
ROnly use air-recirculation mode briefly, e.g.
if there are unpleasant outside odors or
when in a tunnel. The windows could oth-
erwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R If you change the settings of the climate
control system, the climate status display
appears for approximately three seconds
at the bottom of the screen in the Audio/
COMAND display (see separate operating
instructions). You will see the current set-
tings of the various climate control func-tions.
ECO start/stop function
During automatic engine switch-off, the cli-
mate control system only operates at a
reduced capacity. If you require the full cli-
mate control output, you can switch off the
ECO start/stop function by pressing the ECO
button ( Ypage 140).
122Overview of climate control systems
Climate control

Control panel for dual-zone automatic climate control
:Sets the temperature, left (Ypage 126)
;Sets climate control to automatic ( Ypage 126)
=Defrosts the windshield ( Ypage 128)
?Increases the airflow ( Ypage 127)
ASets the air distribution ( Ypage 127)
BDisplay
CActivates/deactivates air-recirculation mode ( Ypage 130)
DSwitches climate control on/off ( Ypage 124)
ESets the temperature, right ( Ypage 126)
FSwitches the residual heat function on/off ( Ypage 130)
GSwitches cooling with air dehumidification on/off ( Ypage 124)
HReduces the airflow ( Ypage 127)
ISwitches the rear window defroster on/off ( Ypage 129)
JSwitches the ZONE function on/off ( Ypage 127)
Optimum use of dual-zone climate
control
Climate control system
The following contains instructions and rec-
ommendations to enable you to get the most
out of your dual-zone automatic climate con- trol.
R Activate climate control using the Ãand
¿ buttons. The indicator lamps in the
à and¿ buttons light up.
R Set the temperature to 22 †. R
Only use the "Windshield defrosting" func-
tion briefly until the windshield is clear
again.
R Only use air-recirculation mode briefly, e.g.
if there are unpleasant outside odors or
when in a tunnel. The windows could oth-
erwise fog up, since no fresh air is drawn
into the vehicle in air-recirculation mode.
R Use the ZONE function to adopt the tem-
perature settings on the driver's side for
the front-passenger side as well. The indi-
cator lamp in the ábutton goes out.
Overview of climate control systems123
Climate control

RUse the residual heat function if you want to
heat or ventilate the vehicle interior when
the ignition is switched off. The residual
heat function can only be activated or deac- tivated with the ignition switched off.
R If you change the settings of the climate
control system, the climate status display
appears for approximately three seconds
at the bottom of the screen in the Audio/
COMAND display (see separate operating
instructions). You will see the current set-
tings of the various climate control func-tions.
ECO start/stop function
During automatic engine switch-off, the cli-
mate control system only operates at a
reduced capacity. If you require the full cli-
mate control output, you can switch off the
ECO start/stop function by pressing the ECO
button ( Ypage 140).
Operating the climate control sys- tems
Switching climate control on/off
General notes
When the climate control is switched off, the air supply and air circulation are also
switched off. The windows could fog up.
Therefore, switch off climate control onlybriefly
Air-conditioning system
X Turn the SmartKey to position 2in the igni-
tion lock ( Ypage 135).
X To switch on: turn controlAclockwise to
the desired position (except position 0)
( Y page 121).
X To switch off: turn controlAcounter-
clockwise to position 0(Y page 121).
Dual-zone automatic climate control
X
Turn the SmartKey to position 2in the igni-
tion lock ( Ypage 135).
X To activate: press theÃbutton.
The indicator lamp in the Ãbutton lights
up. Airflow and air distribution are set to
automatic mode.
or
X Press the ^button.
The indicator lamp in the ^button goes
out. The previously selected settings arerestored.
X To deactivate: press the^button.
The indicator lamp in the ^button lights
up.
iDual-zone automatic climate control:
switch on climate control primarily using the à button.
Activating/deactivating cooling with
air dehumidification
General notes
If you deactivate the "Cooling with air-dehu-
midification" function, the air inside the vehi- cle will not be cooled. The air inside the vehi-cle will also not be dehumidified. The win-
dows can fog up more quickly. Therefore, only
deactivate the "Cooling with air-dehumidifi-
cation" function briefly.
The "Cooling with air dehumidification" func-
tion is only available when the engine is run-
ning. The air inside the vehicle is cooled and
dehumidified according to the temperatureselected.
Condensation may drip from the underside of the vehicle when it is in cooling mode. This is
normal and not a sign that there is a malfunc- tion.
124Operating the climate control systems
Climate control

XTo deactivate: press theábutton.
The indicator lamp in the ábutton goes
out.
The temperature setting for the driver's
side is adopted for the front-passenger
side.
Defrosting the windshield
General notes
You can use this function to defrost the wind-
shield or to defrost the inside of the wind-
shield and the side windows.
iYou should only select the "Windshield
defrosting" function until the windshield is
clear again.
Activating/deactivating the defrosting
function for the windshield
X Turn the SmartKey to position 2in the igni-
tion lock ( Ypage 135).
X To activate: press the¬button.
The indicator lamp in the ¬button lights
up.
The climate control system switches to the
following functions:
R high airflow
R high temperature
R air distribution to the windshield and
front side windows
R air-recirculation mode off
iThe "Windshield defrosting" function
automatically sets the blower output to the optimum defrosting effect. As a result, the
airflow may increase or decrease automat-
ically after the ¬button is pressed.
iYou can adjust the blower output man-
ually while the "Windshield defrosting"
function is in operation: R
Air-conditioning system: turn airflow
control Acounter-clockwise or clock-
wise ( Ypage 121).
R Dual-zone automatic climate control:
press the óorô button.
X To deactivate: press the¬button.
The indicator lamp in the ¬button goes
out. The previously selected settings are
restored. Air-recirculation mode remains
deactivated.
or
X Dual-zone climate control: press the Ã
button.
The indicator lamp in the ¬button goes
out. Airflow and air distribution are set to
automatic mode.
or
X Air-conditioning system: turn temperature
control :counter-clockwise or clockwise
( Y page 121).
Dual-zone automatic climate control: turn
temperature control :orE counter-
clockwise or clockwise ( Ypage 123).
Defrosting the windows
Windows fogged up on the inside
Air-conditioning system
X Activate the ¿"Cooling with air dehu-
midification" function.
X If the windows continue to fog up, activate
the ¬ "Windshield defrosting" function.
iYou should only select this setting until
the windshield is clear again.
Dual-zone automatic climate control
X Activate the ¿"Cooling with air dehu-
midification" function.
X Activate automatic mode Ã.
X If the windows continue to fog up, activate
the ¬ "Windshield defrosting" function.
iYou should only select this setting until
the windshield is clear again.
128Operating the climate control systems
Climate control

Windows fogged up on the outside
XActivate the windshield wipers.
X Set the air distribution to PorO .
iYou should only select this setting until
the windshield is clear again.
Rear window defroster
General notes
The rear window defroster has a high current
draw. You should therefore switch it off as
soon as the rear window is clear. Otherwise,
the rear window defroster switches off auto-
matically after several minutes.
If the battery voltage is too low, the rear win-
dow defroster may switch off.
Switching on/off
X Turn the SmartKey to position 2in the igni-
tion lock ( Ypage 135).
X Press the ¤button.
The indicator lamp in the ¤button lights
up or goes out.
Operating the climate control systems129
Climate control

Problems with the rear window defroster
ProblemPossible causes/consequences andMSolutions
The rear window
defroster has deactiva-
ted prematurely or can-
not be activated.The battery has not been sufficiently charged.
X Switch off any consumers that are not required, e.g. reading
lamps, interior lighting or the seat heating.
When the battery is sufficiently charged, the rear window
defroster can be activated again.
Activating/deactivating air-recircula-
tion mode
General notes
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the vehi-
cle will then be recirculated.
If you switch on air-recirculation mode, the
windows can fog up more quickly, in particu-
lar at low temperatures. Only use air-recircu-
lation mode briefly to prevent the windows
from fogging up.
The operation of air-recirculation mode is the same for all control panels.
Switching on/off
X Turn the SmartKey to position 2in the igni-
tion lock ( Ypage 135).
X To activate: press theebutton.
The indicator lamp in the ebutton lights
up.
Air-recirculation mode switches on automat-
ically: R at high outside temperatures
R at high levels of pollution
When air-recirculation mode is activated
automatically, the indicator lamp in the e
button is not lit. Outside air is added after
about 30 minutes.
X To deactivate: press theebutton.
The indicator lamp in the ebutton goes
out.
iAir-recirculation mode deactivates auto-
matically:
R after approximately five minutes at out-
side temperatures below approximately
7 †
R after approximately five minutes if the
"Cooling with air dehumidification" func-
tion is deactivated
R after approximately 30 minutes at out-
side temperatures above approximately
7 † if the cooling with air dehumidifica-
tion function is activated
Activating/deactivating the residual
heat function
General notes
The residual heat function is only available
with dual-zone automatic climate control.
It is possible to make use of the residual heat
of the engine to continue heating the vehicle
for approximately 30 minutes after the engine
has been switched off. The heating time
depends on the set interior temperature.
iThe blower will run at a low speed regard-
less of the airflow setting.
iIf you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.
iYou cannot use the ventilation to cool the
vehicle interior to a temperature lower than the outside temperature.
130Operating the climate control systems
Climate control

Switching on/off
XTurn the key to position 0in the ignition
lock or remove it ( Ypage 135).
X To activate: press theÌbutton.
The indicator lamp in the Ìbutton lights
up.
X To deactivate: press theÌbutton.
The indicator lamp in the Ìbutton goes
out.
iResidual heat is deactivated automati-
cally:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops
Air vents
Important safety notes
GWARNING
Very hot or very cold air can flow from the air
vents. This could result in burns or frostbite in the immediate vicinity of the air vents. There
is a risk of injury.
Make sure that all vehicle occupants always
maintain a sufficient distance to the air out-
lets. If necessary, redirect the airflow to
another area of the vehicle interior.
In order to ensure the direct flow of fresh air
through the air vents into the vehicle interior,
please observe the following notes:
R keep the air inlet between the windshield
and the hood free of blockages, such as ice,
snow or leaves.
R never cover the air vents or air intake grilles
in the vehicle interior.
iYou can move the adjusters for the air
vents vertically or horizontally to set the
direction of the airflow.
iFor optimal climate control in the vehicle,
open the air vents completely and set the
adjusters to the central position.
Setting the center air vents
X To open the center air vents: turn the
adjuster in one of center air vents :coun-
ter-clockwise.
X To close the center air vent: turn the
adjuster in one of center air vents :clock-
wise as far as it will go.
Setting the side air vents
:Side window defroster vent
;Side air vent
X To open a side air vent: turn the adjuster
in side air vent ;to the left.
X To close a side air vent: turn the adjuster
in side air vent ;clockwise as far as it will
go.
Air vents131
Climate control
Z

XHold test gage Avertically on brake
disc :and slide measuring pin ;onto
brake disc :.
X Check which color field ?the arrow on
measuring pin ;is pointing to.
Green: the brake pad/lining thickness is
sufficient. Red: the brake pad/lining thickness is not
sufficient. Have the brake pads/lining
checked at a qualified specialist workshop.
To avoid an inaccurate measurement:
R make sure you position the wheels suitably
R do not put the measuring pin on a recess in
the brake disc
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if: R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or in conditions in which hydroplaning may occur,
you must drive in the following manner:
R lower your speed.
R avoid ruts.
R avoid sudden steering movements.
R brake carefully.
Driving on flooded roads
!Do not drive through flooded areas.
Check the depth of any water before driving through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic compo-
nents in the engine or the automatic trans-mission. Water can also be drawn in by the
engine's air suction nozzles and this can
cause engine damage.
Winter driving
GWARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
GDANGER
If the exhaust pipe is blocked or adequate
ventilation is not possible, poisonous gases
such as carbon monoxide (CO) may enter thevehicle. This is the case, e.g. if the vehicle
becomes trapped in snow. There is a risk of
fatal injury.
If you leave the engine or the auxiliary heating
running, make sure the exhaust pipe and area
around the vehicle are clear of snow. To
ensure an adequate supply of fresh air, open a window on the side of the vehicle that is not
facing into the wind.
Have your vehicle winter-proofed at a quali-
fied specialist workshop at the onset of win-ter.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering and braking maneuvers. Do not use the cruise
control or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:
X Shift the transmission to position N.
X Try to bring the vehicle under control using
corrective steering.
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Changes in the outside temperature are dis-
played after a short delay.
Indicated temperatures just above the freez-
ing point do not guarantee that the road sur-
face is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
160Driving tips
Driving and parking