone automatic climate control system
(
page 261).
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 the A/C mode is deactivated
(
page 267).
Warning!G
When operating the 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 frostbite on unpro-
tected skin in the immediate area of the air
vents. Always keep sufficient distance be-
tween unprotected parts of the body and the
air vents. If necessary, use the air
distribution control (page 248) to direct
the air to air vents in the vehicle interior that
are not in the immediate area of unprotect-
ed skin.
Warning!G
Severe 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 and the
windows could fog up, impairing visibility
and endangering you and others. Have a
clogged filter replaced as soon as possible
at an authorized Mercedes-Benz Center.
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.
iKeep 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.
iIf the vehicle interior is hot, ventilate the in-
terior before driving off, see “Summer opening
feature” (
page 123). The climate control will
then adjust the interior temperature to the set
value much faster.

261 Controls in detail
3-zone automatic climate control* (Canada only)
Deactivating climate control system
Deactivating: Press button´
(
page 259).
The indicator lamp in the button comes
on.
Reactivating: Make sure the ignition is
switched on.
Press button´ (page 259) again.
The indicator lamp in the button goes
out.The previous settings are once
again in effect.
or,
Press buttonU (page 259) while
the engine is running.
The indicator lamp in the button comes
on. The air volume and air distribution
are adjusted automatically.Operating climate control system in
automatic mode
Activating: Press buttonU
(
page 259) while the engine is run-
ning.
The indicator lamp in the button comes
on. The air volume and air distribution
are adjusted automatically.
Use temperature controls1 and8
(
page 259) to separately adjust the
air temperature on each side of the
passenger compartment.
The temperature of the vehicle interior
is adjusted automatically.
Warning!G
When the climate control is switched off, the
outside air supply and circulation are also
switched off. Only choose this setting for a
short time. Otherwise the windows could
fog up, impairing visibility and endangering
you and others.
iWhen operating the climate control system
in automatic mode, you will only rarely need to
adjust the temperature, air volume and air distri-
bution.
In automatic mode, cooling with dehumidify is
switched on. This function can be switched off if
necessary.

262 Controls in detail
3-zone automatic climate control* (Canada only)
Deactivating: Press buttonU
(
page 259) again.
The indicator lamp in the button goes
out. The automatic operation of air vol-
ume and air distribution switches off.
The symbols of air distribution and air
volume appear in displayd.
Adjust air distribution (page 263).
Adjust air volume (page 263).
Setting the temperature
Use temperature controls1 and/or8
(
page 259) to separately adjust the air
temperature on each side of the passenger
compartment. You should raise or lower
the temperature setting in small incre-
ments, preferably starting at 72°F (22°C).
The climate control will adjust to the set
temperature as fast as possible.
Increasing: Turn temperature
control1 and/or8 (
page 259)
slightly clockwise.
The climate control system will corre-
spondingly adjust the interior air tem-
perature.
Decreasing: Turn temperature
control1 and/or8 (
page 259)
slightly counterclockwise.
The climate control system will corre-
spondingly adjust the interior air tem-
perature.
iYou can also adjust the temperature in the
rear passenger compartment (
page 268).
iIf you turn the temperature control fully
clockwise for one side of the vehicle, you are in-
creasing the temperature for the other side of
the vehicle as well.
iIf you turn the temperature control fully
counterclockwise for one side of the vehicle, you
are decreasing the temperature for the other
side of the vehicle as well.

263 Controls in detail
3-zone automatic climate control* (Canada only)
Adjusting air distribution
Use righta and/or lefte buttonZ
(
page 259) to adjust the air distribution
manually for each side of the passenger
compartment. The following symbols are
shown in displayd:
Press buttonsZ (page 259) re-
peatedly until you have select the de-
sired setting and the corresponding
symbol is shown in displayd.The indicator lamp in buttonU goes
out. The automatic air distribution is
switched off. The air distribution is
controlled according to the selected
control setting.
Adjusting air volume
Use buttonU (
page 259) for auto-
matic mode or button · (
page 259)
orQ (
page 259) to adjust air volume
manually.
Seven blower speeds are available for each
side of the passenger compartment.
Press button· to decrease, or
buttonQ to increase air volume to
the desired level.
The indicator lamp in buttonU
(
page 259) goes out.
The air volume is adjusted correspond-
ing to the set blower speed. The auto-
matic air distribution remains switched
on.Using driver-side settings for all tem-
perature zones
You can use the settings of the driver’s
side, such as temperature, air volume and
air distribution, for all temperature zones.
Press buttonz (page 259).
The indicator lamp in the button comes
on.
The driver-side settings are used for all
temperature zones.
SymbolFunction
{Directs air to the windshield
and the side defroster vents
aDirects air through the center,
side and rear passenger
compartment air vents
YDirects air to the footwells
iYou can also select a position between two
symbols with buttonZ.

264 Controls in detail
3-zone automatic climate control* (Canada only)
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 buttony
(
page 259).
The indicator lamp in the button comes
on.
The air conditioning switches
automatically to the following functions:

cooling on to dehumidify

most efficient blower speed and
heating power, depending on out-
side temperature

air flows onto the windshield and
the front side windows

the air recirculation mode is
switched off
Deactivating: Press buttony
(
page 259) again.
The indicator lamp in the button goes
out. Defrosting is turned off.
The previous settings are once again in
effect.Windshield fogged on the outsideSwitch the windshield wipers on
(
page 118).
If the automatic mode of the climate con-
trol is switched off:
Press righta and/or lefte air distri-
bution buttonZ (
page 259) re-
peatedly until one of the following
symbols appears in
displayd:aorY
(
page 259).
iKeep this setting selected only until the
windshield is clear again.
iYou can adjust the air distribution when the
front defroster is switched on.
iTo switch defrosting off, you can also press
button´, U,·,Q or temperature
controls1 and8 (
page 259).
iThe cooling remains switched on.
iKeep this setting selected only until the
windshield is clear again.

265 Controls in detail
3-zone automatic climate control* (Canada only)
Rear window defroster
Activating: Switch on the ignition.
Press button¯ (page 259).
The indicator lamp in the button comes
on.
Deactivating: Press button¯
(
page 259).
The indicator lamp in the button goes
out.
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.
!The rear window defroster uses a large
amount of power. To keep battery drain to a min-
imum, switch off the defroster as soon as the
rear window is clear.
iThe rear window defroster is automatically
deactivated after some time of operation de-
pending on the outside temperature.
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.
iIf the rear window defroster switches off too
soon and the indicator lamp goes out, this indi-
cates that too many electrical consumers are op-
erating simultaneously and the load on the
battery is reducing available voltage. The system
responds automatically by deactivating the rear
window defroster.
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 267) is activated, or
press buttony.