2013 MERCEDES-BENZ CLA-CLASS tyre pressure

wheels and tyres for damage. Hidden tyre
damage could also be causing the unusual
handling characteristics. If you find no
signs of damage, have the wheels and tyres
checked at a qualified specialist workshop.
R When parking your vehicle, make sure that
the tyres do not get deformed by the kerb
or other obstacles. If it is necessary to drive
over kerbs, speed humps or similar eleva-
tions, try to do so slowly and at an obtuse
angle. Otherwise, the tyres, particularly the
sidewalls, may be damaged.
Regular checking of wheels and tyres
GWARNING
Damaged tyres can cause tyre inflation pres-
sure loss. As a result, you could lose control
of your vehicle. There is a risk of accident.
Check the tyres regularly for signs of damage
and replace any damaged tyres immediately.
Regularly check the wheels and tyres 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
tyre pressure. Pay particular attention to
damage such as:
R cuts in the tyres
R punctures
R tears in the tyres
R bulges on tyres
R deformation or severe corrosion on wheels
Regularly check the tyre tread depth and the
condition of the tread across the whole width
of the tyre ( Y page 317). If necessary, turn
the front wheels to full lock in order to inspect
the inner side of the tyre surface.
All wheels must have a valve cap to protect
the valve against dirt and moisture. Do not fit
anything onto the valve other than the stand-
ard valve cap or other valve caps approved by
Mercedes-Benz for your vehicle. Do not fit any
other valve caps or systems, e.g. tyre pres-
sure monitoring systems.
Regularly check the pressure of all the tyres,
particularly prior to long trips. Adjust the tyre
pressure as necessary ( Y page 319).
Observe the notes on the emergency spare
wheel ( Y page 331).
The service life of tyres depends on various
factors, including the following:
R Driving style
R Tyre pressure
R Mileage
Important safety notes on the tyre
tread
GWARNING
Insufficient tyre tread will reduce tyre trac-
tion. The tyre is no longer able to dissipate
water. This means that on wet road surfaces,
the risk of aquaplaning increases, in particular
where speed is not adapted to suit the driving
conditions. There is a risk of accident.
If the tyre pressure is too high or too low, tyres
may exhibit different levels of wear at differ-
ent locations on the tyre tread. Thus, you
should regularly check the tread depth and
the condition of the tread across the entire
width of all tyres.
Minimum tyre tread depth for:
R summer tyres: 3 mm
R M+S tyres: 4 mm
For safety reasons, replace the tyres before
the legally prescribed limit for the minimum
tyre tread depth is reached..
Selecting, fitting and replacing tyres
R Only fit tyres and wheels of the same type
and make.
Exception: it is permissible to fit a different
type or make in the event of a flat tyre.
Observe the "MOExtended tyres (tyres with
Operation317Wheels and tyresZProCarManuals.com

run-flat characteristics)" section
( Y page 298).
R Only fit tyres of the correct size onto the
wheels.
R Run in new tyres at moderate speeds for
the first 100 km. They only reach their full
performance after this distance.
R Do not drive with tyres which have too little
tread depth. This otherwise significantly
reduces the traction on wet roads (aqua-
planing).
R Replace the tyres after six years at the lat-
est, regardless of wear.
Observe the notes on the emergency spare
wheel ( Y page 331).
MOExtended tyres (tyres with run-flat
characteristics)
With MOExtended tyres (tyres with run-flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tyres.
MOExtended tyres may only be used in con-
junction with an active tyre pressure loss
warning system and only on wheels specifi-
cally tested by Mercedes-Benz.
Notes on driving with MOExtended tyres with
a flat tyre ( Y page 298).
i Vehicles with MOExtended tyres are not
equipped with a TIREFIT kit at the factory.
It is therefore recommended that you addi-
tionally equip your vehicle with a TIREFIT kit
if you fit tyres that do not feature run-flat
characteristics, e.g. winter tyres. A TIREFIT
kit can be obtained from a qualified spe-
cialist 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 324).
Driving with summer tyres
At temperatures below +7 †, summer tyres
lose elasticity and therefore traction and
braking power. Change the tyres on your vehi-
cle to M+S tyres . Using summer tyres at very
cold temperatures could cause tears to form,
thereby damaging the tyres permanently.
Mercedes-Benz cannot accept responsibility
for this type of damage.
M+S tyres
GWARNING
M+S tyres with a tyre tread depth of less than
4 mm are not suitable for use in winter as they
do not provide sufficient traction. There is a
risk of accident.
M+S tyres with a tread depth of less than
4 mm must be replaced.
At temperatures below +7 †, use winter tyres
or all-season tyres. Both types of tyre are
identified by the M+S marking.
Only winter tyres bearing the i snowflake
symbol in addition to the M+S marking pro-
vide the best possible grip in wintry road con-
ditions. Only these tyres will allow driving
safety systems such as ABS and ESP ®
to
function optimally in winter. These tyres have
been developed specifically for driving in
snow.
Use M+S tyres of the same make and tread
on all wheels to maintain safe handling char-
acteristics.
Always observe the maximum permissible
speed specified for the M+S tyres you have
fitted.
If you fit M+S tyres that have a lower maxi-
mum permissible speed than that of the vehi-
cle, affix an appropriate warning sign in the
driver's field of vision. This can be obtained
at a qualified specialist workshop.
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Under these circumstances, you should also
restrict the maximum speed of the vehicle
using permanent SPEEDTRONIC so that it
does not exceed the maximum permissible
speed for the M+S tyres( Y page 173).
When you have fitted the M+S tyres:XCheck the tyre pressures ( Y page 319).XRestart the tyre pressure loss warning sys-
tem ( Y page 321).
For more information on driving with the
emergency spare wheel, see ( Y page 331).
Snow chains
GWARNING
If snow chains are fitted to the rear wheels,
they may scrape against the vehicle body or
chassis components. This could cause dam-
age to the vehicle or the tyres. There is a risk
of an accident.
To avoid hazardous situations:
R never fit snow chains on the rear wheels
R always fit snow chains in pairs to the front
wheels.
! Vehicles with steel wheels: if you wish
to fit snow chains to steel wheels, make
sure that you remove the respective
wheels' hubcaps first. The hubcaps may
otherwise be damaged.
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains that
have been specially approved for your vehicle
by Mercedes-Benz, or that are of a corre-
sponding standard of quality.
If you intend to fit snow chains, please bear
the following points in mind:
R snow chains cannot be fitted to all wheel-
tyre combinations. Permissible wheel-tyre
combinations ( Y page 329).
R only use snow chains when the road sur-
face is completely snow-covered. Remove
the snow chains as soon as possible when
you come to a road that is not snow-cov-
ered.
R local regulations may restrict the use of
snow chains. Observe the appropriate reg-
ulations if you wish to fit snow chains.
R do not exceed the maximum permissible
speed of 50 km/h.
R when snow chains are fitted, never use
Active Parking Assist ( Y page 186).
i You may wish to deactivate
ESP ®
(Y page 68) when pulling away with
snow chains fitted. This way you can allow
the wheels to spin in a controlled manner,
achieving an increased driving force (cut-
ting action).
For more information on driving with the
emergency spare wheel, see ( Y page 331).
Tyre pressure
Tyre pressure specifications
GWARNING
Underinflated or overinflated tyres pose the
following risks:
R the tyres may burst, especially as the load
and vehicle speed increase.
R the tyres may wear excessively and/or
unevenly, which may greatly impair tyre
traction.
R the driving characteristics, as well as steer-
ing and braking, may be greatly impaired.
There is a risk of an accident.
Observe the recommended tyre pressure and
check the tyre pressure of all the tyres includ-
ing the spare wheel:
R at least every two weeks
R when the load changes
R before embarking on a longer journey
R for changed operating conditions, e.g. off-
road driving
If necessary, correct the tyre pressure.
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GWARNING
If you fit unsuitable accessories onto tyre
valves, the tyre valves may be overloaded and
malfunction, which can cause tyre pressure
loss. Due to their design, retrofitted tyre pres-
sure monitors keep the tyre valve open. This
can also result in tyre pressure loss. There is
a risk of accident.
Only screw standard valve caps or valve caps
specifically provided by Mercedes-Benz for
your vehicle onto the tyre valve.
GWARNING
If the tyre pressure drops repeatedly, the
wheel, valve or tyre may be damaged. Tyre
pressure that is too low may result in a tyre
blow-out. There is a risk of accident.
R Check the tyre for foreign objects.
R Check whether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
HEnvironmental note
Check the tyre pressure regularly, at least
every 14 days.
You will find a table of tyre pressures for var-
ious operating conditions on the inside of
your vehicle's fuel filler flap.
Operation with an emergency spare
wheel (Y page 331).
Operation with a trailer: the applicable
value for the rear tyres is the maximum tyre
pressure value stated in the table inside the
fuel filler flap.
The table inside the fuel filler flap may state
tyre pressures for different load conditions.
These are defined in the table as different
numbers of passengers and amounts of lug-
gage. The actual number of seats may vary;
for more information, please refer to the vehi-
cle's registration documents.
If tyre sizes are not specified, the tyre pres-
sures stated on the tyre pressure information
label apply for all tyres approved for this vehi-
cle.
If a tyre size precedes a tyre pressure, the
following tyre pressure information is only
valid for that tyre size.
Use a suitable pressure gauge to check the
tyre pressure. The outer appearance of a tyre
does not permit any reliable conclusion about
the tyre pressure.
If possible, only correct tyre pressures when
the tyres are cold.
The tyres are cold:
R if the vehicle has been parked with the tyres
out of direct sunlight for at least three
hours and
R if the vehicle has not been driven further
than 1.6 km
Depending on the ambient temperature, the
speed at which you are driving and the load
on the tyres, the tyre temperature and thus
the tyre pressure changes by approximately
10 kPa (0.1 bar/1.5 psi) per 10 †. Take this
into account when checking the pressure of
warm tyres. Only correct the tyre pressure if
it is too low for the current operating condi-
tions.
Driving with tyre pressure that is too high or
too low can:
R shorten the service life of the tyres
R cause increased tyre damage
R have a negative effect on handling charac-
teristics and thus the driving safety (e.g.
aquaplaning)
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iThe tyre pressure values given for low
loads are minimum values which offer you
good ride comfort characteristics.
However, you can also use the values given
for higher loads. These are permissible and
will not adversely affect the running of the
vehicle.
Tyre pressure loss warning system
General notes
While the vehicle is in motion, the tyre pres-
sure loss warning system monitors the set
tyre pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tyre. 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 dis-
play.
You can recognise the tyre pressure loss
warning by the Run Flat Indicator
active Restart with OK message which
appears in the Service menu of the multi-
function display. Further information on the
message display can be found under "Restart-
ing the tyre pressure loss warning system"
( Y page 321).
Important safety notes
The tyre pressure warning system does not
warn you of an incorrectly set tyre pressure.
Observe the notes on the recommended tyre
pressure ( Y page 319).
The tyre pressure loss warning does not
replace the need to regularly check the tyre
pressures. An even loss of pressure on sev-
eral tyres at the same time cannot be detec-
ted by the tyre pressure loss warning system.
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre 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 manoeuvres.
The function of the tyre pressure loss warning
system is limited or delayed if:
R snow chains are fitted to your vehicle's
tyres.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tyre pressure loss warn-
ing system
Restart the tyre pressure loss warning system
if you have:
R changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
XBefore restarting, make sure that the tyre
pressures are set properly on all four tyres
for the respective operating conditions.
The recommended tyre pressures can be
found in the table on the fuel filler flap.
The tyre pressure loss warning system can
only give reliable warnings if you have set
the correct tyre pressure. If an incorrect
tyre pressure is set, these incorrect values
will be monitored.XObserve the notes in the section on tyre
pressures ( Y page 319).XMake sure that the key is in position 2 in
the ignition lock ( Y page 145).XPress = or ; on the steering wheel
to select the Service menu.XPress the 9 or : button to select
Tyre press. .XPress the a button.
The Run Flat Indicator active
Restart with OK message appears in the
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If you wish to confirm the restart:XPress the a button.
The Tyre press. now OK? message
appears in the multifunction display.XPress the 9 or : button to select
Yes .XPress the a button.
The Run Flat Indicator restarted
message appears in the multifunction dis-
play.
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
If you wish to cancel the restart:
XPress the % button.
or
XWhen the Tyre press. now OK? message
appears, press the 9 or : button to
select Cancel .XPress the a button.
The tyre pressure values stored at the last
restart will continue to be monitored.
Tyre pressure monitor
General notes
If a tyre pressure monitor system is fitted, the
vehicle's wheels have sensors fitted that
monitor the tyre pressures in all four tyres.
The tyre pressure monitor warns you if the
pressure drops in one or more of the tyres.
The tyre pressure monitor only functions if
the corresponding sensors are fitted to all
wheels.
Information on tyre pressures is shown in the
multifunction display. After a few minutes of
driving, the current tyre pressure of each tyre
is shown in the Service menu of the multi-
function display. For further information on
displaying this message, refer to the "Check-
ing the tyre pressure electronically" section
( Y page 323).
Important safety notes
It is the driver's responsibility to set the tyre
pressure to the recommended cold tyre pres-
sure suitable for the operating situation
( Y page 319). Note that the correct tyre pres-
sure for the current operating situation must
first be taught-in to the tyre pressure monitor.
If there is a substantial loss of pressure, the
warning threshold for the warning message is
aligned to the reference values taught-in.
Restart the tyre pressure monitor after
adjusting to the cold tyre pressure
( Y page 324). The current pressures are
saved as new reference values. This will
ensure that a warning message will only
appear if the tyre pressure drops significantly.
The tyre pressure monitor does not warn you
of an incorrectly set tyre pressure. Observe
the notes on the recommended tyre pressure
( Y page 319).
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre 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 manoeuvres.
The tyre pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat-
ing a pressure loss or malfunction. Depending
on how the warning lamp flashes or lights up,
a tyre pressure that is too low or a malfunc-
tion in the tyre pressure monitor is indicated:
R if the warning lamp is lit continuously, the
tyre pressure on one or more tyres is sig-
nificantly too low. The tyre pressure moni-
tor is not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tyre pressure monitor is malfunctioning.
i In addition to the warning lamp, a mes-
sage appears in the multifunction display.
Further information can be found on
( Y page 248).
If the tyre pressure monitor is malfunctioning,
it may take more than ten minutes for the tyre
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pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the fault
has been rectified, the tyre pressure warning
lamp goes out after you have driven for a few
minutes.
The tyre pressure values indicated by the on-
board computer may differ from those meas-
ured at a filling station using a pressure
gauge. The tyre pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tyre pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the tyre
pressures.
The operation of the tyre pressure monitor
can be affected by interference from radio
transmitting equipment (e.g. radio head-
phones, two-way radios) that may be being
operated in or near the vehicle.
Checking the tyre pressure electroni-
callyXMake sure that the key is in position 2 in
the ignition lock ( Y page 145).XPress the = or ; button on the steer-
ing wheel to select the Service menu.XPress the 9 or : button to select
Tyre pressure .XPress the a button.
The current tyre pressure for each wheel
will be displayed in the multifunction dis-
play.
If the vehicle has been parked for over
20 minutes, the Tyre pressures will be
displayed after a few minutes of
driving message appears.
After a teach-in period, the tyre pressure
monitor automatically recognises new
wheels or new sensors. As long as a clear
allocation of the tyre pressure values to the
individual wheels is not possible, the Tyre
pressure monitor active display mes-
sage is shown instead of the tyre pressure
display. The tyre pressures are already being
monitored.
i If an emergency spare wheel is fitted, the
system may continue to show the tyre pres-
sure of the wheel that has been removed
for a few minutes. If this occurs, note that
the value displayed for the position where
the spare wheel is fitted is not the same as
the current tyre pressure of the emergency
spare wheel.
Warning messages of the tyre pressure
monitor
If the tyre pressure monitor detects a pres-
sure loss in one or more tyres, a warning mes-
sage is shown in the multifunction display and
the yellow tyre pressure monitor warning light
comes on.
R If the Please correct tyre pressure
message appears in the multifunction dis-
play, the tyre pressure in at least one tyre
is too low and must be corrected at the next
opportunity.
R If the Tyre pressure Check tyre(s)
message appears in the multifunction dis-
play, the tyre pressure in one or more tyres
has dropped significantly and the tyres
must be checked.
R If the Tyre pressure Caution, tyre
defect message appears in the multifunc-
tion display, the tyre pressure in one or
more tyres has dropped suddenly and the
tyres must be checked.
Observe the instructions and safety notes in
the display messages in the "Tyres" section
( Y page 248).
i If the wheel positions on the vehicle are
interchanged, the tyre pressures may be
displayed for the wrong positions for a
short time. This is rectified after a few
minutes of driving and the tyre pressures
are displayed for the correct positions.
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Restarting the tyre pressure monitor
When you restart the tyre pressure monitor,
all existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tyre pressures as the refer-
ence values for monitoring. In most cases, the
tyre pressure monitor will automatically
detect the new reference values after you
have changed the tyre pressure. However,
you can also define reference values man-
ually as described here. The tyre pressure
monitor then monitors the new tyre pressure
values.
XUse the table on the inside of the fuel filler
flap to ensure that the tyre pressure is set
correctly in all four tyres for the current
operating conditions.
Also observe the notes in the section on
tyre pressures ( Y page 319).XMake sure that the key is in position 2 in
the ignition lock.XPress the = or ; button on the steer-
ing wheel to select the Service menu.XPress the 9 or : button to select
Tyre pressure .XPress the a button.
The multifunction display shows the cur-
rent tyre pressure for the individual tyres or
the Tyre pressures will be dis‐
played after a few minutes of driv‐
ing message.XPress the : button.
The Use current pressures as new
reference values message appears in
the multifunction display.
If you wish to confirm the restart:
XPress the a button.
The Tyre press. monitor restarted
message appears in the multifunction dis-
play.
After you have driven for a few minutes, the
system checks whether the current tyre
pressures are within the specified range.The new tyre pressures are then accepted
as reference values and monitored.
If you wish to cancel the restart:
XPress the % button.
The tyre pressure values stored at the last
restart will continue to be monitored.
Changing a wheel
Flat tyre
You can find information on what to do in the
event of flat tyre in the "Flat tyre" section
( Y page 298). Information on driving with
MOExtended tyres in the event of a flat tyre
can be found under "Breakdown assistance"
( Y page 298).
Vehicles with an emergency spare
wheel: in the event of a flat tyre, the emer-
gency spare wheel is fitted according to the
description under "Fitting a wheel"
( Y page 325).
Interchanging the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tyres have different dimensions.
The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Interchange front and rear wheels only if the
wheels and tyres are of the same dimensions.
! On vehicles fitted with a tyre pressure
monitor, electronic components are loca-
ted in the wheel.
Tyre-fitting tools should not be applied in
the area of the valve, as this could damage
the electronic components.
Only have tyres changed at a qualified spe-
cialist workshop.
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