2012 MERCEDES-BENZ B-CLASS light

Problems with the windshield wipers
Problem Possible causes/consequences and
M SolutionsThe windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield
wiper movement. The wiper motor has been deactivated.
X
For safety reasons, you should remove the SmartKey from the
ignition lock.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on. The windshield wipers
fail completely. The windshield wiper drive is malfunctioning.
X
Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist
workshop. The spray nozzles are
misaligned. The windshield washer fluid from the spray nozzles no longer hits
the center of the windshield. The spray nozzles are misaligned.
X
Have the spray nozzles adjusted at a qualified specialist
workshop. Windshield wipers
115Lights and windshield wipers Z
ProCarManuals.com

Canada only
:
To set the temperature, left (Y page 125)
; To set climate control to automatic ( Y page 125)
= To defrost the windshield (Y page 127)
? To increase the airflow ( Y page 126)
A To set the air distribution ( Y page 126)
B Display
C To activate/deactivate air-recirculation mode ( Y page 129)
D To switch climate control on/off (Y page 123)
E To set the temperature, right (Y page 125)
F To switch the residual heat function on/off (Y page 129)
G To switch cooling with air dehumidification on/off ( Y page 123)
H To reduce the airflow ( Y page 126)
I To switch the rear window defroster on/off (Y page 128)
J To switch the ZONE function on/off (Y page 126) Notes on using dual-zone automatic
climate control
Automatic climate control The following contains instructions and
recommendations to enable you to get the
most out of your automatic climate control.
R
Activate climate control
using the à and
¿ buttons. The indicator lamps in the
à and ¿ buttons light up.
R Set the temperature to 72 ‡ (22 †). 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 Use the ZONE function to adopt the
temperature settings on the driver's side122
Overview of climate control systems
Climate control
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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
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Activating/deactivating
X
To activate: press the ¿ button.
The indicator lamp
in the ¿ button lights
up.
X To deactivate: press the ¿ button.
The indicator lamp

in the ¿ button goes
out. The "Cooling with air dehumidification"
function has a delayed switch-off feature. 124
Operating the climate control systems
Climate control
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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
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i
You should only select this setting until
the windshield is clear again.
Dual-zone automatic climate control
X Activate the ¿ "Cooling with air
dehumidification" function.
X Activate automatic mode Ã.
X If the windows continue to fog up, activate
the "windshield defrosting" function
(Y page 127).
i You should only select this setting until
the windshield is clear again.
Windows fogged up on the outside X
Activate the windshield wipers.
X Set the air distribution to P or O.
i You should only select this setting until
the windshield is clear again. Rear window defroster
Activating/deactivating 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
automatically after several minutes.
If the battery voltage is too low, the rear
window defroster may switch off.
X
Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X Press the ¤ button.
The indicator lamp
in the ¤ button lights
up or goes out. 128
Operating the climate control systems
Climate control
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