2015 MERCEDES-BENZ SLK-Class tire pressure

Example: current tire pressure display
For information on the message display, refer to the "Checking the tire pressure electroni-
cally" section (Y page 320).
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
label 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 Infor-
mation placard or the tire pressure label, you should determine the proper tire pressure for
those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale illuminates,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale. Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate if the
system is not operating properly. The TPMS
malfunction indicator is combined with the
low tire pressure telltale. When the system
detects a malfunction, the warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi- cle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS malfunc-tions 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 func-
tioning properly. Always check the TPMS mal-
function telltale 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 prop-
erly.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
(Y page 314). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message isaligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(Y page 321). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 314).
The tire pressure monitor 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 Tire pressure
319Wheels and tires Z

event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering maneuvers.
The tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat- ing a pressure loss or malfunction. Whether
the warning lamp flashes or lights up indi-
cates whether a tire pressure is too low or the
tire pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is signif- icantly too low. The tire pressure monitor is
not malfunctioning.
R if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire 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 236).
If the tire pressure monitor is malfunctioning,
it may take more than ten minutes for the tire pressure warning lamp to inform you of the
malfunction by flashing for approximately one
minute and then remaining lit. When the mal- function has been rectified, the tire pressure
warning lamp goes out after a few minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured 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 val-
ues indicated by a pressure gauge are higher
than those shown by the on-board computer. In this case, do not reduce the tire pressures.
The operation of the tire pressure monitor can be affected by interference from radio trans-
mitting equipment (e.g. radio headphones,
two-way radios) that may be being operated
in or near the vehicle. Checking the tire pressure electroni-
cally X
Make sure that the SmartKey is in position
2 in the ignition lock (Y page 139).
X Press the 0059or0065 button on the steer-
ing wheel to select the Service Servicemenu.
X Press the 0063or0064 button to select
Tire Pressure
Tire Pressure.
X Press the 0076button.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle has been parked for over
20 minutes, the Tire pressure will be Tire pressure will be
displayed after driving a few
displayed after driving a few
minutes minutes message appears.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tire pressure value to the individual
wheels is not possible, the Tire Pressure Tire Pressure
Monitor Active Monitor Active display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i If an emergency spare wheel is mounted,
the system may continue to show the tire
pressure of the wheel that has been
removed for a few minutes. If this occurs,
note that the value displayed for the posi-
tion where the spare wheel is mounted is
not the same as the current tire pressure of
the emergency spare wheel.
Tire pressure monitor warning mes-
sages If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is shown in the multifunction display and the
yellow tire pressure monitor warning lamp
comes on.
R If the Please Correct Tire Pressure Please Correct Tire Pressure
message appears in the multifunction dis-
play, the tire pressure in at least one tire is 320
Tire pressureWheels and tires

too low and must be corrected at the next
opportunity.
R If the Check
Check Tires
Tiresmessage appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly
and the tires must be checked.
R If the Warning Tire Malfunction Warning Tire Malfunction
appears in the multifunction display, the
tire pressure in one or more tires has drop- ped suddenly and the tires must be
checked.
Observe the instructions and safety notes in
the display messages in the "Tires" section
(Y page 236).
i If the wheel positions on the vehicle are
rotated, the tire pressures may be dis-
played for the wrong positions for a short
time. This is rectified after a few minutes of
driving, and the tire pressures are displayed for the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor, all
existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the refer-
ence values for monitoring. In most cases, the tire pressure monitor will automatically
detect the new reference values after you
have changed the tire pressure. However, you
can also define reference values manually as
described here. The tire pressure monitor
then monitors the new tire pressure values.
X Set the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information placard on the driver's side
B-pillar (Y page 314).
Additional tire pressure values for different loads can also be found on the tire pressure
table on the inside of the fuel filler flap
(Y page 314).
X Make sure that the tire pressure is correct
on all four wheels. X
Make sure that the SmartKey is in position
2 in the ignition lock.
X Press the 0059or0065 button on the steer-
ing wheel to select the Service
Service menu.
X Press the 0063or0064 button to select
Tire Pressure Tire Pressure.
X Press the 0076button.
The multifunction display shows the cur-
rent tire pressure for the individual tires or
the Tire Tire pressure
pressure will
willbe
bedisplayed
displayed
after driving a few minutes
after driving a few minutes mes-
sage.
X Press the 0064button.
The Use Current Pressures as New
Use Current Pressures as New
Reference Values
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart: X Press the 0076button.
The Tire
Tire Pressure
Pressure Monitor
MonitorRestarted
Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
X Press the 0038button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
Canada IC: 2546A-MW2433A
IC: 2546A-GG4
IC: 2546A-MC34MA4 Tire pressure
321Wheels and tires Z

Tire labeling
Overview 0043
Uniform Tire Quality Grading Standard
(Ypage 330)
0044 DOT, Tire Identification Number
(Ypage 329)
0087 Maximum tire load (Y page 328)
0085 Maximum tire pressure (Y page 316)
0083 Manufacturer
0084 Tire material (Y page 329)
006B Tire size designation, load-bearing capa-
city and speed index (Y page 326)
006C Load index (Y page 328)
006D Tire name
The markings described above are on the tire in addition to the tire name (sales designa-
tion) and the manufacturer's name.
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident. Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle. 0043
Tire width
0044 Nominal aspect ratio in %
0087 Tire code
0085 Rim diameter
0083 Load bearing index
0084 Speed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S. manu-
facturing standards.
If "T" precedes the size description: these are compact emergency spare wheels at high tire
pressure, to be used only temporarily in an
emergency.
Tire width: tire width0043shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio0044is the
size ratio between the tire height and tire
width and is shown in percent. The aspect 326
All about
wheels and tiresWheels and tires

"(Y)" indicates that the maximum speed of
the tire is over 186 mph (300 km/h). Ask
the tire manufacturer about the maximum
speed. All-
weather
tires
and win-
ter tires Index Speed rating
Q M+S
3 up to 100 mph (160 km/h)
T M+S
3 up to 118 mph (190 km/h)
H M+S
3 up to 130 mph (210 km/h)
V M+S
3 up to 149 mph (240 km/h)
i
Not all tires with the M+S marking provide
the driving characteristics of winter tires. In
addition to the M+S marking, winter tires
also have the 004Dsnowflake symbol on
the tire wall. Tires with this marking fulfill
the requirements of the Rubber Manufac-
turers Association (RMA) and the Rubber
Association of Canada (RAC) regarding the
tire traction on snow. They have been espe- cially developed for driving on snow.
An electronic speed limiter prevents your
vehicle from exceeding the following speeds:
R all vehicles (except AMG vehicles):
130 mph (210 km/h)
R AMG vehicles: 155 mph (250 km/h)
R AMG vehicles with Handling Package:
174 mph (280 km/h)
The speed rating of tires mounted at the fac- tory 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 337).Further information about reading tire data
can be obtained from any qualified specialist
workshop.
Load index In addition to the load bearing index, load rat-
ing 0043may be imprinted after the letters that
identify speed rating on the sidewall of the tire
(Y page 326).
R If no specification is given: no text (as in the
example above), represents a standard
load (SL) tire
R XL or Extra Load: represents a reinforced
tire
R Light Load: represents a light load tire
R C, D, E: represents a load range that
depends on the maximum load that the tire
can carry at a certain pressure
i Tire data is vehicle-specific and may devi-
ate from the data in the example.
Maximum load rating 3
Or M+S004D for winter tires.328
All about wheels and tiresWheels and ti
res

Bar
Metric unit for tire pressure. 14.5038 pounds
per square inch (psi) and 100 kilopascals
(kPa) are the equivalent of 1 bar.
DOT (Department of Transportation)
DOT marked tires fulfill the requirements of
the United States Department of Transporta- tion.
Normal occupant weight
The number of occupants which the vehicle is
designed for, multiplied by 68 kilograms
(150 lb).
Uniform Tire Quality Grading Standards
A uniform standard to grade the quality of
tires with regards to tread quality, tire traction and temperature characteristics. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Recommended tire pressure
The recommended tire pressure applies to
the tires mounted at the factory.
The Tire and Loading Information placard con- tains the recommended tire pressures for
cold tires on a fully loaded vehicle and for themaximum permissible vehicle speed.
The tire pressure table contains the recom-
mended pressures for cold tires for various
operating conditions, i.e. differing load and
speed conditions.
Increased vehicle weight due to optional
equipment
This is the combined weight of all standard
and optional equipment available for the vehi-
cle, regardless of whether it is actually instal-
led on the vehicle or not.
Rim
This is the part of the wheel on which the tire
is mounted. GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. 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 identifica-
tion. 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, lug-
gage and the drawbar noseweight, if applica-
ble. 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, occu-
pants, fuel, luggage and the drawbar nose-
weight, if applicable). The gross vehicle
weight rating is specified on the vehicle iden-
tification 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 corre-
sponds to 1 psi. Another unit for tire pressure is bar. There are 100 kilopascals (kPa) to
1 bar. 330
All about wheels and tiresWheels and tires

Load index
In addition to the load-bearing index, the load
index may also be imprinted on the sidewall ofthe tire. This specifies the load-bearing capa-
city more precisely.
Curb weight
The weight of a vehicle with standard equip-
ment including the maximum capacity of fuel, oil and coolant. It also includes the air-condi- tioning system and optional equipment if
these are installed in the vehicle, but does not
include passengers or luggage.
Maximum load rating
The maximum tire load is the maximum per-
missible weight in kilograms or lbs 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.
Aspect ratio
Relationship between tire height and tire
width in percent.
Tire pressure
This is pressure inside the tire applying an
outward force to each square inch of the tire's
surface. The tire pressure is specified in
pounds per square inch (psi), in kilopascal
(kPa) or in bar. The tire pressure should only
be corrected when the tires are cold. Cold tire pressure
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less than
1 mile (1.6 km).
Tread
The part of the tire th at comes into contact
with the road.
Bead
The tire bead ensures that the tire sits
securely on the wheel. There are several steel
wires in the bead to prevent the tire from
coming loose from the wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras that weigh more than the replaced standard
parts and more than 2.3 kilograms (5 lbs).
These optional extras, such as high-perform-
ance brakes, level control, a roof rack or a
high-performance battery, are not included in
the curb weight and the weight of the acces-
sories.
TIN (Tire Identification Number)
This is a unique identifier which can be used
by a tire manufacturer to identify tires, for
example for a product recall, and thus identify the purchasers. The TIN is made up of the
manufacturer's identity code, tire size, tire
type code and the manufacturing date.
Load bearing index
The load bearing index (also load index) is a
code that contains the maximum load bearing capacity of a tire. All about wheels and tires
331Wheels and tires Z

Traction
Traction is the result of friction between the
tires and the road surface.
Treadwear indicators
Narrow bars (tread wear bars) that are dis-
tributed over the tire tread. If the tire tread is level with the bars, the wear limit of 00CDin
(1.6 mm) has been reached.
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) multiplied by the num-
ber of seats in the vehicle. Changing a wheel
Flat tire
The "Breakdown assistance" section
(Y page 292) contains information and notes
on how to deal with a flat tire. Information on driving with MOExtended tires in the event of
a flat tire can be found under "MOExtended
tires (tires with run-flat characteristics"
(Y page 293). Rotating the wheels
G
WARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
! On vehicles equipped with a tire pressure
monitor, electronic components are loca-
ted in the wheel. Tire-mounting tools should not be used
near the valve. This could damage the elec-
tronic components.
Only have tires changed at a qualified spe-cialist workshop.
Always pay attention to the instructions and
safety notes when changing a wheel
(Y page 333).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in the center.
If your vehicle's tire configuration allows, you can rotate the wheels according to the inter-
vals in the tire manufacturer's warranty book
in your vehicle documents. If no warranty
book is available, the tires should be rotated
every 3,000 to 6,000 miles (5,000 to
10,000 km), or earlier if tire wear requires. Do not change the direction of wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressure and, if nec- essary, restart the tire pressure loss warning
system or the tire pressure monitor. Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk of hydroplaning. You will only gain these ben-
efits if the correct direction of rotation is
maintained.
An arrow on the sidewall of the tire indicates
its correct direction of rotation. Storing wheels
Store wheels that are not being used in a cool, dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel. 332
Changing a wheelWheels and tires