2012 MERCEDES-BENZ B-CLASS clock setting

You can reach the emergency release via the
cargo compartment. Fold the rear backrests
forward (
Y page 240).
X Take the mechanical key out of the
SmartKey (Y page 69). X
Insert mechanical key ; into the opening
in paneling :.
X Turn mechanical key ; 90° clockwise.
X Push mechanical key ; in the
direction of
the arrow and open the tailgate. Side windows
Important safety notes
G
WARNING
While opening the side windows, body parts
in the closing area could become trapped.
There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
somebody becomes trapped, release the
switch or press the switch to open the side
window again. G
WARNING
If children operate the side windows they
could become trapped,

particularly if they are
left unsupervised. There is a risk of injury.
Activate the override feature for the rear side
windows. When leaving the vehicle, always
take the SmartKey with you and lock the
vehicle. Never leave children unsupervised in
the vehicle. Side window reversing feature
The side windows are equipped with an
automatic reversing feature. If a solid object
blocks or restricts a side window during the
closing process, the

side window opens again
automatically. However, the automatic
reversing feature is only an aid and does not
relieve you of the responsibility of paying
attention when closing a side window. G
WARNING
The reversing feature does not react:
R to soft, light and thin objects, e.g. small
fingers
R over the last

4 mm of the closing movement
R during resetting
R when closing the side window again
manually immediately after automatic
reversing
This means that the reversing feature cannot
prevent someone being trapped in these
situations. There is a risk of injury.
Make sure that no body parts are in close
proximity during the closing procedure. If
someone becomes trapped, press the switch
to open the side window again. Opening and closing the side
windows
The switches for

all side windows are located
on the driver's door. There is also a switch on
each door for the corresponding side window.
The switches on the driver's door take
precedence. Side windows
77
Opening and closing Z
ProCarManuals.com

?
To activate/deactivate air-recirculation mode ( Y page 129)
A To set the airflow ( Y page 126)
B To switch cooling with air dehumidification on/off ( Y page 123)
C To switch the rear window defroster on/off (Y page 128) Notes on using automatic climate
control
Automatic climate control The following contains notes and
recommendations on optimum use of the
automatic climate control.
R
Switch on the air-conditioning system by
turning control knob A clockwise to the
desired position (except position 0).
R Set the temperature to 72 ‡ (22 †).
R Recommendation for preventing
fogged up windows with low outside
temperatures
or rain: switch ¯ on for
the air distribution and switch P and
O off if possible (Y page 126).
In air-recirculation mode, switch d off
(Y page 129).
Set airflow control A to a setting between
3 and 6(Y page 126).
R Recommendation for rapid cooling or
heating of the vehicle interior: briefly set
airflow control A to a setting between 3
and 6(Y page 126).
R Recommendation for a constant
vehicle interior temperature: set airflow
control A to a setting between 1 and
3(Y page 126).
R Recommendation for air distribution in
the winter: set O and
¯(Y page 126).
Recommendation for air distribution in
the summer: set P or P and
¯(Y page 126).
R Only use the "windshield defrosting"
function 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
otherwise 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 three seconds at the bottom of
the screen in the COMAND display. See
also the separate COMAND operating
instructions 4
. You will see the current
settings of the various climate control
functions.
ECO start/stop function During automatic engine switch-off, the ECO
start/stop function only operates at a
reduced capacity. If you require the full
climate control
output,

you can switch off the
ECO start/stop function by pressing the ECO
button ( Y page 138).
4 Only for vehicles with "COMAND Multimedia System" optional equipment120
Overview of climate control systemsClimate control
ProCarManuals.com

for the front-passenger side as well. The
indicator lamp
in
the á button goes out.
R Use 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 deactivated with the ignition switched
off.
ECO start/stop function During automatic engine switch-off, the ECO
start/stop function only operates at a
reduced capacity. If you require the full
climate control
output,

you can switch off the
ECO start/stop function by pressing the ECO
button ( Y page 138). Operating the climate control
systems
Switching climate control on/off
Points to observe before use 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 only
briefly
Activating/deactivating
Automatic climate control
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To switch on: turn control A
clockwise to
the desired position (except position 0)
(Y page 119).
X To switch off: turn control A counter-
clockwise to position 0(Y page 119). Dual-zone automatic climate control
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To activate: press the à button.
The indicator
lamp

in the à button 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 are
restored.
X To deactivate: press the ^ button.
The indicator lamp

in the ^ button lights
up.
i Dual-zone automatic climate control:
switch on climate control primarily using
the à button. Activating/deactivating cooling with
air dehumidification
Points to observe before use If you deactivate the "Cooling with air-
dehumidification" function, the air inside the
vehicle will not be cooled. The air inside the
vehicle will also not be dehumidified. The
windows can
fog

up more quickly. Therefore,
only deactivate the "Cooling with air-
dehumidification" function briefly.
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.
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 systems
123
Climate control
ProCarManuals.com

Problems with the "Cooling with air dehumidification" function
Problem Possible causes/consequences and
M SolutionsThe indicator lamp in
the ¿ button
flashes three times or
remains off. The
"Cooling with air
dehumidification"
function cannot be
switched on. Cooling with air dehumidification has been deactivated due to a
malfunction.
X
Visit a qualified specialist workshop. Setting the climate control to
automatic
The automatic function is only available in
conjunction with dual-zone
automatic climate
control.
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.
The automatic mode functions optimally
when the "Cooling with air dehumidification"
function is activated. If necessary, cooling
with air dehumidification can be deactivated.
If you deactivate the "Cooling with air-
dehumidification" function, the air inside the
vehicle will not be cooled. The air inside the
vehicle will also not be dehumidified. The
windows can fog up more quickly. Therefore,
only deactivate the "Cooling with air-
dehumidification" function briefly.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Set the desired temperature.
X To activate: press the à button.
The indicator lamp

in the à button lights
up. Automatic air distribution and airflow
are activated. X
To switch to manual mode: press the
É or Ë button.
or
X Press the K or I button.
The indicator lamp

in the à button goes
out. Automatic air distribution and airflow
are deactivated. Setting the temperature
Automatic climate control You can set the temperature for the entire
vehicle.
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To increase/reduce: turn control :
clockwise or counter-clockwise
(Y page 119).

Only change the temperature
setting in small increments. Start at 72 ‡
(22 †).
Dual-zone automatic climate control Different temperatures can be set for the
driver's and front-passenger sides.
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To increase/reduce: turn control : or
E clockwise or counter-clockwise
(Y page
121).

Only change the temperature Operating the climate control systems
125
Climate control
ProCarManuals.com

setting in small increments. Start at 72 ‡
(22 †).
Setting the air distribution
Automatic climate control Air distribution settings
¯
Directs air through the defroster vents
P Directs air through the center and side
air vents
O Directs air through the footwell air
vents
i You can also activate several air
distribution settings simultaneously. To do
this, press multiple
air distribution buttons.
The air is then directed through various
vents.
Setting the air distribution
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Press one or more of the P, O,
¯ buttons.
The corresponding indicator

lamp lights up
briefly.
Dual-zone automatic climate control Air distribution settings
¯
Directs air through the defroster vents
P Directs air through the center and side
air vents
O Directs air through the footwell air
vents
b Directs air through the defroster,
center and side air vents
a Directs air through the defroster and
footwell vents
i Regardless of the air distribution setting,
airflow is always directed through the side
air vents. The side air vents can only be
closed if the

adjusters are turned clockwise
until they engage. Setting the air distribution
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Press the É or Ë button repeatedly
until the desired symbol appears in the
display. Setting the airflow
Automatic climate control X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To increase/reduce: turn control A
clockwise or counter-clockwise
(Y page 119).
Dual-zone automatic climate control X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To increase/reduce: press the K or
I button. Switching the ZONE function on/off
This function is only available with dual-zone
automatic climate control.
X To activate: press the á button.
The indicator lamp

in the á button lights
up.
The temperature setting for the driver's
side is not adopted for the front-passenger
side.
X To deactivate: press the á button.
The indicator lamp

in the á button goes
out.
The temperature setting for the driver's
side is adopted for the front-passenger
side. 126
Operating the climate control systems
Climate control
ProCarManuals.com

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 "windshield
defrosting" function until the windshield is
clear again.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 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
i The "windshield defrosting" function
automatically sets the

blower output to the
optimum defrosting effect. As a result, the
airflow may increase or decrease
automatically after the button is pressed.
i You can adjust the blower output
manually while the "Windshield defrosting"
function is in operation:
R Automatic climate control: turn airflow
control A clockwise or counter-
clockwise (Y page 119).
R Dual-zone automatic climate control:
press the ó or ô 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
Press the à button. 5
The indicator
lamp

in the ¬ button goes
out. Airflow and air distribution are set to
automatic mode.
or
X Automatic climate control: turn
temperature control : clockwise or
counter-clockwise ( Y page 119).
Dual-zone automatic climate control:
turn temperature controls : or E
clockwise or counter-clockwise
(Y page 121). MAX COOL maximum cooling
The MAX COOL function is only available in
vehicles for the USA.
MAX COOL is only operational when the
engine is running.
X To activate: press the Ù button.
The indicator lamp in the button lights up.
X To deactivate: press the Ù button
again.
The indicator lamp

goes out. The previously
selected settings are restored.
When you activate MAX COOL, climate
control switches to the following functions:
R maximum cooling
R maximum airflow
R air-recirculation mode on Defrosting the windows
Windows fogged up on the inside Automatic climate control
X
Activate the ¿ "Cooling with air
dehumidification" function.
X If the windows continue to fog up, activate
the "windshield defrosting" function
(Y page 127).
5 3-zone automatic climate control only. Operating the climate control systems
127Climate control
ProCarManuals.com

X
Turn the SmartKey to position 0 in the
ignition lock or remove it ( Y page 135).
X To activate: press the Ì button.
The indicator lamp
in the Ì button lights
up.
X To deactivate: press the Ì button.
The indicator lamp

in the Ì button goes
out.
i Residual heat is deactivated
automatically:
R after approximately 30 minutes
R when the ignition is switched on
R if the battery voltage drops
R when the auxiliary heating is activated Setting the air vents
Important safety notes
G
WARNING
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
outlets. 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.
i You can move the adjusters for the air
vents vertically or horizontally to set the
direction of the airflow.
i For 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 vent: turn the
adjuster in one of center air vents :
counter-clockwise.
X To close the center air vent: turn the
adjuster in one of center air vents :
clockwise until it engages. 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 ; counter-clockwise.
X To close a side air vent: turn the
adjuster
in side air vent ; clockwise until it
engages. 130
Setting the air vents
Climate control
ProCarManuals.com