Page 177 of 380
Climate control
Control panel
FunctionRecommendation/Notes:Temperature control, driver’s
side
iSet the temperature to 72‡
(22†).
(Y page 178);Air distribution and air volume
(automatic mode)
iSwitches on the automatic
mode. The indicator lamp in
button à comes on.
(Y page 178)=Front defrosteriKeep this setting selected
only until the windshield or the
side windows are clear again.
(Y page 179)?Increasing air volume(Y page 179)AAir distribution (directs air
through the windshield and side
air vents)
(Y page 178)BAC cooling on/offiSwitches on the air
conditioning. The indicator
lamp in button Á comes
on.
(Y page 177)Residual heat/ventilationiWith the engine turned off, it
is possible to continue to heat
or ventilate the interior.
(Y page 180)Climate control175Controls in detailX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 175Z
Page 178 of 380

FunctionRecommendation/NotesCTemperature control, passenger
sidei Set the temperature to 72‡
(22†).( Y page 178)D± Rear climate control on/
off or air supply for rear
passenger compartment on/off
(USA only)^ Rear climate control on/
off or air supply for rear
passenger compartment on/off
(Canada only)EAir distribution (directs air
through center and side air
vents)( Y page 178)FAir distribution (directs air
through the footwells and side
air vents)( Y page 178)GAir volume displayHDecreasing air volume(Y page 179)IRear window defroster(Y page 191)JAir recirculationi
Only use this function for a
short time, e.g. in a tunnel.
Otherwise, the windows can
fog up due to lack of fresh air.( Y page 180)KInterior temperature sensorLClimate control on/offi
Switches on the climate
control system. The indicator
lamp in button ^ goes out.(Y page 177)Notes on climate control
The climate control is operational whenever
the engine is running. You can operate the
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.Nearly all dust particles, pollutants and odors
are filtered out before outside air enters the
passenger compartment through the air
distribution system.GWarning!
Severe conditions (e.g. strong air pollution)
may require replacement of the filter before
its scheduled replacement interval. A clogged
filter will reduce the air volume to the interior
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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.
The air conditioning will not engage (no
cooling) if the A/C mode is deactivated
( Y page 177).GWarning!
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.
Keep the air intake grille in front of the
windshield free of snow and debris.
i If the vehicle interior is hot, ventilate the
interior before driving off, see “Summer
opening feature” (Y page 107). The climate
control will then adjust the interior
temperature to the set value much faster.
Deactivating the climate control
system
GWarning!
When the climate control system 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.
XDeactivating: Press button ^.
The indicator lamp in the button comes on.XReactivating: Press button Ã.
i
You can also press button ^ on the
climate control panel.
If you press button ¦ to reactivate the
climate control system, the defrosting
mode is activated.
Deactivating the rear climate control
from the frontXDeactivating: Press button ±.
The indicator lamp in the button comes on.XReactivating: Press button ±.
The indicator lamp in the button goes out.
Air conditioning
The air conditioning is operational while the
engine is running and cools the interior air to
the temperature set by the operator. In
addition, the air conditioning dehumidifies
the interior air and helps prevent window
fogging.
GWarning!
If you switch off the air conditioning, 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.
i Condensation may drip out from
underneath the vehicle. This is normal and
not an indication of a malfunction.
Deactivating
It is possible to deactivate the air
conditioning. The interior air will then no
longer be cooled or dehumidified.
XPress button Á.
The indicator lamp in 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 interior air with the air
conditioning.
XPress button Á again.
The indicator lamp in the button comes on.Climate control177Controls in detailX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 177Z
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The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs which
are harmful to the ozone layer.
! If the air conditioning cannot be activated
again, this indicates that the air
conditioning is losing refrigerant. The
compressor has turned off.
Have the air conditioning checked at the
nearest authorized Mercedes-Benz Center.
Automatic mode
When operating the climate control system in
automatic mode, the interior air temperature,
air volume and air distribution are adjusted
automatically.
In automatic mode, cooling with
dehumidification is switched on. This function
can be switched off if necessary.
GWarning!
If you switch off the air conditioning, 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.
XSet the desired temperature
( Y page 178).XActivating: Press button Ã.
The indicator lamp in the button comes on.
The air volume and air distribution are
adjusted automatically.
i The settings for the passenger side are
also used for the rear passenger
compartment.
XDeactivating: Press button I or K .
The indicator lamp in button à goes out.
The automatic operation of air volume
switches off. The selected blower speed isshown in air volume display G
( Y page 175).
or
XPress air distribution button ¯, P , or
O .
The indicator lamp in button à goes out.
The automatic operation of air distribution
switches off.
Setting the temperature
You can 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‡ (22†).
XIncreasing/decreasing: Turn
temperature control : and/or C
( Y page 175) slightly clockwise or
counterclockwise.
Adjusting air distribution
The air distribution can be adjusted manually.
The symbols on the buttons represent the
following functions:
SymbolFunction¯Directs air to the windshield and
side air ventsPDirects air through the center
and side air ventsODirects air to the footwells and
side air ventsXPress the desired air distribution button
¯ , P , or O .
The indicator lamp in button à goes out.
The automatic mode is switched off. Air
distribution is controlled according to the
desired button.178Climate controlControls in detail
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Adjusting air volumeXDecreasing/increasing: Press button
I or K .
The automatic mode is switched off. The
selected blower speed is shown in air
volume display G (Y page 175).
When using the Voice Control System, the
blower speed reduces automatically. When
the Voice Control System is not used
anymore, the blower speed increases to the
previously selected level.
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.
i Keep this setting selected only until the
windshield or the side windows are clear
again.
Activating
XPress button ¦.
The indicator lamp in the button comes on.
The climate control switches to the
following functions automatically:
R most efficient blower speed and heating
power, depending on outside
temperature
R air flows onto the windshield and the
front door windows (side air vents must
be open)
R the air conditioning compressor
switches on at outside temperatures
above approximately 41‡ (5†) for air-
drying
Adjustments
You can adjust the air volume and the
temperature when the front defroster is
switched on. The air flow will remain on the
windshield and front door windows.
XPress button I to decrease or button
K to increase air volume to the desired
level.
The air volume decreases/increases to the
next lower/higher blower speed and
heating switches to the temperature that
was set before the front defroster was
switched on.
The indicator lamp in button ¦ goes out.
The indicator lamp in button Á comes
on.
or
XTurn temperature control : and/or C
( Y page 175) slightly in any direction.
Heating switches to the temperature that
was set before the front defroster was
switched on.
The indicator lamp in button ¦ goes out.
The indicator lamp in button Á comes
on.
i The air conditioning compressor remains
on even if the indicator lamp in button
¦ goes out. This helps to prevent the
windshield from fogging.
Deactivating
XPress button ¦ again.
The indicator lamp in the button goes out.
Defrosting is turned off.
The previous settings are once again in
effect. The air conditioning compressor
remains switched on.
i To deactivate, you can also press button
^ or à .
Windshield fogged on the outside
XSwitch the windshield wipers on
( Y page 103).XPress air distribution button P or O .Climate control179Controls in detailX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 179Z
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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.GWarning!
Fogged windows impair visibility,
endangering 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 is activated, or press button
¦ .
XActivating: Press button d.
The indicator lamp in the button comes on.
i The air recirculation mode is activated
automatically at high outside
temperatures.
The indicator lamp in button d is not lit
when the air recirculation mode is switched
on automatically.
A quantity of outside air is added after
approximately 30 minutes.
If you have turned off the air conditioning
or the outside temperature is below 41‡
(5†), the air recirculation mode will not
switch on automatically.
XDeactivating: Press button d.
The indicator lamp in the button goes out.i The manually selected air recirculation
mode is deactivated automatically:
R after 5 minutes if the outside
temperature is below approximately
41‡ (5†)
R after 5 minutes if the air conditioning and
air-drying are turned off
R after 30 minutes if the outside
temperature is above approximately
41‡ (5†)
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.
i How long the system will provide heating
depends on the coolant temperature and
the battery voltage.
Regardless of the temperature and air
volume set on the climate control panel, an
interior temperature is aimed at by 72‡
(22† ) and the blower runs on low speed to
protect the vehicle battery.
XActivating: Switch off the ignition.XPress button Á.
The indicator lamp in the button comes on.XDeactivating: Press button Á again.
The indicator lamp in the button goes out.
The residual heat is deactivated automatically
R when the ignition is switched on
R after approximately 30 minutes
R if the battery voltage drops
R if the coolant temperature is too low
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3-zone automatic climate control
Control panels
USA onlyFunctionRecommendation/Notes:Temperature control, driver’s
side
iSet the temperature to 72‡
(22†).
(Y page 187);Air distribution and air volume
(automatic mode)
iSwitches on the automatic
mode. The indicator lamp in
button à comes on.
(Y page 187)=Front defrosteriKeep this setting selected
only until the windshield or the
side windows are clear again.
(Y page 189)?Increasing air volume(Y page 189)AAir distribution (directs air
through the windshield and side
air vents)
(Y page 188)3-zone automatic climate control181Controls in detailX164_AKB; 5; 31, en-USd2ureepe,Version: 2.11.8.12009-09-11T12:30:16+02:00 - Seite 181Z
Page 184 of 380

FunctionRecommendation/NotesBAC cooling on/offiSwitches on the air
conditioning. The indicator
lamp in button Á comes
on.( Y page 186)Residual heat/ventilationi
With the engine turned off, it
is possible to continue to heat
or ventilate the interior.( Y page 191)CTemperature control, passenger
sidei Set the temperature to 72‡
(22†).( Y page 187)DOperating the rear climate
control from the front( Y page 186)EAir distribution (directs air
through center and side air
vents)( Y page 188)FAir distribution (directs air
through the footwells and side
air vents)( Y page 188)GAir volume displayHDecreasing air volume(Y page 189)IRear window defroster(Y page 191)JAir recirculationi
Only use this function for a
short time, e.g. in a tunnel.
Otherwise, the windows can
fog up due to lack of fresh air.( Y page 190)KInterior temperature sensorLClimate control on/offi
Switches on the climate
control system. The indicator
lamp in button ^ goes out.(Y page 185)1823-zone automatic climate controlControls in detail
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