2012 MERCEDES-BENZ B-CLASS Owners Manual

X
Open the hood.
X Use a dry cloth to remove any moisture
from the fuse box.
X To open: open clamps ;.
X Fold up cover : in the direction of the
arrow and remove it. X
To close: check whether the seal is seated
correctly in cover :.
X Insert cover :
at the back into openings
= on the fuse box.
X Fold down cover :.
X Hook clamps ; into the fuse box and
close.
X Close the hood. Fuse box in the front-passenger
footwell
X
To open: remove the floormat from the
front-passenger side.
X Fold out perforated floor covering :
in the
direction of the arrow. X
To release cover =, press retaining
clamp ;.
X Fold out cover = in the direction of the
arrow to the catch.
X Remove cover = forwards.
i Fuse allocation
chart ?

is located on the
lower right-hand side of cover =.
X To close: insert cover = on the left-hand
side of the fuse box into the retainer.
Cover = engages in the retainers.
X Fold down cover = until clamps ; lock
audibly.
X Fold back perforated floor covering :. Fuses
295
Breakdown assistance Z
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296ProCarManuals.com

Useful information ............................
298
Important safety notes ....................298
Operation ........................................... 298
Winter operation ............................... 300
Tire pressure ..................................... 301
Loading the vehicle ..........................306
Maximum load rating .......................310
Uniform Tire Quality Grading
Standards .......................................... 311
Tire labeling ....................................... 312
Definition of terms for tires and
loading ............................................... 316
Changing a wheel ............................. 319
Wheel and tire combinations ...........323
Emergency spare wheel ...................325 297Wheels and tires
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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).Important safety notes
G
WARNING
If wheels and tires of the wrong size are used,
the wheel brakes or suspension components
may be damaged. There is a risk of an
accident.
Always replace wheels and tires with those
that fulfill the specifications of the original
part.
When replacing wheels,

make sure to use the
correct:
R designation
R model
When replacing tires, make sure to use the
correct:
R designation
R manufacturer
R model G
WARNING
A flat tire severely impairs the driving,
steering and braking characteristics of the
vehicle. There is a risk of accident.
Tires without run-flat characteristics:
R do not drive with a flat tire.
R immediately replace the flat tire with your
emergency spare wheel or spare wheel, or
consult a qualified specialist workshop. Tires with run-flat characteristics:
R
pay attention to the information and
warning notices on

MOExtended tires (tires
with run-flat characteristics).
Accessories that are not approved for your
vehicle by Mercedes-Benz or are not being
used correctly can impair the operating
safety.
Before purchasing and using non-approved
accessories, visit a qualified specialist
workshop and inquire about:
R suitability
R legal stipulations
R factory recommendations
Information on dimensions and types of
wheels and tires for your vehicle can be found
(Y page 323).
Information on air pressure for the tires on
your vehicle can be found:
R on the vehicle's Tire and Loading
Information placard on the B-pillar
R on the tire pressure label on the fuel filler
flap
R under "Tire pressure"
i Further information on wheels and tires
can be obtained at any qualified specialist
workshop. Operation
Information on driving
R If the vehicle is heavily loaded, check the
tire pressures and correct them if
necessary.
R While driving, pay attention to vibrations,
noises and unusual handling
characteristics, e.g. pulling to one side.
This may indicate that the wheels or tires
are damaged. If you suspect that a tire is
defective, reduce your speed immediately.
Stop the vehicle as soon as possible to
check the wheels and tires for damage.
Hidden tire damage could also be causing298
Operation
Wheels and tires
ProCarManuals.com

the unusual handling characteristics. If you
find no signs of damage, have the wheels
and tires checked at a qualified specialist
workshop.
R When parking your
vehicle, make sure that
the tires do not get deformed by the curb
or other obstacles. If it is necessary to drive
over curbs, speed humps or similar
elevations, try to do so slowly and at an
obtuse angle. Otherwise, the tires,
particularly the sidewalls, may be
damaged. Regular checking of wheels and tires
G
WARNING
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle. There is a risk of
accident.
Check the tires regularly for signs of damage
and replace any damaged tires immediately.
Regularly check the wheels and tires of your
vehicle for damage

at least once a month, as
well as after driving off-road or on rough
roads. Damaged wheels can cause a loss of
tire pressure. Pay particular attention to
damage such as:
R cuts in the tires
R punctures
R tears in the tires
R bulges on tires
R deformation or severe corrosion on wheels
Regularly check the tire tread depth and the
condition of the tread across the whole width
of the tire (Y page 299). If necessary, turn
the front wheels to full lock in order to inspect
the inner side of the tire surface.
All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
mount anything onto the valve other than the
standard valve cap or other valve caps
approved by Mercedes-Benz for your vehicle. Do not use any other valve caps or systems,
e.g. tire pressure monitoring systems.
Regularly check the pressure of all the tires
particularly prior
to

long trips. Adjust the tire
pressure as necessary ( Y page 301).
The service life of tires depends, among other
things, on the following factors:
R Driving style
R Tire pressure
R Distance covered Tire tread
G
WARNING
Insufficient tire tread will reduce tire traction.
The tire is no longer able to dissipate water.
This means that

on wet road surfaces, the risk
of hydroplaning increases, in particular where
speed is not adapted to suit the driving
conditions. There is a risk of accident.
If the tire pressure is too high or too low, tires
may exhibit different levels of wear at
different locations on the tire tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tires.
Minimum tire tread depth for:
R Summer tires: â in (3 mm)
R M+S tires: ã in (4 mm)
For safety reasons, replace the tires before
the legally prescribed limit for the minimum
tire tread depth is reached. Operation
299
Wheels and tires Z
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Bar indicator : for tread wear is integrated
into the tire tread.
Treadwear indicators (TWI) are required by
law. Six indicators are positioned on the tire
tread. They are visible once the tread depth
is approximately
á
in (1.6 mm). If this is the
case, the tire is so worn that it must be
replaced. Selecting, mounting and replacing
tires
R Only mount tires and wheels of the same
type and make.
Exception: it is permissible to mount a
different type or

make in the event of a flat
tire. Observe the "MOExtended tires (tires
with run-flat characteristics" section
(Y page 281).
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, break in them in
at moderate speeds for the first 60 miles
(100 km), as they only reach their full
performance after this distance.
R Do not drive with tires which have too little
tread depth, as this significantly reduces
the traction on wet roads (hydroplaning).
R Replace the tires after six years at the
latest, regardless of wear. MOExtended tires (tires with run-flat
properties)
With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires.
MOExtended tires may only be used in
conjunction with an active tire pressure loss
warning system and only on wheels
specifically tested by Mercedes-Benz.
Notes on driving with MOExtended tires with
a flat tire ( Y page 281). i
Vehicles equipped with

MOExtended tires
are not equipped with a TIREFIT kit at the
factory. It is therefore recommended that
you additionally equip your vehicle with a
TIREFIT kit if you mount tires that do not
feature run-flat properties, e.g. winter tires.
A TIREFIT kit can be obtained from a
qualified specialist workshop. Winter operation
General notes
Have your vehicle

winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Changing a wheel"
section ( Y page 319). Driving with summer tires
At temperatures below

45 ‡ (+7 †), summer
tires lose elasticity and therefore traction and
braking power. Change the tires on your
vehicle to M+S tires. Using summer tires at
very cold temperatures could cause cracks to
form, thereby damaging the tires
permanently. Mercedes-Benz cannot accept
responsibility for this type of damage. M+S tires
G
WARNING
M+S tires with a tire tread depth of less than
ã in (4

mm) are not suitable for use in winter
and do not provide sufficient traction. There
is a risk of an accident.
M+S tires with a tread depth of less than ã
in (4 mm) must be replaced immediately.
At temperatures below 45 ‡ (+7 †), use
winter tires or all-season tires. Both types of
tire are identified by the M+S marking.
Only winter tires bearing the i snowflake
symbol in addition to the M+S marking
provide the best possible grip in wintry road
conditions. Only these tires will allow driving 300
Winter operation
Wheels and tires
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safety systems such as ABS and ESP
®
to
function optimally in
winter. These tires have
been developed specifically for driving in
snow.
Use M+S tires of the same make and tread on
all wheels to maintain safe handling
characteristics.
Always observe the maximum permissible
speed specified for the M+S tires you have
mounted.
Once the winter tires are mounted:
X Check the tire pressures (Y page 305).
X Restart the tire pressure loss warning
system (Y page 305).
For more information on driving with the
emergency spare wheel, see ( Y page 325).Snow chains
G
WARNING
If snow chains are mounted on the rear
wheels, the snow

chains could cause abrasion
to the vehicle body or to chassis components.
This could cause damage to the vehicle or the
tires. There is a risk of an accident.
To avoid hazardous situations:
R never mount snow chains on the rear
wheels
R only mount snow chains in pairs on the
front wheels.
! On some tire sizes there is not enough
space for snow chains. To avoid damage to
the vehicle or tires, observe the "Wheel and
tire combinations" section under "Tires and
wheels".
For safety reasons, Mercedes-Benz
recommends that you only use snow chains
that have been specially approved for your
vehicle by Mercedes-Benz, or are of a
corresponding standard of quality. If you intend to mount snow chains, please
bear the following points in mind:
R
Snow chains may not be mounted on all
wheel/tire combinations. Permissible
wheel-tire combinations (Y page 323).
R Only use snow chains when driving on
roads completely covered by snow.
Remove the snow chains as soon as
possible when you come to a road that is
not snow-covered.
R Local regulations may restrict the use of
snow chains. Observe the appropriate
regulations if you wish to mount snow
chains.
R Do not exceed the maximum permissible
speed of 30 mph (50 km/h).
R When snow chains

are installed, never use
Active Parking Assist (Y page 172).
i You may wish to deactivate
ESP ®
(Y page 62) when pulling away with
snow chains installed. You can thereby
allow the wheels to spin in a controlled
manner, achieving an increased driving
force (cutting action).
For more information on driving with the
emergency spare wheel, see ( Y page 325). Tire pressure
Tire pressure specifications
G
WARNING
Tires with tire pressures that are too low or
too high are associated with the following
hazards:
R they can burst,

in particular if the vehicle is
heavily laden or when driven at high
speeds.
R the tires can wear excessively and/or
unevenly, which can severely impair tire
traction.
R the driving, steering and braking
characteristics may be severely impaired.
There is a risk of accident. Tire pressure
301
Wheels and tires
ZProCarManuals.com

Follow recommended tire inflation pressures
and check the pressure of all the tires
including the spare wheel:
R
monthly, at least
R if the load changes
R before beginning a long journey
R under different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit
any reliable conclusion about
the tire pressure. On vehicles equipped with
the electronic tire pressure monitor, the tire
pressure can be checked in the on-board
computer.
The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
1.) Tire and Loading Information placard
on the B-pillar on the driver's side of the
vehicle ( Y page 306).
The Tire and Loading Information placard
contains the recommended

tire pressures for
cold tires. The recommended tire pressures
are valid for the maximum permissible load
and up to the maximum permissible vehicle
speed. :
Recommended tire pressures
Option 2) Tire pressure table on the inside
of the fuel filler flap.
The tire pressure table contains the
recommended pressures for cold tires for various operating conditions, i.e. differing
load and speed conditions.
i
Specifications shown in the examples of
tire pressure tables are for illustration
purposes only. Tire

pressure specifications
are vehicle-specific and may deviate from
the data shown here. Tire pressure
specifications applicable to your vehicle
are located in your vehicle's tire pressure
table. Example: tire pressure table for all tires permitted
for this vehicle by the factory
If a
tire

size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size. The load conditions "partially
laden" and "fully laden" are defined in the
table for different numbers of occupants and
amounts of luggage. The actual number of
seats may differ. Example: tire pressure table with tire dimensions
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18. Rim diameter

is part of the tire size and302
Tire pressure
Wheels and tires
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