2011 MERCEDES-BENZ C-Class Owner's Manual

Directives to be observed
R Only mount tires and wheels of the same
type and make.
R Only mount tires of the correct size onto
the wheels.
R After mounting new tires, run 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 use tires until they are excessively
worn as the tire traction on wet road
surfaces decreases significantly when the
tread depth is less than 1
/ 8 in (3 mm).
R If the vehicle is heavily laden, check the tire
pressure and adjust it if necessary.
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, can get
damaged.
Maintenance and care of wheels and
tires
Checking wheels and tires
GWarning
Regularly check the tires for damage.
Damaged tires can cause tire inflation
pressure loss. As a result, you could lose
control of your vehicle.
Worn, old tires can cause accidents. If the tire
tread is worn to minimum tread depth, or if
the tires have sustained damage, replace
them.
R Regularly check the wheels and tires of
your vehicle for damage (e.g. cuts,
punctures, tears, bulges on tires and
deformation or cracks or severe corrosion
on wheels), 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.
R Regularly check the tire tread depth and
the condition of the tread across the whole
width of the tire (Y page 271). If necessary,
turn the front wheels to full lock in order to
inspect the inner side of the tire surface.
R All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not
install anything on the valve (such as tire
pressure monitoring systems) other than
the standard valve cap or other valve caps
approved by Mercedes-Benz for your
vehicle.
R Regularly check the pressure of all the tires
including the emergency spare wheel or the
spare wheel, particularly prior to long trips,
and correct the pressure as necessary
( Y page 272).
Service life of tires
The service life of tires depends on the
following factors amongst other things:
R driving style
R tire pressure
R mileage
Replace the tires after six years at the latest,
regardless of wear. This also applies to the
emergency spare wheel/spare wheel.
Tire tread
GWarning
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the tread wear indicators (TWI) become
visible at approximately 1
/ 16 in (1.6 mm), we
recommend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1
/ 8 in (3 mm), the adhesion
properties on a wet road are sharply reduced.
Maintenance and care of wheels and tires271Tires and wheelsBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 271Z

Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not use tires until they are excessively
worn as the tire traction on wet road surfaces
decreases significantly when the tread depth
is less than 1
/ 8 in (3 mm).
Tread wear indicators (TWI) are required by
law. Six indicators are positioned over the tire
tread. They are visible as soon as a tread
depth of approximately 1
/ 16 in (1.6 mm) is
reached. If this is the case, the tire is so worn
that it must be replaced.
The recommended tread depth for summer
tires is at least 1
/ 8 in (3 mm). The
recommended tread depth for winter tires is
at least 1
/ 6 in (4 mm).
Bar marking
: for tread wear is integrated
into the tire tread.
Storing tires
Store tires that are not being used in a cool,
dry and preferably dark place. Protect the
tires from contact with oil, grease and fuel.
Cleaning tires
GWarning
Do not use power washers with circular jet
nozzles (concentrated-power jets) to clean
your vehicle, especially for cleaning tires. You
could otherwise damage the tires and cause
an accident.
Tire pressures
Recommended tire pressures
GWarning
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
You will find a table of recommended tire
pressures on the Tire and Loading
Information placard on the B-pillar on the
driver's side ( Y page 280). You will find a
table of tire pressures for various operating
conditions on the inside of your vehicle's fuel
filler flap.
Use a suitable pressure gauge. 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 using the on-board computer.
GWarning
Should the tire pressure drop repeatedly:
272Tire pressuresTires and wheels
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 272

Rcheck the tire for foreign bodies.
R check whether the wheel is losing air or the
valve is leaking.
R make sure that only a valve cap approved
by Mercedes-Benz is installed on the tire
valve.
Tire pressures that are too low have a
negative effect on vehicle safety, which could
lead you to cause an accident.
Only correct tire pressures when the tires are
cold. The tires are cold when the vehicle has
been parked for at least three hours or driven
for less than 1 mile (1.6 km). The tire
temperature changes depending on the
outside temperature, the vehicle speed and
the tire load. If the tire temperature changes
by 18 ‡ (10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi). Take
this into account when checking the pressure
of warm tires and only correct the tire
pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the reading
will be higher than if the tires were cold. This
is normal. Do not reduce the tire pressure to
the value specified for cold tires. The tire
pressure would otherwise be too low.
Observe the recommended tire pressure
specifications for cold tires on the Tire and
Loading Information placard on the B-pillar on
the driver's side.
i The specifications given on the following
Tire and Loading Information placard are
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications for your vehicle can be found
on the Tire and Loading Information placard
of your vehicle.
You will find recommended tire pressure
specifications : for cold tires and for a fully
loaded vehicle on the Tire and Loading
Information placard. The tire pressure
specifications apply to tires which are
installed at the factory.
Important notes on tire pressures
GWarning
If the tire pressure drops repeatedly, check
the tires for punctures from foreign objects
and/or whether air is leaking from the valves
or from around the rim.
The temperature and pressure of the tires
increase when the vehicle is in motion. This
is dependent on the driving speed and the
load.
If you wish to drive at high speeds of
100 mph (160 km/h) or higher when this is
allowed, use the tire pressure table on the
inside of the fuel filler flap to set the correct
tire pressures when the wheels are cold. If the
tire pressure is not set correctly, this can lead
to an excessive build up of heat and a sudden
loss of pressure.
For more information, contact a qualified
specialist workshop, e.g. an authorized
Mercedes-Benz Center.
i Ride comfort may be affected if the tire
pressure is adjusted to the recommended
value for speeds of over
100 mph(160 km/h).
Tire pressures273Tires and wheelsBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 273Z

Make sure that the tire pressure for normal
speeds is adopted again.
Additional specifications of tire pressure
values for loads can also be found on the tire
pressure table on the inside of the fuel filler
flap.
The tire pressure for emergency spare wheels
can be found:
R on the yellow label on the wheel rim of the
emergency spare wheel
R in the "Wheel and tire combinations"
section ( Y page 293) of this Operator's
Manual
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
i The specifications shown in the examples
in the tire pressure tables are only
examples. Tire pressure specifications are
vehicle-specific and may deviate from the
data shown here. The tire pressure
specifications that are valid for your vehicle
can be found on your vehicle's tire pressure
table.
The tire pressures in the tire pressure table
on the inside of the fuel filler flap are valid for
all approved tires installed at the factory,
unless stated otherwise.
Tire pressure table for all approved tires installed
at the factory (example)
If the tire pressure precedes a tire size, the
tire pressure specification is only valid for this
tire size. The vehicle loading conditions
"partially laden" or "fully laden" are specified
using a differing number of persons and
luggage in the table. The actual number of
seats may differ from this.
Tire pressure table with tire sizes (example)
Some tire pressure tables only show the rim
diameter instead of the complete tire size,
e.g. R18 . The rim diameter is a component of
the tire size and can be read from the tire
sidewall ( Y page 287).
Tire pressure too low or too high
Underinflated tires
GWarning
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Underinflated tires can:
R wear excessively and/or unevenly
R adversely affect fuel economy
274Tire pressuresTires and wheels
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 274

Rfail from being overheated
R adversely affect handling
Overinflated tires can:GWarning
Follow recommended tire inflation pressures.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Overinflated tires can:
R adversely affect handling
R wear excessively and/or unevenly
R be more likely to become damaged
R adversely affect ride comfort
R increase stopping distance
Checking tire pressures
Important safety notes
GWarning
Follow recommended tire inflation pressures.
Do not underinflate tires. Underinflated tires
wear excessively and/or unevenly, adversely
affect handling and fuel economy, and are
more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can
adversely affect handling and ride comfort,
wear unevenly, increase stopping distance,
and result in sudden deflation (blowout)
because they are more likely to become
punctured or damaged by road debris,
potholes etc.
Do not overload the tires by exceeding the
specified load limit as indicated on the Tire
and Loading Information placard on the
driver's door B-pillar. Overloading the tires
can overheat them, possibly causing a
blowout. Overloading the tires can also result
in handling or steering problems, or brake
failure.
Check the tire pressure at least once a month.
Only check and correct tire pressures when
the tires are cold ( Y page 272).
Checking the tire pressures manually
In order to determine and adjust the tire
pressures, proceed as follows:
XRemove the valve cap of the tire you wish
to check.XPress the tire pressure gauge securely onto
the valve.XRead 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.XIf necessary, increase the tire pressure to
the recommended value ( Y page 272).XIf 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.XScrew the valve cap onto the valve.XRepeat the steps for the other tires.
Tire pressure loss warning system
(Canada only)
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.
Tire pressures275Tires and wheelsBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 275Z

GWarning
If the Check Tire Pressure Soon message
appears in the multifunction display, one or
more tires are significantly underinflated.
Stop the vehicle as soon as possible and
inflate the tires to the pressure specified on
the vehicle's Tire and Loading Information
placard or (where available) in the tire
pressure table.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure. Underinflation also reduces fuel
efficiency and tire tread life, and may affect
the vehicle's handling and stopping ability.
Check all tires when cold, including the spare
tire, at least once a month. The tires should
be inflated to the recommended pressure.
This information can be found:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
or
R in the table for the tire pressure on the
inside of the fuel filler flap
GWarning!
The tire pressure loss warning system does
not provide a warning for wrongly selected tire
inflation pressures. Always adjust tire
inflation pressure according to the Tire and
Loading Information placard on the driver's
door B-pillar or on the tire inflation pressure
label located on the inside of the fuel filler flap.
The tire pressure loss warning system does
not replace regular checks of the tire inflation
pressures since a gradual pressure loss in
more than one tire cannot be detected by the
tire pressure loss warning system.
The tire pressure loss warning system is not
able to issue a warning due to a sudden
dramatic loss of tire inflation pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by carefully
applying the brakes and avoiding abrupt
steering maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on your vehicle.
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 cargo (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
XBefore restarting, refer to the Tire and
Loading Information placard on the
B-pillar on the driver's side or the tire
pressure table on the inside of the fuel filler
flap to ensure the tire pressure in all four
tires is set correctly for the current
operating conditions.XObserve the notes in the section on tire
pressures ( Y page 272).GWarning
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.
A tire with insufficient pressure results in
vehicle instability when driving, thus
increasing the risk of an accident.
XMake sure that the SmartKey is in
position 2 ( Y page 131) in the ignition lock.XPress the = or ; button to select the
Service menu.276Tire pressuresTires and wheels
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 276

XPress the 9 or : button to select
Tire Pressure .XPress 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:
XPress the a button.
The Tire Pressure Now OK? message
appears in the multifunction display.XPress 9 or : to select Yes.XPress 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.
If you wish to cancel the restart:
XPress the % button.
or
XIf the message: Tire Pressure now OK?
appears, use 9 or : to select
Cancel .XPress the a button.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitoring system
(USA only)
Important safety notes
If a tire pressure monitor is installed, the
vehicle's wheels have sensors installed that
monitor the tire pressures in all four tires. The
tire pressure monitor warns you when the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
in all wheels.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating a pressure loss or malfunction.
Depending on how the warning lamp flashes
or lights up, a tire pressure that is too low or
a malfunction in the tire pressure monitor is
displayed:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is
significantly too low. The tire pressure
monitor is not malfunctioning.
R if the warning lamp flashes for 60 seconds
and then remains lit constantly, the tire
pressure monitor is malfunctioning.GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the tire and loading
information table on the driver's door B-pillar
or the tire inflation pressure table on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the tire and loading information table or
the tire inflation pressure table, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor
(TPMS). An indicator lamp lights up if one or
more of your tires are significantly
underinflated. Accordingly, when the low tire
pressure indicator lamp lights up, you should
stop and check your tires as soon as possible,
and inflate them to the proper pressure.
Driving on a significantly underinflated tire
causes the tire to overheat and can lead to
tire failure.
Underinflation also reduces fuel efficiency
and tire tread life and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance and it is the driver's
responsibility to maintain correct tire
pressure, even if underinflation has not
Tire pressures277Tires and wheelsBA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 277Z

reached the level at which the low tire
pressure indicator lamp of the TPMS lights up.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure indicator lamp. When the
system detects a malfunction, the indicator
lamp will flash for approximately 1 minute and
then remain illuminated. This sequence will
continue upon subsequent vehicle start-ups
as long as the malfunction exists. When the
malfunction indicator is lit, the system may
not be able to detect or signal low tire
pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction indicator after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
i If the tire pressure monitor is
malfunctioning, it may take more than
10 minutes for the tire pressure warning
lamp to inform you of the malfunction by
flashing for 60 seconds and then remaining
lit.
When the malfunction has been rectified,
the tire pressure warning lamp goes out
after driving for a few minutes.
Information on tire pressures is displayed in
the multifunction display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the multifunction display.
i The tire pressure values indicated by the
on-board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure
values indicated by a pressure gauge arehigher than those shown by the on-board
computer. In this case, do not reduce the
tire pressures.
i The operation of the tire pressure monitor
can be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
operated in or near the vehicle.
i This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. This device must withstand any
interference received, including
interference that may cause undesired
operation.
Unauthorized modifications to the device
could void the user’s authority to operate
the equipment.
Checking tire pressure electronicallyXMake sure that the SmartKey is in
position 2 ( Y page 131) in the ignition lock.XPress the = or ; button to select the
Service menu.XPress the 9 or : button to select
Tire Pressure .XPress the a button.
The current tire pressure for each wheel will
be displayed in the multifunction display.
If the vehicle has been parked for longer than
20 minutes, the Tire pressures will be
displayed after driving a few
minutes message appears in the display.
After a teach-in period, the tire pressure
monitor automatically recognizes new wheels
or new sensors. As long as a clear allocation
of the tire pressure values to the individual
wheels is not possible, the Tire Pressure
Monitor Active message is shown instead
of the tire pressure display. The tire pressures
are already being monitored.
278Tire pressuresTires and wheels
BA 204 USA, CA Edition A 2011; 1; 5, en-UShereepeVersion: 3.0.3.62010-05-20T09:17:30+02:00 - Seite 278