2013 MERCEDES-BENZ SL-CLASS ROADSTER Owners Manual

alternate tires and wheels allow the TPMS to
continue to function properly.
It is the driver's responsibility to set the tire
inflation to the recommended cold tire
pressure suitable to the operating situation
( Y page 529). Note that the correct tire
pressure 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 adjusting to the cold tire
pressure. ( Y page 536) The current
pressures are

saved as new reference values.
As a result, a warning message will appear if
the tire pressure 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 529).
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.
If a tire pressure monitor system is installed,
the vehicle's wheels have sensors installed
that monitor the tire pressures in all four tires.
The tire pressure monitor warns you if the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct wheel electronics units are installed
on each wheel.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Whether the
warning lamp flashes or lights up indicates
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 significantly too low. The tire pressure
monitor is not malfunctioning.
R USA only: if the warning lamp flashes for
around a minute and then remains lit
constantly, the tire pressure monitor is
malfunctioning.
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.
USA only: if there is a malfunction with the
tire pressure monitor it can take more than
ten minutes until the malfunction is shown by
the tire pressure warning lamp flashing for
approximately one minute and then lighting
up continuously. 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
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 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
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
i USA only:
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 accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment. Tire pressure
535
Wheels and tires Z

i
Canada only:
This device complies with RSS-210
of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
Checking tire pressure electronically X
Make sure that the key is in position
2(Y page 135) in the ignition lock.
X Press the = or ; button 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 current

tire pressure for each wheel will
be displayed in the multifunction display.
If the vehicle has been parked for over
20 minutes, the message Tire pressure
will be displayed after driving a
few minutes appears.
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 display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
Tire pressure monitor warning
messages If the tire pressure monitor detects a
significant
pressure

loss on one or more tires,
a warning message is shown in the
multifunction display. A warning tone also sounds and the tire pressure warning lamp
lights up in the instrument cluster.
Each
tire

that is affected by a significant loss
of pressure is highlighted in the pressure
display.
X If the Correct Tire Pressure message
appears in

the multifunction display, check
the tire pressure on all four wheels and
correct it if necessary.
i If the wheel positions on the vehicle are
interchanged, 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 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
reference 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.
X Set the tire pressure to the value
recommended for the corresponding
driving situation on the Tire and Loading
Information placard on the driver's side
B-pillar( Y page 529).
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 529).
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 = or ; button on the
steering wheel to select the Service
menu.536
Tire pressure
Wheels and tires

X
Press the 9 or : button to select
Tire Pressure.
X Press the a button.
The multifunction display shows the
current tire
pressure for the individual tires
or the Tire Pressure will be
displayed after driving a few
minutes message.
X Press the : button.
The Use Current Pressures As New
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the a button.
The Tire Press. Monitor Restarted
message appears in the multifunction
display.
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. 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
permissible vehicle load. It also contains
details of the tire sizes and
corresponding pressures for tires
installed 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. :
B-pillar, driver's side Loading the vehicle
537
Wheels and tires Z

Maximum permissible gross vehicle
weight rating
X
The Tire and Loading Information placard
gives you details on maximum permissible
gross vehicle weight rating : : "The gross
weight of occupants and luggage must
never exceed XXX kilograms or XXX
pounds."
The gross weight of all vehicle occupants,
load and luggage must not exceed the
specified value.
i The specifications shown on the Tire and
Loading Information placard in the
illustration are examples. The maximum
permissible 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 Information placard. Number of seats Maximum
number of seats
: determines
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
illustration 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
Loading 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".
X
Step 1: Locate the statement "The
combined 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
kilograms 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 pound 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
capacity calculated in step 4. 538
Loading the vehicle
Wheels and tires

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 use a maximum load 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 537).
The higher the weight of all the occupants, the
smaller the maximum load for luggage.
Step 1 Example
1 Example 2
Combined
maximum
weight of
occupants
and cargo
(data
from

the
Tire and
Loading
Information
placard) 1500 lbs
(680 kg) 1500 lbs
(680 kg)
Step 2
Example
1 Example 2
Number of
people in the
vehicle
(driver
and
occupants) 1 2
Weight of the
occupants
Occupant
1: 175 lbs
(80 kg) Occupant
1: 175 lbs
(80 kg)
Occupant
2: 195 lbs
(88 kg)
Gross weight
of all
occupants
175 lbs
(80 kg) 370 lbs
(168 kg) Step 3
Example 1 Example 2
Permissible
load
(maximum
gross vehicle
weight rating
from the Tire
and Loading
Information
placard minus
the gross
weight of all
occupants)
1500 lbs
(680 kg)
Ò
175 lbs
(80 kg) =
1325 lbs
(600 kg) 1500 lbs
(680 kg)
Ò
370 lbs
(168 kg) =
1130 lbs
(512 kg) Vehicle identification plate
Even if you have calculated the total load
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 537).
Permissible gross vehicle weight: the
gross weight of the vehicle, all passengers
and the load must not exceed the permissible
gross vehicle weight.
Gross axle weight rating: the maximum
permissible weight that can be carried by one
axle (front or rear axle).
To ensure that your vehicle does not exceed
the maximum permissible values (gross
vehicle weight and maximum gross axle
weight rating), have your loaded vehicle
(including driver, occupants and the load)
weighed on a suitable vehicle weighbridge. Loading the vehicle
539
Wheels and tires Z

All about wheels and tires
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: treadwear
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.
Where applicable, the tire grading
information can be found on the tire sidewall
between the tread shoulder and maximum
tire width.
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,
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.
! 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 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
freezing point.
Mercedes-Benz recommends a minimum
tread depth of ã in (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (Y page 527). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than 540
All about wheels and tires
Wheels and tires

on surfaces that are not icy or covered with
snow. Take appropriate care when driving.
Further information on winter tires (M+S
tires) (Y page 528).
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 :
Uniform Tire Quality Grading Standard
(Y page 545)
; DOT, Tire Identification Number
(Y page 544)
= Maximum tire load ( Y page 544)
? Maximum tire pressure (Y page 532)
A Manufacturer
B Tire material ( Y page 545)
C Tire size designation, load-bearing
capacity and speed index (
Y

page 541)
D Load index ( Y page 544)
E Tire name
The markings described above are on the tire
in addition to the tire name (sales
designation) and the manufacturer's name.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating G
WARNING
Exceeding the stated tire load-bearing
capacity and the approved maximum speed
could lead

to tire damage or the tire bursting.
There is a risk of accident. All about wheels and tires
541
Wheels and tires
Z

Therefore, only use tire types and sizes
approved
for
your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle. :
Tire width
; Nominal aspect ratio in %
= Tire code
? Rim diameter
A Load bearing index
B 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
description (as shown above): these are
passenger vehicle tires according to
European manufacturing 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.
manufacturing 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 width : shows the nominal
tire width in millimeters.
Height-width ratio: aspect ratio ; is the
size ratio between the tire height and tire
width and is shown in percent. The aspect ratio is calculated by dividing the tire width by
the tire height.
Tire
code:
tire

code = specifies the tire type.
"R" represents radial tires; "D" represents
diagonal tires; "B" represents diagonal radial
tires.
Optionally, tires with a maximum speed of
over 149 mph (240 km/h) may have "ZR" in
the size description, depending on the
manufacturer (e.g. 245/40 ZR 18).
Rim diameter: rim diameter ? is the
diameter of the bead seat, not the diameter
of the rim flange. The rim diameter is
specified in inches (in).
Load-bearing index: load-bearing index A
is a numerical code that specifies the
maximum load-bearing capacity of a tire.
Do not overload the tires by exceeding the
specified load limit. The maximum
permissible load can be found on the
vehicle's Tire and Loading Information
placard on the B-pillar on the driver's side
(Y page 537).
Example:
The load bearing index 91 indicates a
maximum load of 1356 lb (615 kg) that the
tires can bear. For further information on the
maximum tire load in kilograms and pounds,
see ( Y page 544).
For further information on the load bearing
index, see "Load index" ( Y page 544).
Speed rating: speed rating B specifies the
approved maximum speed of the tire.
i Tire data is vehicle-specific and may
deviate from the data in the example.
Regardless of the speed rating, always
observe the speed limits. Drive carefully and
adapt your driving style to the traffic
conditions. 542
All about wheels and tires
Wheels and tires