2015 MERCEDES-BENZ CLA-Class Owner's Manual

weeks when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire pres-
sure 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
Information placard or, if available, 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 lights up,
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, 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 responsi-
bility to maintain correct tire pressure, even if
underinflation has not reached the level to
trigger illumination of the TPMS low tire pres-
sure telltale.
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 telltale. When the sys-
tem 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 illu-
minated, 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 incom-
patible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from functioning properly. Always check the
TPMS malfunction 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 properly.
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 322). 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 is aligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(Y page 328). 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 322).
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
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. Tire pressure
327Wheels and tires Z

In addition to the warning lamp, a message
appears in the multifunction display. Observe
the information on display messages
(Y page 239).
It may take up to ten minutes for a malfunc-
tion of the tire pressure monitor to be indica-
ted. A malfunction will be indicated by the tire pressure warning lamp flashing for approx-
imately one minute and then remaining lit.
When the malfunction 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 141).
X Press =or; on the steering wheel
to select the Serv.
Serv. menu.
X Press the 9or: button to select
Tire Pressure Tire Pressure.
X Press the abutton.
The current tire pressure of each tire is
shown in the multifunction display.
If the vehicle was parked for longer than
20 minutes, the Tire pressure will be
Tire pressure will be
displayed after driving a few
displayed after driving a few
minutes minutes message is shown.
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 message is shown instead
of the tire pressure display. The tire pressures
are already being monitored.
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
too low and must be corrected at the next
opportunity.
R If the Check Tire Pressure Check Tire Pressure message
appears in the multifunction display, the
tire pressure in one or more tires has drop- ped significantly and the tires must be
checked.
R If the Tire Pressure Warning Tire Tire Pressure Warning Tire
Failure
Failure message appears in the multi-
function display, the tire pressure in one or
more tires has dropped suddenly and the
tires must be checked.
Observe the instructions and safety notes in
the display messages in the "Tires" section
(Y page 239).
If the wheel positions on the vehicle are rota- ted, the tire pressures may be displayed 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 cor-
rect 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 328
Tire pressureWheels and tires

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 322).
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 159).
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 (Y page 141).
X Press =or; on the steering wheel
to select the Serv. Serv.menu.
X Press the 9or: button to select
Tire Pressure
Tire Pressure.
X Press the abutton.
The multifunction display shows the cur-
rent tire pressure for each tire or the Tire
Tire
pressure will be displayed after
pressure will be displayed after
driving a few minutes driving a few minutes message.
X Press the :button.
The multifunction display shows the Use
Use
current
current pressures
pressures as
asnew
new reference
reference
values
values message.
If you wish to confirm the restart: X Press the abutton.
The Tire Press. Monitor Restarted
Tire Press. Monitor 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 %button.
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
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.
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 permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures 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 Loading the vehicle
329Wheels and tires Z

of the vehicle weight, all vehicle occu-
pants, 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 maxi-
mum gross axle weight rating for the
front or rear axle. :
B-pillar, driver's side Maximum permissible gross vehicle
weight rating
X
Specification for maximum gross vehicle
weight :is listed in the Tire and Loading
Information placard: "The combined weight of occupants and cargo should never
exceed XXX kilograms or XXX lbs."
The gross weight of all vehicle occupants,
load and luggage must not exceed the speci-
fied value. i
The specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The maximum permis-
sible gross vehicle weight rating is vehicle-
specific and may differ from that in the
illustration. You can find the valid maximum permissible gross vehicle weight rating for
your vehicle on the Tire and Loading Infor-
mation placard. Number of seats
Maximum number of seats
:indicates the
maximum number of occupants allowed to
travel in the vehicle. This information can be
found on the Tire and Loading Information
placard.
i The specifications shown on the Tire and
Loading Information placard in the illustra-
tion are examples. The number of seats is
vehicle-specific and can differ from the
details shown. The number of seats in your vehicle can be found on the Tire and Load-
ing Information placard. Determining the correct load limit
Step-by-step instructions The following steps have been developed as
required of all manufacturers under Title 49,
Code of U.S. Federal Regulations, Part 575
pursuant to the "National Traffic and Motor
Vehicle Safety Act of 1966". 330
Loading the vehicleWheels and tires

X
Step 1: Locate the statement "The com-
bined weight of occupants and cargo
should never exceed XXX kg or XXX lbs." on your vehicle’s Tire and Loading Information
placard.
X Step 2: Determine the combined weight of
the driver and passengers that will be riding
in your vehicle.
X Step 3: Subtract the combined weight of
the driver and passengers from XXX kilo-
grams or XXX lbs.
X Step 4: The resulting figure equals the
available amount of cargo and luggage load
capacity. For example, if the "XXX" amount
equals 1400 lbs and there will be five
150-lb passengers in your vehicle, the
amount of available cargo and luggage load
capacity is 650 lbs (1400 - 750 (5 x 150) = 650 lbs).
X Step 5: Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely exceed
the available cargo and luggage load capa- city calculated in step 4. Loading the vehicle
331Wheels and tires Z

Example: steps 1 to 3
The following table shows examples on how to calculate total and cargo load capacities with varying seating configurations and number and size of occupants. The following examples usea load limit of 1500 lbs (680 kg). This is for illustration purposes only. Make sure you are
using the actual load limit for your vehicle stated on your vehicle's Tire and Loading Information
placard (Y page 329).
The greater the combined weight of the occupants, the lower the maximum luggage load.
Step 1 Example 1 Example 2 Example 3
Combined maximum
weight of occupants
and cargo (data from
the Tire and Loading
Information placard)
1500 lbs (680 kg) 1500 lbs (680 kg) 1500 lbs (680 kg)
Step 2
Example 1 Example 2 Example 3
Number of people in
the vehicle (driver
and occupants)
5 3 1
Distribution of the
occupants
Front: 2
Rear: 3 Front: 1
Rear: 2 Front: 1
Weight of the occu-
pants
Occupant 1: 150 lbs
(68 kg)
Occupant 2: 180 lbs
(82 kg)
Occupant 3: 160 lbs (73 kg)
Occupant 4: 140 lbs
(63 kg)
Occupant 5: 120 lbs
(54 kg) Occupant 1: 200 lbs
(91 kg)
Occupant 2: 190 lbs
(86 kg)
Occupant 3: 150 lbs (68 kg) Occupant 1: 150 lbs
(68 kg) Gross weight of all
occupants
750 lbs (340 kg) 540 lbs (245 kg) 150 lbs (68 kg)332
Loading the vehicleWheels and tires

Step 3
Example 1 Example 2 Example 3
Permissible load
(maximum gross vehi-
cle weight rating from
the Tire and Loading
Information placard
minus the gross
weight of all occu-
pants) 1500 lbs (680 kg)
Ò
750 lbs (340 kg) =
750 lbs (340 kg) 1500 lbs (680 kg)
Ò
540 lbs (245 kg)
=960 lbs (435 kg) 1500 lbs (680 kg)
Ò
150 lbs (68 kg) =
1350 lbs (612 kg) Vehicle identification plate
Even if you have calculated the total cargo
carefully, you should still make sure that the
gross vehicle weight rating and the gross axle weight rating are not exceeded. Details can
be found on the vehicle identification plate on the B-pillar on the driver's side of the vehicle
(Y page 329).
Permissible Gross Vehicle Weight Rating
(GVWR): the gross weight of the vehicle, all
passengers, load and trailer load/noseweight (if applicable) must not exceed the permissi-
ble gross vehicle weight.
Gross Axle Weight Rating (GAWR): the
maximum permissible weight that can be car- ried by one axle (front or rear axle).
To ensure that your vehicle does not exceed
the maximum permissible values (gross vehi-
cle weight and maximum gross axle weight
rating), have your loaded vehicle (including
driver, occupants, cargo, and full trailer load if applicable) weighed on a suitable vehicle
weighbridge. All about wheels and tires
Uniform Tire Quality Grading Stand-
ards
Overview of Tire Quality Grading Stand- ards Uniform Tire Quality Grading Standards are
U.S. government specifications. Their pur-
pose is to provide drivers with uniform relia-
ble information on tire performance data. Tire
manufacturers have to grade tires using three
performance factors: :tread wear grade, ;
traction grade and =temperature grade.
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.
Quality grades can be found, where applica-
ble, on the tire sidewall between tread shoul-
der and maximum section width. All about wheels and tires
333Wheels and tires Z

Example:
R Treadwear grade: 200
R Traction grade: AA
R Temperature grade: A
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
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, how-
ever, and may depart significantly from the
norm due to variations in driving habits, ser-
vice practices and differences in road char-
acteristics and climate.
Traction G
WARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor- nering, hydroplaning, or peak traction char-
acteristics.
! Avoid wheelspin. This can lead to damage
to the drive train.
The traction grades – from highest to lowest –
are AA, A, B and C. Those grades represent
the tire's ability to stop on wet pavement 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 surfa-
ces.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Mercedes-Benz recommends a minimum
tread depth of ãin (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 319). Winter tires can
reduce the braking distance on snow-covered surfaces in comparison with summer tires.
The braking distance is still much further thanon surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) (Y page 320).
Temperature G
WARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, 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, representing the tire's resistance to
the generation of heat and its ability to dissi- pate heat when tested under controlled con-
ditions 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. 334
All about
wheels and tiresWheels and tires