2008 SATURN ASTRA light

Fuses Usage
16Front Passenger Seat
Detection Sensor
17Tire Pressure
Monitoring
System (TPMS)/
Rain Sensor/Inside
Rearview Mirror
18 Interior Lights
21 Outside Mirror Heating
22 Sunroof
23 Rear Power Window
24Diagnostic Link
Connector
29Accessory Power
Outlet (APO)
34 Sunroof
38 Door Locks
39 Seat Heating Driver
40Seat Heating Front
PassengerTires
Your new vehicle comes with
high-quality tires made by
a leading tire manufacturer.
If you ever have questions about
the tire warranty and where to
obtain service, see the “Limited
Warranty, Maintenance and
Owner Assistance Information”
manual for details.
{CAUTION
Poorly maintained and
improperly used tires are
dangerous.
Overloading your tires can
cause overheating as a
result of too much exing.
You could have an air-out
and a serious accident.
SeeLoading the Vehicle
on page 8-30.
(Continued)
CAUTION (Continued)
Underinated tires pose
the same danger as
overloaded tires.
The resulting accident
could cause serious
injury. Check all tires
frequently to maintain the
recommended pressure.
Tire pressure should be
checked when your tires
are cold. SeeInflation - Tire
Pressure on page 9-46.
Overinated tires are more
likely to be cut, punctured,
or broken by a sudden
impact — such as when
you hit a pothole. Keep
tires at the recommended
pressure.
(Continued)
9-38 Vehicle Service and Care
ProCarManuals.com

DOT Markings:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) motor vehicle safety
standards. The DOT code
includes the Tire Identication
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and date
of production.
GVWR
:Gross Vehicle Weight
Rating. SeeLoading the Vehicle
on page 8-30.
GAWR FRT
:Gross Axle Weight
Rating for the front axle.
SeeLoading the Vehicle on
page 8-30.
GAWR RR
:Gross Axle Weight
Rating for the rear axle.
SeeLoading the Vehicle on
page 8-30.Intended Outboard Sidewall
:The side of an asymmetrical tire,
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric
unit for air pressure.
Light Truck (LT-Metric) Tire
:A tire used on light duty trucks
and some multipurpose
passenger vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.
Maximum Ination
Pressure
:The maximum air
pressure to which a cold tire
can be inated. The maximum
air pressure is molded onto
the sidewall.
Maximum Load Rating
:The load rating for a tire at the
maximum permissible ination
pressure for that tire.Maximum Loaded Vehicle
Weight
:The sum of curb
weight, accessory weight,
vehicle capacity weight, and
production options weight.
Normal Occupant Weight
:The
number of occupants a vehicle
is designed to seat multiplied by
150 lbs (68 kg). SeeLoading
the Vehicle on page 8-30.
Occupant Distribution
:Designated seating positions.
Outward Facing Sidewall
:The side of an asymmetrical tire
that has a particular side that
faces outward when mounted on
a vehicle. The side of the tire
that contains a whitewall,
bears white lettering, or bears
manufacturer, brand, and/or
model name molding that
is higher or deeper than the
same moldings on the
other sidewall of the tire.
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Passenger (P-Metric) Tire:A tire used on passenger cars
and some light duty trucks
and multipurpose vehicles.
Recommended Ination
Pressure
:Vehicle
manufacturer’s recommended
tire ination pressure as shown
on the tire placard. See
Inflation - Tire Pressure on
page 9-46andLoading
the Vehicle on page 8-30.
Radial Ply Tire
:A pneumatic
tire in which the ply cords that
extend to the beads are laid
at 90 degrees to the centerline
of the tread.
Rim
:A metal support for a tire
and upon which the tire beads
are seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate.Traction
:The friction between
the tire and the road surface.
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 inch
(1.6 mm) of tread remains.
SeeWhen It Is Time for New
Tires on page 9-53.
UTQGS (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 government testing
procedures. The ratings are
molded into the sidewall of the
tire. SeeUniform Tire Quality
Grading on page 9-56.Vehicle Capacity Weight
:The number of designated
seating positions multiplied
by 150 lbs (68 kg) plus the
rated cargo load. SeeLoading
the Vehicle on page 8-30.
Vehicle Maximum Load on
the Tire
:Load on an individual
tire due to curb weight,
accessory weight, occupant
weight, and cargo weight.
Vehicle Placard
:A label
permanently attached to a
vehicle showing the vehicle’s
capacity weight and the original
equipment tire size and
recommended ination pressure.
See “Tire and Loading
Information Label” under
Loading the Vehicle on
page 8-30.
Vehicle Service and Care 9-45
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Tire Pressure Monitor
Operation
The Tire Pressure Monitor System
(TPMS) is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and
wheel assembly, excluding the
spare tire. The TPMS sensors
monitor the air pressure in the
vehicle’s tires and transmit tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning
light located in the instrument
panel cluster.The low tire pressure warning light
comes on at each ignition cycle
until the tires are inated to
the correct ination pressure.
The low tire pressure warning light
may come on in cool weather
when the vehicle is rst started, and
then turn off as you start to drive.
This could be an early indicator that
the air pressure in the tire(s) are
getting low and need to be inated
to the proper pressure.
You must begin driving before the
TPMS system is operational.
TPMS sensors need to be installed
onto the full-size tire and wheel
assemblies, and the tires adjusted
to the manufacturers’ recommended
tire pressure amount.
A Tire and Load Information label is
attached to the vehicle, and shows
the size of the vehicle’s original
equipment tires and the correct
ination pressure for the tires when
they are cold. SeeLoading the
Vehicle on page 8-30, for anexample of the Tire and Load
Information label and its location on
the vehicle. Also seeInflation - Tire
Pressure on page 9-46.
The vehicle’s TPMS can warn you
about a low tire pressure condition
but it does not replace normal tire
maintenance. SeeTire Inspection
and Rotation on page 9-51andTires
on page 9-38.
Notice:Liquid tire sealants
could damage the Tire Pressure
Monitor System (TPMS) sensors.
Sensor damage caused by
using a tire sealant is not covered
by your warranty. Do not use
liquid tire sealants.
Each TPMS sensor has a unique
identication code. Any time
you replace one or more of the
TPMS sensors or rotate the
vehicle’s tires, the identication
codes are automatically learned by
the TPMS. This occurs within a
few moments of driving the vehicle
over 19 mph (31 km/h).
9-50 Vehicle Service and Care
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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 9-53.
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 9-58
for more information.
Vehicle Service and Care 9-51
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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. 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 9-60for 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 9-46and
Loading the Vehicle on
page 8-30.
9-52 Vehicle Service and Care
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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 moldedon 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.
9-56 Vehicle Service and Care
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6. Raise the vehicle by turning the
jack handle clockwise. Raise the
vehicle far enough off the
ground so there is enough room
for the compact spare tire to
t under the vehicle.
7. Remove all of the wheel bolts.
{CAUTION
Rust or dirt on a wheel, or on
the parts to which it is
fastened, can make wheel bolts
become loose after time. The
wheel could come off and
cause an accident. When you
change a wheel, remove any
rust or dirt from places where
the wheel attaches to the
vehicle. In an emergency, you
can use a cloth or a paper
towel to do this; but be sure to
use a scraper or wire brush
later, if needed, to get all the
rust or dirt off. SeeChanging a
Flat Tire on page 9-60.8. Remove any rust or dirt from the
wheel bolts, mounting surfaces
and spare wheel.
Installing wheels with a good
metal-to-metal contact at
the mounting surface is
necessary to prevent the wheel
bolts from becoming loose.
To prevent corrosion or rust
build-up, apply a light coat of
wheel bearing grease to the
wheel hub center and to the
cone-shaped surface of each
wheel bolt at every wheel change.
9-64 Vehicle Service and Care
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