climate control MERCEDES-BENZ B-CLASS 2012 Owner's Manual

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
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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
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Climate control Z
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X
Push a round pen into opening
=(Y page 263) for approximately three
seconds.
The zone currently selected appears in
compass display ;(Y page 263).
X To select the zone: push
a round pen into
opening =(Y page 263) until the desired
zone is selected.
If, after a few seconds, the display in
compass display ;(Y page 263) changes
direction, the zone has been selected.
Calibrating the compass X
Make sure that there is sufficient space for
you to drive in a circle without impeding
traffic.
In order to calibrate the compass correctly,
do the following:
R calibrate the compass in the open and not
in the vicinity of steel structures or high-
voltage transmission lines.
R switch off electrical

consumers such as the
climate control, windshield wipers or rear
window defroster.
R close all doors and the tailgate.
X Switch on the ignition.
X Push a round pen into opening
=(Y page 263) for approximately six
seconds, until symbol C is shown in
compass display ;(Y page 263).
X Drive your vehicle in a full circle at
approximately 3 mph (5 km/h) to 6 mph
(10 km/h

).
When the calibration has successfully been
completed, the current direction is shown
in compass display ;(Y page 263).Floormat on the driver's side
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. X
Slide the seat backwards.
X To install: place the floormat in the
footwell.
X Press safety catch knobs : onto
retainers ;.
X To remove: pull the floormat off
retainers ;.
X Remove the floormat.264
Features
Stowage and features
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Uniform Tire Quality Grading
Standards
Overview of Tire Quality Grading
Standards
Uniform Tire Quality Grading Standards are
U.S. government specifications. Their
purpose is to provide drivers with uniform
reliable information
on
tire performance data.
Tire manufacturers have to grade tires using
three performance factors: tread wear :,
tire traction ;, and heat resistance =.
These regulations do not apply to Canada.
Nevertheless, all tires sold in North America
are provided with the corresponding quality
grading markings on the sidewall of the tire.
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
For example: Treadwear Traction Temperature
200 AA A Treadwear
The treadwear grade is a comparative rating
based on the

wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from
the norm, due to variations in driving habits,
service practices and differences in road
characteristics and climate conditions. Traction
G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.
The traction grades, from highest to lowest,
are AA, A, B, and C. Those grades represent
the tire's ability to stop on a wet surface as
measured under controlled conditions on
specified government test

surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance.
The safe speed on a wet, snow covered or icy
road is always lower than on dry road
surfaces.
You should pay special attention to road
conditions when temperatures are around
the freezing point.
Mercedes-Benz recommends a minimum
tread depth of ã in (4 mm) for all four winter
tires ( Y page 300) to maintain normal driving
characteristics in winter. Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
Stopping distance, however, is still
considerably greater than when the road is Uniform Tire Quality Grading Standards
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Wheels and tires Z
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applicable to your vehicle on the vehicle
identification plate.
VIN
X
Slide the right-hand front seat to its
rearmost position.
X Fold up floor covering : in front of the
right-hand front seat.
You will see VIN ;.
The VIN can also be found in the following
locations:
R on the lower edge of the windshield
(Y page 329)
R on the vehicle identification plate
(Y page 328) Engine number
:
Emissions control information plate
; Engine number (stamped into the
crankcase)
= VIN (on the lower edge of the windshield) Service products and filling
capacities
Important safety notes
G
WARNING
Service products may be poisonous and
hazardous to health. There is a risk of injury.
Comply with instructions on the use, storage
and disposal of
service products on the labels
of the respective original containers. Always
store service products sealed in their original
containers. Always keep service products out
of the reach of children. H
Environmental note
Dispose of service products in an
environmentally responsible manner.
Service products include the following:
R Fuels
R Lubricants (e.g. engine

oil, transmission oil)
R Coolant
R Brake fluid
R Windshield washer fluid
R Climate control system refrigerant
Components and service products must be
matched. You should therefore only use
products that have been tested and approved
by Mercedes-Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz. Service products and filling capacities
329
Technical data Z
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i
Use antifreeze/corrosion inhibitor
according to MB approval 325.0 or 326.0. Windshield washer system and
headlamp cleaning system
Important safety notes G
WARNING
Windshield washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windshield washer
concentrate is spilled next to the filler neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not add
distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
When handling washer fluid, observe the
important safety notes on service products
(Y page 329).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture
of water and windshield washer fluid, e.g.
MB SummerFit.
Add 1 part MB SummerFit to 100 parts water. At temperatures below freezing:
X
Fill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB
WinterFit.
Adapt the mixing ratio to the outside
temperature.
R Down to 14 ‡ (Ò

10 †): mix 1 part MB
WinterFit with 2 parts water.
R Down to Ò4 ‡ (Ò20 †): mix 1 part MB
WinterFit with 1 part water.
R Down to Ò20.2 ‡ (Ò29 †): mix 2 parts MB
WinterFit with 1 part water.
i Add windshield washer fluid, e.g. MB
SummerFit or MB WinterFit, to the washer
fluid all year round. Climate control system refrigerant
Important safety notes Type of refrigerant
The instruction label about types of
refrigerants can be found on the radiator
cross member.
Refrigerant R-134a
!
Only use refrigerant R-134a and PAG oil
(part number A0019890803) which has
been approved by Mercedes-Benz. The
approved R-134a PAG

oil may not be mixed
with other conventional PAG oils.
Otherwise, the climate control system may
be damaged.
Service work, such as topping-up refrigerant
or replacing components, may only be carried
out by a qualified specialist workshop. All
applicable regulations must be adhered to,
SAE standard J639 included.
Always have work on the climate control
system carried out at a qualified specialist
workshop. 334
Service products and filling capacitiesTechnical data
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