2012 MERCEDES-BENZ B-CLASS Owners Manual

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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Problems with the rear window defroster
Problem Possible causes/consequences and
M SolutionsThe rear window
defroster has
deactivated
prematurely or cannot
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-
recirculation mode
If you switch on air-recirculation mode, the
windows can fog up more quickly, in
particular at low temperatures. Only use air-
recirculation mode briefly to prevent the
windows from fogging up.
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.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 135).
X To activate: press the e button.
The indicator lamp

in the e 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 e button is not lit.
Outside air is added after about
30 minutes.
X To deactivate: press the e button.
The indicator lamp

in the e button goes
out. i
Air-recirculation mode deactivates
automatically:
R after approximately five minutes at
outside temperatures below
approximately 41 ‡ (5 †)
R after approximately five minutes if the
"Cooling with air dehumidification"
function is deactivated
R after approximately 30 minutes at
outside temperatures above
approximately

41 ‡(5 †) if the "Cooling
with air dehumidification" function is
activated Activating/deactivating the residual
heat function
The residual heat

function is only available in
vehicles for Canada 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 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. Operating the climate control systems
129
Climate control
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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
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Setting the rear-compartment air
vents
:
Rear-compartment air vent, left
; Rear-compartment air vent, right
= Rear-compartment air vent thumbwheel
X To open/close: turn thumbwheel
= up or
down. Setting the air vents
131
Climate control Z
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132ProCarManuals.com

Useful information ............................
134
Notes on breaking-in a new vehicle 134 Driving ............................................... 134
Automatic transmission ...................140
Refueling ............................................ 147
Parking
............................................... 149
Driving tips ........................................ 152
Driving systems ................................ 157 133
Driving and parking
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Notes on breaking-in a new vehicle
Important safety notes
New and replaced brake pads and discs only
reach their optimum braking effect after
several hundred kilometers of driving.
Compensate for this

by applying greater force
to the brake pedal. The first 1,000miles (1,500 km)
The more you

look after the engine when it is
new, the more satisfied you will be with its
performance in the future.
R You should therefore drive at varying
vehicle and engine speeds for the first
1,000 miles (1,500 km).
R Avoid heavy loads, e.g. driving at full
throttle, during this period.
R Change gear in good time, before the
tachometer needle is Ô of the way to the
red area of the tachometer.
R Do not manually shift to a lower gear to
brake the vehicle.
R If possible, do not depress the accelerator
pedal past the point of resistance
(kickdown).
R Ideally, for the first 1,000 miles (1,500 km),
drive in program E. After 1,000 miles (1,500km), you can
increase the
engine

speed gradually and bring
the vehicle up to full speed.
i You should also observe these notes on
breaking-in if the engine or parts of the
drive train on your vehicle have been
replaced.
i Always observe the respective speed
limits. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell can restrict the
pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle
is jeopardized. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Install the floormats
securely and as specified in order to ensure
sufficient clearance for

the pedals. Do not use
loose floormats. G
WARNING
Unsuitable footwear can hinder correct usage
of the pedals, e.g.:
R shoes with thick soles
R shoes with high heels
R slippers
There is a risk of an accident.
Wear suitable footwear to ensure correct
usage of the pedals. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or

not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident. 134
Driving
Driving and parking
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