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166 Automatic climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Display and controls
1Defrosting
2Rear window defroster, see page 180
3Residual engine heat utilization, see page 174
4Automatic climate control on / off
5Air distribution, right (automatic, manual operation)
6Economy mode, see page 173
7Temperature control, right8Air volume (automatic, manual)
9Display
Depending on the ambient light conditions, the
figures on the display will be shown as dark figures
on a bright background (in daylight), or as bright
figures on a dark background (at night).
10Temperature control, left
11Air recirculation, see page 171
12Air distribution, left (automatic, manual operation)
13Activated charcoal filter
Important!
This vehicle is equipped with an air conditioning
system that uses R-134a (HFC: hydrofluorocarbon) as a
refrigerant. Repairs should always be performed by a
qualified technician, and refrigerant should be collected
in a recovery system for recycling.
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167 Automatic climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Automatic climate control
The system is always at operational readiness, except
when manually switched off.
The automatic climate control only operates with the
engine running.
The temperature selector should be left at the desired
temperature setting. The temperature selected is
reached as quickly as possible.
Th e system w il l not hea t or c ool a ny q uicker by setting a
higher or lower temperature.
The desired interior temperature and air distribution
can be selected separately for the left and right side of
the passenger compartment.
The automatic climate control removes considerable
moisture from the air during operation in the cooling
mode. It is normal for water to drip on the ground
through ducts in the underbody.
The air conditioning will not engage (no cooling) if the
economy mode S is selected, see page 173. Notes:
Do not obstruct the air flow by placing objects on the air
flow-through exhaust slots below the rear window.
Also keep the air intake grill in front of the windshield
free of snow and debris.
The storage compartment between the front seats can be
ventilated. See page 175 for notes on ventilating the
storage space under the armrest in the center console.
The air conditioner switches itself off for its own
protection if refrigerant is lost. No cooling will then take
place. Economy mode S cannot be switched off. Have
the air conditioner checked by a Mercedes-Benz Center
should this happen.
Dust filter
Nearly all dust particles and pollen are filtered out
before outside air enters the passenger compartment
through the air distribution system.
Page 173 of 421
170 Automatic climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Defrosting
Press the P button. The display shows P.
The fan is set to a higher speed and the warm air is
directed to the defroster and windshield air outlets.
Pressing the switch again returns the system to the
previous setting.Windows fogged on the inside
Switch off the economy mode, if selected: Press
buttonS. The indicator lamp in the button will go
out.
Switch off air recirculation, if selected: Press
buttonO. The indicator lamp in the button will go
out.
Adjust left and right air outlets upwards.
Set blower to the maximum blower speed.
Increase temperature setting.
Open the side air outlets and direct them onto the side
windows.
P83.40-2009-21
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171 Automatic climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Windshield fogged on the outside
Switch on the windshield wiper.
Press on both U buttons until they click in. The
h, j and k symbols will no longer be visible.
Air recirculation
Select air recirculation:
The indicator lamp in the O button is off.
Press button O briefly. The indicator lamp in the
button illuminates.
To switch off the air recirculation:
The indicator lamp in the O button is on.
Press button O briefly. The indicator lamp in the
button will go out.
Switching on air recirculation and activating
convenience closing:
The indicator lamp in the O button is off.
Press button O for more than 2 seconds, the side
windows and the sliding / pop-up roof will be closed. The
indicator lamp in the button lights up.
Switching off air recirculation and activating
convenience opening:The indicator lamp in the O button is on.
Press button O for more than 2 seconds, the side
windows and the sliding / pop-up roof return to the
position they were in before closing.
A window or the sliding / pop-up roof opened manually
after convenience closing will no longer be returned to
the position it was in before closing when convenience
opening is selected.
The system automatically switches from air
recirculation to fresh air:
•after 30 minutes if the outside temperature is above
about 40°F(5°C),
•after 5 minutes if the outside temperature is below
about 40°F(5°C),
•after 5 minutes if economy mode S is selected.
The system switches automatically to air recirculation at
high outside temperatures. A quantity of outside air is
added after about 30 minutes.
If the windows should fog up from the inside, switch
from recirculated air back to fresh air.
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172 Automatic climate control
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cluster displayPractical hints Car care Index
Activated charcoal filter
An activated charcoal filter markedly reduces bad odors
and removes pollutants from air entering the passenger
compartment.
To select, press e button. The indicator lamp in the
button illuminates.
To cancel, press button. The indicator lamp in the button
goes out.
The system switches automatically to the air
recirculation mode, if the carbon monoxide (CO) or
nitrogen oxides (NO
X) concentration of the outside air
increases beyond a predetermined level.
The automatic air recirculation mode does not function
if economy mode S is selected or if the outside
temperature has fallen below 40°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.Switching on the activated carbon filter and activating
convenience closing:
The indicator lamp in the e button is off.
Press button e for more than 2 seconds, the side
windows and the sliding / pop-up roof will be closed. The
indicator lamp in the button lights up.
Switching off activated carbon filter and activating
convenience opening:
The indicator lamp in the e button is on.
Press button e for more than 2 seconds, the side
windows and the sliding / pop-up roof return to the
position they were in before closing.
A window or the sliding / pop-up roof opened manually
after convenience closing will no longer be returned to
the position it was in before closing when convenience
opening is selected.
Page 176 of 421
173 Automatic climate control
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Economy mode
The function of this setting corresponds to the
automatic mode. However, because the air conditioning
compressor will not engage (fuel savings), it is not
possible to air condition in this setting.Press S button to activate. The indicator lamp in the
button illuminates.
Press S button once again to return to the previous
setting.
Important!
In the S mode the windows could fog up on the
inside. Switch off S mode.
Page 179 of 421
176 Automatic climate control
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data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Rear passenger compartment adjustable air outlets
1Center air outlet, left
2Center air outlet, right
3Air volume control for center air outlets
(vehicles without rear air conditioner)
To open: Turn the wheel to the left.4Rear side air outlet, right and left
5Air volume control for rear side air outlet
To open: Turn thumbwheel towards the window.
P83.00-0372-26
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180 Automatic climate control
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and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Rear window defroster
Turn the electronic key in starter switch to position 2.
To s elec t:
Press the F button in the control panel of the
automatic air conditioner. The indicator lamp in the
button illuminates.
To ca nc el:
Press the F button in the control panel of the
automatic air conditioner. The indicator lamp in the
button goes out.
Note:
Heavy accumulation of snow and ice should be removed
before activating the defroster. The rear window defroster uses a large amount of power.
To keep the battery drain to a minimum, turn off the
defroster as soon as the rear window is clear.
The defroster is automatically turned off after
approximately 6–23 minutes of operation depending on
the outside temperature and vehicle speed.
If several power consumers are turned on
simultaneously, or the battery is only partially charged,
it is possible that the defroster will automatically turn
itself off. When this happens, the indicator lamp inside
the switch starts blinking.
As soon as the battery has sufficient voltage, the
defroster automatically turns itself back on.