2012 MERCEDES-BENZ SL-CLASS ROADSTER spare tire

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 telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
sequence will continue upon subsequent
vehicle start-ups 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 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 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.
iUSA only:
If a condition causing the TPMS to
malfunction develops, it may take up to
10 minutes for the system to signal a
malfunction using the TPMS telltale
flashing and illumination sequence.
The telltale extinguishes after a few
minutes driving if the malfunction has been
corrected.
Tire pressure inquiries are made using the
multifunction display. The current tire
inflation pressure for each tire appears in the
multifunction display after a few minutes of
driving.
iPossible differences between the
readings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and the
vehicle’s control system can occur. The tire
pressure displayed by the control system
apply to sea level. In high-altitude
locations, the reading on a tire pressure
gauge will be higher than the reading issued
by the vehicle’s control system. Do not
reduce the tire inflation pressure under
such circumstances.
XSwitch on the ignition.XPress button V or U on the
multifunction steering wheel repeatedly
until the standard display appears in the
multifunction display (Y page 116).
XPress button & or * until the current
inflation pressure for each tire appears in
the multifunction display.
Example illustration
When the vehicle has been parked for longer
than 20 minutes, the message Tire
pressure displayed after driving
for a few minutes. appears in the
multifunction display.
The TPMS recognizes new wheels or sensors
automatically after the learn-in phase. As long
as the tire inflation pressure values cannot be
allocated to the individual wheels, the
message Tire Pressure Monitor Active
Menu: R-Button appears. Despite this
message, the tire inflation pressure values
are monitored already.
iWith a spare wheel mounted, the system
may still indicate the tire inflation pressure
of the removed road wheel for some
minutes. If this happens, keep in mind that
the indicated value where the spare wheel
is mounted does not reflect the actual
spare tire inflation pressure.
iOperating radio transmission equipment
(e.g. wireless headsets, two-way radios) in
or near the vehicle could cause the TPMS
to malfunction.
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Maximum tire loadGWarning!
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.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
The maximum tire load rating : is the
maximum weight the tires are designed to
support.
For more information on tire load rating, see
(Y page 202).
For information on calculating total and cargo
load capacities, see (Y page 195).
Direction of rotation
Unidirectional tires offer added advantages,
such as better hydroplaning performance. To
benefit, however, you must make sure the
tires rotate in the direction specified.
An arrow on the sidewall indicates the
intended direction of rotation of the tire.
Spare wheels may be mounted against the
direction of rotation (spinning) even with a
unidirectional tire for temporary use only until
the regular drive wheel has been repaired or
replaced. Always observe and follow
applicable temporary use restrictions and
speed limitations indicated on the spare
wheel.
MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires.
You may only use the MOExtended system in
conjunction with the Advanced TPMS
(Y page 190).
For information on driving in case of pressure
loss in one or more tires (emergency mode),
see the “Practical hints” section
(Y page 283).
Tire care and maintenance
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.
Check the tire inflation pressure at least once
a month. For more information on checking
tire inflation pressure, see “Recommended
tire inflation pressure” (Y page 187).
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Tire inspection
Every time you check the tire inflation
pressure, you should also inspect your tires
for the following:
Rexcessive treadwear (Y page 198)
Rcord or fabric showing through the tire’s
rubber
Rbumps, bulges, cuts, cracks or splits in the
tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation. Spare
tires will age and become worn over time even
if never used, and thus should be inspected
and replaced when necessary.
Life of tire
GWarning!
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.
The service life of a tire is dependent upon
varying factors including but not limited to:
RDriving style
RTire inflation pressure
RDistance driven
Tread depth
GWarning!
Although the applicable federal motor vehicle
safety laws consider a tire to be worn when
the treadwear 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.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.
Do not allow your tires to wear down too far.
Adhesion properties on wet roads are sharply
reduced at tread depths of less than 1/8 in
(3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six places
on the tread circumference and become
visible at a tread depth of approximately1/16 in (1.6 mm), at which point the tire is
considered worn and should be replaced.
The recommended minimum tire tread depth
for summer tires is 1/8 in (3 mm). The
recommended minimum tire tread depth for
winter tires is 1/6 in (4 mm).
Treadwear indicator : appears as a solid
band across the tread.
Storing tires
! Keep unmounted tires in a cool, dry place
with as little exposure to light as possible.
Protect tires from contact with oil, grease
and fuels.
Cleaning tires
! Never use a round nozzle to power wash
tires. The intense jet of water can result in
damage to the tire.
Always replace a damaged tire.
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Following are some explanations for the
markings on your vehicle’s tires::Uniform Tire Quality Grading Standards
(Y page 199)
;DOT, Tire Identification Number
(Y page 204)
=Maximum tire load (Y page 197)?Maximum tire inflation pressure
(Y page 193)
AManufacturerBTire ply material (Y page 205)CTire size designation, load and speed
rating (Y page 201)
DLoad identification (Y page 204)ETire name
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
For more information, see “Rims and tires”
(Y page 299).
Tire size designation, load and speed
rating:Tire width;Aspect ratio in %=Radial tire code?Rim diameterALoad index BSpeed symbol
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and
may vary from data shown in above
illustration.
General: Depending on the design standards
used, the tire size molded into the sidewall
may have no letter or a letter preceding the
tire size designation.
No letter preceding the size designation (as
illustrated above): Passenger car tire based
on European design standards.
Letter “P” preceding the size designation:
Passenger car tire based on U.S. design
standards.
Letter “LT” preceding the size designation:
Light Truck tire based on U.S. design
standards.
Letter “T” preceding the size designation:
Temporary spare tires which are high
pressure compact spares designed for
temporary emergency use only.
Tire width
Tire width : indicates the nominal tire width
in millimeters.
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GAWR (Gross Axle Weight Rating)
The GAWR is the maximum permissible axle
weight. The gross vehicle weight on each axle
must never exceed the GAWR for the front
and rear axle indicated on the certification
label located on the driver’s door B-pillar.
GVW (Gross Vehicle Weight)
The GVW comprises the weight of the vehicle
including fuel, tools, spare wheel, installed
accessories, passengers and cargo and, if
applicable, trailer tongue load. The GVW must
never exceed the GVWR indicated on the
certification label located on the driver’s door
B-pillar.
GVWR (Gross Vehicle Weight Rating)
This is the maximum permissible vehicle
weight of the fully loaded vehicle (weight of
the vehicle including all options, passengers,
fuel, and cargo and, if applicable, trailer
tongue load). It is indicated on the
certification label located on the driver’s door
B-pillar.
Kilopascal (kPa)
Metric unit for air pressure. There are 6.9 kPa
to 1 psi; another metric unit for air pressure
is bar. There are 100 kilopascals (kPa) to
1 bar.
Load index
Numerical code associated with the
maximum load a tire can support.
Maximum load rating
The maximum load in kilograms and pounds
that can be carried by the tire.
Maximum loaded vehicle weight
The sum of curb weight, accessory weight,
total load limit, and production options
weight.
Maximum permissible tire inflation
pressure
This number is the greatest amount of air
pressure that should ever be put in the tire.
Normal occupant weight
The number of occupants the vehicle is
designed to seat, multiplied by 68 kilograms
(150 lb).
Occupant distribution
The distribution of occupants in a vehicle at
their designated seating positions.
Production options weight
The combined weight of those installed
regular production options weighing over
5 lbs (2.3 kilograms) in excess of those
standard items which they replace, not
previously considered in curb weight or
accessory weight, including heavy duty
brakes, ride levelers, roof rack, heavy duty
battery, and special trim.
PSI (Pounds per square inch)
A standard unit of measure for air pressure.
Recommended tire inflation pressure
The recommended tire inflation pressure for
normal driving conditions is listed on the Tire
and Loading Information placard located on
the driver’s door B-pillar. It provides best
handling, tread life and riding comfort.
Supplemental information pertaining to
special driving situations can be found on the
tire inflation pressure label on the inside of
the fuel filler flap.
Rim
A metal support for a tire or a tire and tube
assembly upon which the tire beads are
seated.
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Sidewall
The portion of a tire between the tread and
the bead.
TIN (Tire Identification Number)
Unique identifier which facilitates efforts by
tire manufacturers to notify purchasers in
recall situations or other safety matters
concerning tires and gives purchasers the
means to easily identify such tires. The TIN is
comprised of “Manufacturer’s identification
mark”, “Tire size”, “Tire type code” and “Date
of manufacture”.
Tire ply composition and material used
This indicates the number of plies or the
number of layers of rubber-coated fabric in
the tire tread and sidewall. Tire
manufacturers also must indicate the ply
materials in the tire and sidewall, which
include steel, nylon, polyester, and others.
Tire speed rating
Part of tire designation (speed symbol);
indicates the speed range for which a tire is
approved.
Total load limit
Rated cargo and luggage load plus
68 kilograms (150 lb) times the vehicle’s
designated seating capacity.
Traction
The adhesive friction of a tire on a surface on
which it moves. The amount of grip provided.
Tread
The portion of a tire that comes into contact
with the road.
Treadwear indicators
Narrow bands, sometimes called “wear bars”
that show across the tread of a tire when only
1 / 16 in (1.6 mm) of tread remains.
Uniform Tire Quality Grading Standards
A tire information system that provides
consumers with ratings for a tire’s traction,
temperature and treadwear. Ratings are
determined by tire manufacturers using U.S.
government testing procedures. The ratings
are molded into the sidewall of the tire.
Vehicle maximum load on the tire
Load on an individual tire that is determined
by distributing to each axle its share of the
maximum loaded vehicle weight and dividing
it by two.
Winter driving
General information
Have your vehicle winterized at an authorized
Mercedes-Benz Center.
Winter tires
GWarning!
Winter tires with a tread depth of less than
1 / 6 in (4 mm) must be replaced. They are no
longer suitable for winter operation.
GWarning!
If you use your spare wheel when winter tires
are fitted on the other wheels, be aware that
the difference in tire characteristics may very
well impair turning stability and that overall
driving stability may be reduced. Adapt your
driving style accordingly.
Have the spare wheel replaced by a regular
road wheel with a winter tire at the nearest
authorized Mercedes-Benz Center.
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Always use winter tires at temperatures
below 45‡ (7†) and whenever wintry road
conditions prevail. Not all M+S rated tires
provide special winter performance. Make
sure the tires you use show the mountain/
snowflake imarking on the tire sidewall.
These tires meet specific snow traction
performance requirements of the Rubber
Manufacturers Association (RMA) and the
Rubber Association of Canada (RAC) and
have been designed specifically for use in
snow conditions. Use of winter tires is the
only way to achieve the maximum
effectiveness of your vehicle’s driving safety
systems such as the ABS and the ESP ®
in
winter operation.
For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
For information on winter tires for your
vehicle model, see the “Technical data”
section ( Y page 299).
Always observe the speed rating of the winter
tires installed on your vehicle.
After installing winter tires:XCheck the tire inflation pressure and adjust
it if necessary ( Y page 189).XRestart the Advanced Tire Pressure
Monitoring System ( Y page 190).
Snow chains
! When driving with snow chains, always
select setting 1 of the vehicle level control.
Other settings may result in damage to your
vehicle.
! Some tire sizes do not leave adequate
clearance for snow chains. To help avoid
serious damage to your vehicle or tires,
make sure the use of snow chains is
permissible as specified in the “Technical
data” section of this Operator’s Manual.
Snow chains should only be driven on snow-
covered roads at speeds not to exceed
30 mph (50 km/h). Remove chains as soon
as possible when driving on roads without
snow.
Observe the following guidelines when using
snow chains:
R Use of snow chains is not permissible with
all wheel/tire combinations ( Y page 299).
R Use snow chains in pairs and on rear
wheels only. Follow the manufacturer’s
mounting instructions.
! If snow chains are mounted to the front
wheels, they may scrape against the body
or axle components. The tires or the vehicle
could be damaged as a result.
R Only use snow chains that are approved by
Mercedes-Benz. Any authorized Mercedes-
Benz Center will be glad to advise you on
this subject.
R Use of snow chains may be prohibited
depending on location. Always check local
and state laws before installing snow
chains.
R Do not use snow chains on the spare wheel.
i When driving with snow chains, you may
wish to switch off the ESP ®
(Y page 56)
before setting the vehicle in motion. This
will improve the vehicle’s traction.
Winter driving instructions
GWarning!
If the vehicle becomes stuck in snow, make
sure snow is kept clear of the exhaust pipe
and from around the vehicle with the engine
running. Otherwise, deadly carbon monoxide
(CO) gases may enter vehicle interior
resulting in unconsciousness and death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
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XTo access jack and wheel wrench:
Remove storage well casing =.
XRemove the spare wheel (Y page 225).AJackBWheel wrench
Jack
GWarning!
Only use the jack supplied with your vehicle
to lift the vehicle briefly for wheel changes. If
you use the jack for any other purpose, you or
others could be injured, as the jack is
designed only for the purpose of changing a
wheel.
When using the jack, observe the safety notes
in the “Mounting the spare wheel” section and
the notes on the jack.
Spare wheel
GObserve Safety notes, see page 276.
The spare wheel is located in the space
underneath the trunk floor.
XRemoving: Open the trunk (Y page 73).XLift the trunk floor.XRemove the storage well casing
(Y page 224).:Spare wheel;Tensioning strap18=Retaining screw?Storage well casing baseXRemove storage well casing base ?.XRemove retaining screw = by turning it
counterclockwise.
XRemove spare wheel :.
For information on mounting the spare wheel,
see “Flat tire” (Y page 276).
Storing the spare wheel after use
If you wish to store the spare wheel after use,
carry out the following steps. Otherwise, the
spare wheel may not fit into the spare wheel
well.
! Make sure the spare wheel is dry before
storing it.
XUnscrew the valve cap from the valve of the
collapsible tire.
XUnscrew the valve insert from the valve
using the valve extractor integrated in the
valve cap.
XAllow the air to escape.
iIt may take a few minutes for the
collapsible tire to deflate completely.
XUse the valve extractor integrated in the
valve cap to screw the valve insert back into
the valve.
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