2012 MERCEDES-BENZ R-Class Owner's Manual

Switching the front climate control on/
off using the front control panelXTurn the SmartKey to position 2 in the
ignition lock.XTo switch on: press the à button.
The indicator lamp in the à button lights
up. Airflow and air distribution are set to
automatic mode.
or
XPress the ^ button.
The indicator lamp in the ^ button goes
out. The previously selected settings come
into effect again.XTo switch off: press the ^ button.
The indicator lamp in the ^ button lights
up.
Switching the rear-compartment
climate control on/off using the front
control panel
2-zone automatic climate control
XTurn the SmartKey to position 2 in the
ignition lock.XTo switch on/off: press the ± button.
The indicator lamp in the ± button lights
up or goes out.
3-zone automatic climate control
USA only:
XTurn the SmartKey to position 2 in the
ignition lock.XTo switch on/off: press the ± button.
The indicator lamp in the ± button lights
up or goes out.
Canada only:
XTurn the SmartKey to position 2 in the
ignition lock.XTo switch on: press the Y button.
ON and MODE are shown in the automatic
climate control display behind the Y
symbol. The MODE display goes out after
three seconds. The display switches back
to the standard display.XTo switch off: press the Y button.
MODE is shown in the display behind the
Y symbol.XPress button ^.
OFF is shown in the display behind the
Y symbol.
Switching the rear-compartment
climate control on/off using the rear
control panel
3-zone automatic climate control
XTurn the SmartKey to position 2 in the
ignition lock.XSwitch on automatic climate control using
the front control panel.XTo switch on: press the à button.
The indicator lamp in the à button lights
up.XTo switch off: press the ^ button.
The indicator lamp in the ^ button lights
up.
Activating/deactivating the cooling
with air dehumidification function
Important information
The cooling with air dehumidification function
is only available when the engine is running.
The air inside the vehicle is cooled and
dehumidified according to the temperature
selected.
GWARNING
If you switch off the cooling function, 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.
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
malfunction.
Operating the climate control system135Climate controlZ

iThe cooling with air dehumidification
function uses refrigerant R134a. This
coolant does not contain
chlorofluorocarbons, and therefore does
not damage the ozone layer.
Activating/deactivating
! If the cooling with air dehumidification
does not switch on, it is possible that the
climate control system has lost coolant.
Have the cooling with air dehumidification
checked at a qualified specialist workshop.
XTo activate: press the Á button.
The indicator lamp in the Á button lights
up.XTo switch off: press the Á button.
The indicator lamp in the Á button goes
out. The cooling with air dehumidification
function has a delayed switch-off feature.
Problems with the cooling with air
dehumidification function
If the indicator lamp in the Á button does
not go out when the function is activated, the
cooling with air dehumidification function is
deactivated due to a malfunction. You can no
longer switch on the cooling with air
dehumidification function.
XConsult a qualified specialist workshop.
Setting climate control to automatic
GWARNING
If you switch off the cooling function, 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.
In automatic mode, the set temperature is
maintained automatically at a constant level.
The system automatically regulates the
temperature of the dispensed air, the airflow
and the air distribution.
Automatic mode will achieve optimal
operation if cooling with air dehumidification
is also activated. If desired, cooling with air
dehumidification can be deactivated.
Controlling the front climate control
using the front control panelXTurn the SmartKey to position 2 in the
ignition lock.XSet the desired temperature.XTo activate: press the à button.
The indicator lamp in the à button lights
up. Automatic air distribution and airflow
are activated.XTo deactivate: press the K or I
button.
The indicator lamp in the à button goes
out. Automatic airflow is deactivated and
the airflow is controlled according to the
level set. Automatic air distribution
remains activated.
or
XPress the Z, M , ¯ , \ , P ,
c or O button.
The indicator lamp in the à button goes
out. Automatic air distribution is
deactivated. Air distribution is controlled
according to the position set. Automatic
airflow remains activated.
Controlling the rear-compartment
climate control automatically using the
rear control panel
XTurn the SmartKey to position 2 in the
ignition lock.XSwitch on automatic climate control using
the front control panel.XSet the desired temperature.XTo activate: press the à button.
The indicator lamp in the à button lights
up. Automatic air distribution and airflow
are activated.136Operating the climate control systemClimate control

XTo deactivate: press the K or I
button.
Automatic airflow is deactivated and the
airflow is controlled according to the level
set. Automatic air distribution remains
activated.
or
XPress one of the M or O buttons.
Automatic air distribution is deactivated.
Air distribution is controlled according to
the position set. Automatic airflow remains
activated.
Setting the temperature
2-zone automatic climate control
Different temperatures can be set for the
driver's and front-passenger sides.
XTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: turn controls : and
C clockwise or counter-clockwise
( Y page 131).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 †).
3-zone automatic climate control
Automatic climate control climate zones
You can select different temperature settings
for the driver's and front-passenger sides as
well as for the rear compartment.
XTo increase/reduce the front-
compartment temperature using the
front control unit: turn the SmartKey in
the ignition lock to position 2.XTurn controls : and C15
/E 16
clockwise
or counter-clockwise ( Y page 132).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 †).
USA only:
XTo increase/reduce the rear-
compartment temperature using the
front control unit: turn the SmartKey in
the ignition lock to position 2.XPress the ± button.XTurn control C clockwise or counter-
clockwise ( Y page 132).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 †).
Canada only:
XTo increase/reduce the rear-
compartment temperature using the
front control unit: turn the SmartKey in
the ignition lock to position 2.XPress the Y button.
The display changes to rear-compartment
climate control.XTurn control E clockwise or counter-
clockwise ( Y page 132).
Only change the temperature setting in
small increments. Start at 72 ‡ (22 †).
i To return to the standard display, press
the Y button.
i The rear display changes to the standard
display automatically after three seconds.
XTo increase/reduce the temperature in
the rear compartment using the rear
control panel: turn the SmartKey in the
ignition lock to position 2.XTurn control N15
/R 16
clockwise or
counter-clockwise ( Y page 132).15
USA only.
16 Canada only.Operating the climate control system137Climate controlZ

Only change the temperature setting in
small increments. Start at 72 ‡ (22 †).
Setting the air distribution
Air distribution settings
Automatic climate control: the air distribution
can be set individually for the driver's and
front-passenger sides. 17
Front control unit:
ZDirects the airflow through the
defroster ventsMDirects the airflow through the
defroster vents¯Directs the airflow through the
defroster ventscDirects the airflow through the
footwell and side air ventsODirects the airflow through the
footwell and side air vents\Directs the airflow through the center
and side air ventsPDirects the airflow through the center
and side air vents
Rear control panel:
MDirects the airflow through the rear-
compartment air ventsODirects the airflow through the
footwell air vents
Adjusting
XTurn the SmartKey to position 2 in the
ignition lock.XPress the Z, M , ¯ , c , O ,
\ or P button.Setting the airflowXTurn the SmartKey to position 2 in the
ignition lock.XTo increase/reduce: press the K or
I button.
Vehicles with Voice Control System: when the
Voice Control System is switched on, the
airflow is restricted to 50%. When command
input is complete, the airflow is adjusted back
to the previous setting.
Activating/deactivating the MONO
function
The MONO function is only available with
automatic climate control. 18
You can use the MONO function to adopt the
settings configured for temperature, air
distribution and airflow on the driver's side for
the front-passenger side and the rear
compartment.
XPress the º button.
The indicator lamp in the º button lights
up or goes out.
Defrosting the windshield
You can use this function to defrost the
windshield or to defrost the inside of the
windshield and the side windows.
i You should only select the defrosting
function until the windshield is clear again.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the ¦ button.
The indicator lamp in the ¦ button lights
up.17 Canada only.
18 Canada only.138Operating the climate control systemClimate control

The climate control system switches to the
following functions:
R cooling with air dehumidification on
R high airflow 19
R high temperature 19
R air distribution to the windshield and
front side windows
R air-recirculation mode offXTo switch off: press the ¦ button.
The indicator lamp in the ¦ button goes
out. The previously selected settings come
into effect again. The cooling with air
dehumidification function remains on. Air-
recirculation mode remains deactivated.
or
XPress the ^ button.
or
XPress the à button.
or
XTurn the temperature control clockwise or
counter-clockwise.
or
XPress the K or I button.
Defrosting the windows
Windows fogged up on the inside
XActivate the cooling with air
dehumidification function Á.XActivate automatic mode Ã.XIf the windows continue to fog up, activate
the defrosting function ( Y page 138).
i
You should only select this setting until
the windshield is clear again.
Windows fogged up on the outsideXSwitch on the windshield wipers.XPress the P/\ 20
or O /c 20
air distribution button.
i You should only select this setting until
the windshield is clear again.
Rear window defroster
Activating/deactivating
GWARNING
Any accumulation of snow and ice should be
removed from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window defroster has a high current
draw. You should therefore switch it off as
soon as the window is clear as it only switches
off automatically after several minutes.
If the battery voltage is too low, the rear
window defroster may switch off.
XTurn the SmartKey to position 2 in the
ignition lock.XPress the ª button.
The indicator lamp in the ª button lights
up or goes out.
Problems with the rear window
defroster
If the indicator lamp in the ª rear window
defroster button flashes, the on-board
voltage is too low or the roof is open. The rear
window defroster has deactivated itself
prematurely or cannot be activated.
XSwitch off any consumers that are not
required, e.g. reading lamps or interior
lighting.
When the battery is sufficiently charged,
the rear window defroster is activated
again automatically.19 Depending on the outside temperature.
20 Canada only.Operating the climate control system139Climate controlZ

Activating/deactivating air-
recirculation mode
You can deactivate the flow of fresh air if
unpleasant odors are entering the vehicle
from outside. The air already inside the
vehicle will then be recirculated.
The operation of air-recirculation mode is the
same for all control panels.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 the ¬
button.
XTurn the SmartKey to position 2 in the
ignition lock.XTo activate: press the d button.
The indicator lamp in the d button lights
up.
i Air-recirculation mode is activated
automatically at high outside
temperatures. When air-recirculation mode
is activated automatically, the indicator
lamp in the d button is not lit.
Outside air is added after about 30
minutes.
XTo switch off: press the d button.
The indicator lamp in the d button goes
out.i Air-recirculation mode deactivates
automatically:
R after approximately five minutes if
outside temperatures are less than about
41 ‡ (5 †)
R after approximately five minutes if
cooling with air dehumidification is
deactivated
R after approximately 30 minutes if outside
temperatures are over about
41 ‡ (5 †)
i The air-recirculation mode is not
deactivated automatically at outside
temperatures above 79 ‡ (26 †). After
approximately 30 minutes, outside air is
added. 21
Activating/deactivating the residual
heat function
It is possible to make use of the residual heat
of the engine to continue heating the
stationary vehicle for up to 30 minutes after
the engine has been switched off. The heating
time depends on the temperature that has
been set.
i The blower will run at a low speed
regardless of the airflow setting.
i If you activate the residual heat function
at high temperatures, only the ventilation
will be activated. The blower runs at
medium speed.
XTurn the SmartKey to position 0 in the
ignition lock or remove it.XTo activate: press the Á button.
The indicator lamp in the Á button lights
up.XTo switch off: press the Á button.
The indicator lamp in the Á button goes
out.21 Vehicles with automatic climate control140Operating the climate control systemClimate control

iResidual heat is deactivated
automatically:
R after about 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R if the coolant temperature is too low
Setting the air vents
Important safety notes
GWARNING
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
could cause burns or frostbite to unprotected
skin in the immediate area of the air vents.
Always keep sufficient distance between
unprotected parts of the body and the air
vents. If necessary, use the air distribution
adjustment to direct the air to air vents in the
vehicle interior that are not in the immediate
area of unprotected skin.
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 intake grille on the hood free
of blockages, such as ice, snow or leaves
R never cover the air vents or air intake grille
in the vehicle interior.
i For virtually draft-free ventilation, adjust
the sliders of the air vents to the center
position.
Setting the center air vents:Center air vent, left;Center air vent, right=Center vent thumbwheel, right?Center vent thumbwheel, leftXTo open/close: turn thumbwheels =
and ? up or down.
Setting the side air vents
XTo open/close: turn thumbwheel = up or
down.
i Side window defroster vent : is never
completely shut, even if side air vent ; is
shut.
Setting the air vents141Climate controlZ

Setting the rear-compartment air
vents
Setting the center vents in the rear
compartment:Rear control panel 22;Rear-compartment air vent, right=Rear-compartment air vent, left
When the climate control panel is switched
on/off, the air supply through the rear-
compartment air vents is also switched on/
off.
Setting the B-pillar air vents
:B-pillar air vent;Thumbwheel for B-pillar air ventXTo open/close: turn thumbwheel ; to the
left or right.
Side air vents in the rear compartment (third row
of seats)
:Defroster vent;B-pillar air vent=Thumbwheel for B-pillar air ventXTo open/close: turn thumbwheel = up or
down.22 Vehicles with automatic climate control.142Setting the air ventsClimate control