2009 SATURN ASTRA service

TPMS Malfunction Light
The TPMS will not function properly
if one or more of the TPMS
sensors are missing or inoperable.
When the system detects a
malfunction, the low tire warning
light ashes for about one minute
and then stays on for the remainder
of the ignition cycle. Some of the
conditions that can cause the
malfunction light to come on are:
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The TPMS malfunction
light and DIC message should go
off once you re-install the road tire
containing the TPMS sensor.
One or more TPMS sensors are
missing or damaged. The TPMS
malfunction light should go off
after the TPMS sensors are
installed and the vehicle is
driven for a few moments over
19 mph (31 km/h). See your
dealer/retailer for service.
Replacement tires or wheels do
not match the vehicle’s original
equipment tires or wheels. Tires
and wheels other than those
recommended for the vehicle
could prevent the TPMS from
functioning properly. SeeBuying
New Tires on page 9-54.
Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning it
cannot detect or signal a low tire
condition. See your dealer/retailer for
service if the TPMS malfunction light
comes on and stays on.
Tire Inspection and
Rotation
Inspect tires regularly for signs of
wear or damage. Also inspect the
spare tire. For more information
on tire inspection, seeWhen It Is
Time for New Tires on page 9-54.
Rotating vehicle tires helps them
to wear evenly and keeps the
vehicle performing like it
did when tires were new.
Rotate the tires and check
wheel alignment approximately
every 5,000 to 8,000 miles
(8 000 to 13 000 km) or when
unusual tire wear is noted.
See “Scheduled Maintenance”
in the Index of the “Limited
Warranty, Maintenance
and Owner Assistance
Information” manual for more
information. Also check the
wheels for damage, seeWheel
Replacement on page 9-59
for more information.
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Use this pattern when rotating
the vehicle tires. Do not include
the compact spare tire in the
tire rotation.
{CAUTION
Rust or dirt on a wheel, or on
the parts to which it is
fastened, can make wheel
bolts become loose after time.
(Continued)
CAUTION (Continued)
The wheel could come off and
cause a crash. When you
change a wheel, remove any
rust or dirt from places where
the wheel attaches to the
vehicle using a scraper or
wire brush.
Installing wheels with a good
metal-to-metal contact at
the mounting surfaces is
necessary to prevent wheel
bolts from becoming loose.
To prevent corrosion or
rust build-up, lightly coat the
wheel hub center and the
cone-shaped surface of each
wheel bolt with wheel bearing
grease, after a wheel change.SeeChanging a Flat Tire on
page 9-61for information
on installing the tire and wheel
assembly. Also see “Wheel
Bolt Torque” underCapacities
and Specifications on page 10-2.
Adjust the front and rear
tires to the recommended
cold tire ination pressure
shown on the Tire and
Loading Information label.
SeeInflation - Tire Pressure
on page 9-47andLoading the
Vehicle on page 8-30.
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When It Is Time for
New Tires
Various factors, such as
maintenance, temperatures, driving
speeds, vehicle loading, and
road conditions inuence when you
need new tires.
One way to tell when it is time for
new tires is to check the treadwear
indicators, which will appear
when the tires have only 1/16 inch
(1.6 mm) or less of tread remaining.You need new tires if any of the
following statements are true:You can see the indicators at
three or more places around
the tire.
You can see cord or fabric
showing through the tire’s rubber.
The tread or sidewall is cracked,
cut, or snagged deep enough to
show cord or fabric.
The tire has a bump, bulge,
or split.
The tire has a puncture, cut, or
other damage that cannot be
repaired well because of the size
or location of the damage.
The rubber in tires degrades over
time, even if they are not being
used. This is also true for the spare
tire, if the vehicle has one. Multiple
conditions affect how fast this
aging takes place, including
temperatures, loading conditions,
and ination pressure maintenance.With proper care and maintenance
tires typically wear out before
they degrade due to age. If you are
unsure about the need to replace
the tires as they get older, consult
the tire manufacturer for more
information.
Buying New Tires
GM has developed and matched
specic tires for your vehicle.
The original equipment tires installed
on your vehicle, when it was new,
were designed to meet General
Motors Tire Performance Criteria
Specication (TPC Spec) system
rating. If you need replacement tires,
GM strongly recommends that
you get tires with the same TPC
Spec rating. This way, your vehicle
will continue to have tires that
are designed to give the same
performance and vehicle safety,
during normal use, as the
original tires.
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GM’s exclusive TPC Spec system
considers over a dozen critical
specications that impact the overall
performance of your vehicle,
including brake system performance,
ride and handling, traction control,
and tire pressure monitoring
performance. GM’s TPC Spec
number is molded onto the tire’s
sidewall near the tire size. If the tires
have an all-season tread design,
the TPC Spec number will be
followed by an MS for mud and
snow. SeeTire Sidewall Labeling on
page 9-42for additional information.
GM recommends replacing tires
in sets of four. This is because
uniform tread depth on all tires will
help keep your vehicle performing
most like it did when the tires
were new. Replacing less than a
full set of tires can affect the braking
and handling performance of your
vehicle. SeeTire Inspection
and Rotation on page 9-52for
information on proper tire rotation.{CAUTION
Mixing tires could cause you
to lose control while driving.
If you mix tires of different
sizes, brands, or types
(radial and bias-belted tires),
the vehicle may not handle
properly, and you could have
a crash. Using tires of different
sizes, brands, or types may
also cause damage to the
vehicle. Be sure to use the
correct size, brand, and type
of tires on all wheels. It is all
right to drive with the compact
spare temporarily, as it was
developed for use on the
vehicle. SeeCompact Spare
Tire on page 9-68.{CAUTION
If you use bias-ply tires on
the vehicle, the wheel rim
anges could develop cracks
after many miles of driving.
A tire and/or wheel could fail
suddenly, causing a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If you must replace your vehicle’s
tires with those that do not have
a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction type (radial and
bias-belted tires) as your vehicle’s
original tires.
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Vehicles that have a tire pressure
monitoring system could give
an inaccurate low-pressure warning
if non-TPC Spec rated tires are
installed on your vehicle. Non-TPC
Spec rated tires may give a
low-pressure warning that is higher
or lower than the proper warning
level you would get with TPC Spec
rated tires. SeeTire Pressure
Monitor System on page 9-49.
Your vehicle’s original equipment
tires are listed on the Tire and
Loading Information Label. See
Loading the Vehicle on page 8-30,
for more information about the
Tire and Loading Information Label
and its location on your vehicle.Different Size Tires and
Wheels
If you add wheels or tires that are a
different size than your original
equipment wheels and tires,
this may affect the way your vehicle
performs, including its braking,
ride and handling characteristics,
stability, and resistance to rollover.
Additionally, if your vehicle has
electronic systems such as, anti-lock
brakes, traction control, and
stability control, the performance of
these systems can be affected.
{CAUTION
If you add different sized
wheels, your vehicle may not
provide an acceptable level of
performance and safety if tires not
recommended for those wheels
are selected. You may increase
the chance that you will crash and
suffer serious injury. Only use
Saturn specic wheel and tire
systems developed for your
vehicle, and have them properly
installed by a Saturn certied
technician.
SeeBuying New Tires on page 9-54
andAccessories and Modifications
on page 9-3for additional
information.
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Uniform Tire Quality
Grading
Quality grades can be found
where applicable on the
tire sidewall between tread
shoulder and maximum section
width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates
to the system developed by
the United States National
Highway Traffic Safety
Administration (NHTSA),
which grades tires by treadwear,
traction, and temperature
performance. This applies
only to vehicles sold in the
United States. The grades are
molded on the sidewalls of
most passenger car tires.
The Uniform Tire Quality
Grading (UTQG) system
does not apply to deep tread,winter-type snow tires,
space-saver, or temporary use
spare tires, tires with nominal rim
diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary
with respect to these grades,
they must also conform to
federal safety requirements and
additional General Motors
Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a
comparative rating based on
the wear rate of the tire
when tested under controlled
conditions on a specied
government test course.For example, a tire graded 150
would wear one and a half (1.5)
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 signicantly from
the norm due to variations in
driving habits, service practices,
and differences in road
characteristics and climate.
Traction – AA, A, B, C
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
specied government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
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Temperature – A, B, C
The temperature grades are
A (the highest), B, and C,
representing the tire’s resistance
to the generation of heat and
its ability to dissipate heat
when tested under controlled
conditions on a specied 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. It should benoted that the temperature grade
for this tire is established for a tire
that is properly inated and not
overloaded. Excessive speed,
underination, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
{WARNING
The temperature grade for this
tire is established for a tire
that is properly inated and
not overloaded. Excessive
speed, underination, or
excessive loading, either
separately or in combination,
can cause heat buildup and
possible tire failure.
Wheel Alignment and
Tire Balance
The tires and wheels on your
vehicle were aligned and balanced
carefully at the factory to give
you the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
will not be necessary on a regular
basis. However, if you notice
unusual tire wear or your vehicle
pulling to one side or the other, the
alignment might need to be
checked. If you notice your vehicle
vibrating when driving on a
smooth road, the tires and wheels
might need to be rebalanced.
See your dealer/retailer for proper
diagnosis.
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Wheel Replacement
Replace any wheel that is bent,
cracked or badly rusted or corroded.
If the wheel bolts keep coming
loose, the wheel and wheel bolts
should be replaced. If the wheel
leaks air, replace it (except some
aluminum wheels, which can
sometimes be repaired). See your
dealer/retailer if any of these
conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the
one it replaces.
If you need to replace any of the
wheels or wheel bolts, replace them
only with new GM original equipment
parts. This way, you will be sure to
have the right wheel and wheel bolts
for the vehicle.{CAUTION
Using the wrong replacement
wheels or wheel bolts on your
vehicle can be dangerous. It could
affect the braking and handling of
the vehicle, make the tires lose air
and make you lose control of
the vehicle. You could have a
collision in which you or others
could be injured. Always use the
correct wheel and wheel bolts for
replacement.
Notice:The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration,
headlamp aim, bumper height,
vehicle ground clearance, and tire
or tire chain clearance to the
body and chassis.
SeeChanging a Flat Tire on
page 9-61for more information.
Used Replacement Wheels
{CAUTION
Putting a used wheel on the
vehicle is dangerous. You cannot
know how it has been used or
how far it has been driven.
It could fail suddenly and cause a
crash. If you have to replace a
wheel, use a new GM original
equipment wheel.
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