2012 MERCEDES-BENZ B-CLASS ESP

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
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Wheels and tires
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Checking tire pressures manually
To determine and set the correct tire
pressure, proceed as follows:
X
Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard on the
B-pillar on the
driver's side of your vehicle.
X If necessary, increase the tire pressure to
the recommended value ( Y page 301).
X If the tire pressure is too high, release air
by pressing down

the metal pin in the valve
using the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
Important safety notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set
tire
pressure

using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multifunction
display.
The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure ( Y page 301).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since an even loss of
pressure on several tires at the same time
cannot be detected by the tire pressure loss
warning system. The tire pressure loss warning system is not
able to
warn

you of a sudden loss of pressure,
e.g. if the tire is penetrated by a foreign
object. In the event of a sudden loss of
pressure, bring the vehicle to a halt by braking
carefully. Avoid abrupt steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted to your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss
warning system Restart the tire pressure loss warning system
if you have:
R
changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found in the table on the fuel filler flap.
The tire pressure loss warning system can
only give reliable warnings if you have set
the correct tire

pressure. If an incorrect tire
pressure is set, these incorrect values will
be monitored.
X Observe the notes on tire pressure
(Y page 301).
X Make sure that the SmartKey is in
position 2 (Y page 135)

in the ignition lock. Tire pressure
305
Wheels and tires Z
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X
Press = or ; on the steering wheel
to select the Service menu.
X Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The Run Flat Indicator Active
Press 'OK' to Restart message
appears in the multifunction display.
If you wish to confirm the restart:
X Press the a button.
The Tire Pressure Now OK? message
appears in the multifunction display.
X Press the 9 or : button to select
Yes.
X Press the a button.
The Run Flat Indicator Restarted
message appears in the multifunction
display.
After a teach-in period, the tire pressure
loss warning system will monitor the set
tire pressures of all four tires.
or
If you wish to cancel the restart:
X Press the % button.
or
X If the Tire Pressure Now OK? message
appears, use the 9 or : button to
select Cancel.
X Press the a button.
The tire pressure values stored at the last
restart will continue to be monitored. Loading the vehicle
Instruction labels for tires and loads
G
WARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires
can also impair the
steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of your vehicle. Never overload the tires by
exceeding the maximum load.
:
B-pillar, driver's side
Two instruction labels on your vehicle show
the maximum possible load.
(1) The Tire and Loading Information placard is on the

B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight

rating. It is made up
of the vehicle weight, all vehicle
occupants, the fuel and the cargo. You
can also find information about the
maximum gross axle weight rating on the
front and rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the
maximum gross axle weight rating for the
front or rear axle. 306
Loading the vehicleWheels and tires
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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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not covered with ice or snow. Take
appropriate care when driving.
!
Avoid wheelspin. This
can lead to damage
to the drive train. Temperature
G
WARNING
The temperature grade for this tire is
established for a tire that is properly inflated
and not overloaded. Excessive speed,
underinflation, or excessive loading, either
separately or in combination, can cause
excessive heat build-up and possible tire
failure.
The temperature grades are A (the highest),
B, and C. These represent the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause

the material of the tire
to degenerate and reduce tire life, and
excessive temperature can lead to sudden
tire failure. The grade C corresponds to a level
of performance which all passenger car tires
must meet under the Federal Motor Vehicle
Safety Standard No. 109. Grades B and A
represent higher levels of performance on the
laboratory test wheel than the minimum
required by law. Tire labeling
Overview of tire labeling
The following markings are on the tire in addition
to the tire name (sales designation) and the
manufacturer's name:
:
Uniform tire Quality Grading Standard
(Y page 316)
; DOT, Tire Identification Number
(Y page 315)
= Maximum tire load ( Y page 310)
? Maximum tire pressure (Y page 304)
A Manufacturer
B Tire material ( Y page 316)
C Tire size designation, load-bearing
capacity and speed index (
Y page 313)
D Load index ( Y

page 315)
E Tire name
i Tire data is vehicle-specific and may
deviate from the data in the example. 312
Tire labeling
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adapt your driving style to the traffic
conditions.
Summer tires
Index Speed rating
Q up to 100mph (160 km/h)
R up to 106mph (170 km/h)
S up to 112mph (180 km/h)
T up to 118mph (190 km/h)
H up to 130mph (210 km/h)
V up to 149mph (240 km/h)
W up to 168mph (270 km/h)
Y up to 186mph (300 km/h)
ZR...Y up to 186mph (300 km/h)
ZR...(..Y) over 186mph (300 km/h)
ZR over 149mph (240 km/h)
R
Optionally, tires with a maximum speed of
over 149 mph
(240km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR 18).
The service specifications consist of load
bearing index A and speed rating B.
R If the size description of your tire includes
"ZR" and there are no service
specifications, ask the tire manufacturer in
order to find out the maximum speed.
If a service specification is available, the
maximum speed is limited according to the
speed rating in the service specification.
Example: 245/40 ZR 18 97 Y. In this
example, "97 Y" is the service specification.
The letter "Y" represents the speed rating
and the maximum speed of the tire is
limited to 186 mph (300km/h).
R The size description for all tires with
maximum speeds of over 186mph
(300km/h) must include "ZR", and theservice specification must be given in
brackets. Example:
275/40 ZR 18 (99 Y).
The speed rating "(Y)" indicates that the
maximum speed

of the tire is over 186mph
(300km/h). Ask the tire manufacturer
about the maximum speed. All-weather tires and winter tires
Index Speed rating
Q M+S
6 up to 100mph (160 km/h)
T M+S
6 up to 118mph (190 km/h)
H M+S
6 up to 130mph (210 km/h)
V M+S
6 up to 149mph (240 km/h)
i
Not all tires

with the M+S marking provide
the driving characteristics of winter tires.
Winter tires have, in addition to the M+S
identification, the i snow flake symbol
on the tire sidewall. Tires with this marking
fulfill the requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC)
regarding the tire traction on snow. They
have been especially developed for driving
on snow.
An electronic speed limiter prevents your
vehicle from exceeding a speed of 130mph
(210km/h).
The speed rating of tires mounted at the
factory may be higher than the maximum
speed that the electronic speed limiter
permits.
Make sure that your tires have the required
speed rating, e.g. when buying new tires. The
required speed rating for your vehicle can be
found in the "Tires" section ( Y page 323).
Further information about reading tire data
can be obtained from any qualified specialist
workshop.
6 Or M+S i for winter tires.314
Tire labeling
Wheels and tires
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GAWR (Gross Axle Weight Rating)
The GAWR is
the maximum gross axle weight
rating. The actual load on an axle must never
exceed the gross axle weight rating. The
gross axle weight rating can be found on the
vehicle identification plate on the B-pillar on
the driver's side. Speed rating
The speed rating is part of the tire
identification. It specifies

the speed range for
which the tire is approved. GVW (Gross Vehicle Weight)
The gross vehicle weight includes the weight
of the vehicle including fuel, tools, the spare
wheel, accessories installed, occupants,
luggage and the drawbar noseweight, if
applicable. The gross

vehicle weight must not
exceed the gross vehicle weight rating GVWR
as specified on the vehicle identification plate
on the B-pillar on the driver's side. GVWR (Gross Vehicle Weight Rating)
The GVWR is

the maximum permissible gross
weight of a fully loaded vehicle (the weight of
the vehicle including all accessories,
occupants, fuel, luggage and the drawbar
noseweight, if applicable). The gross vehicle
weight rating is specified on the vehicle
identification plate on the B-pillar on the
driver's side. Maximum loaded vehicle weight
The maximum weight is the sum of:
R the curb weight of the vehicle
R the weight of the accessories
R the load limit
R the weight of the factory installed optional
equipment Kilopascal (kPa)
Metric unit for tire pressure. 6.9 kPa
corresponds to 1 psi. Another unit for tire
pressure is bar. 100 kilopascal (kPa) is the
equivalent of 1 bar . Load index
In addition to

the load-bearing index, the load
index may also be imprinted on the sidewall
of the tire. This specifies the load-bearing
capacity more precisely. Curb weight
The weight of a vehicle with standard
equipment including the maximum capacity
of fuel, oil

and coolant. It also includes the air-
conditioning system and optional equipment
if these are installed in the vehicle, but does
not include passengers or luggage. Maximum load rating
The maximum load rating in kilograms or
pounds is the maximum weight for which a
tire is approved. Maximum permissible tire pressure
Maximum permissible tire pressure for one
tire. Maximum load on one tire
Maximum load on one tire. This is calculated
by dividing the

maximum axle load of one axle
by two. PSI (pounds per square inch)
A standard unit of measure for tire pressure. Definition of terms for tires and loading
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X
Turn ratchet wrench ? until jack = sits
completely on jacking point ; and the
base of the jack lies evenly on the ground.
X Turn ratchet wrench ? until the tire is
raised a
maximum
of 1.2 in (3 cm) from the
ground.
Removing a wheel !
Do not place wheel bolts in sand or on a
dirty surface. The bolt and wheel hub
threads could otherwise

be damaged when
you screw them in.
X Unscrew the wheel bolts.
X Remove the wheel.
Mounting a new wheel G
WARNING
Oiled or greased wheel bolts or damaged
wheel bolts/hub threads

can cause the wheel
bolts to come loose. As a result, you could
lose a wheel while driving. There is a risk of
accident.
Never oil or grease wheel bolts. In the event
of damage to the threads, contact a qualified
specialist workshop immediately. Have the
damaged wheel bolts or hub threads
replaced/renewed. Do not continue driving. G
WARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is a risk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
Always pay attention to the instructions and
safety notes in the "Changing a wheel"
section ( Y page 319).
Only use wheel

bolts that have been designed
for the wheel and the vehicle. For safety
reasons, Mercedes-Benz recommends that
you only use wheel bolts which have been
approved for Mercedes-Benz vehicles and the
respective wheel. !
To prevent damage

to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt. X
Clean the wheel and wheel hub contact
surfaces.
X Place the new wheel on the wheel hub and
push it on.
X Tighten the wheel bolts until they are
finger-tight.
Lowering the vehicle G
WARNING
The wheels could work loose if the wheel nuts
and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed. 322
Changing a wheel
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