2008 SATURN ASTRA brake

Fuses Usage
8 Horn
10 Door Locks
13 Foglamps
14Windshield Wipers
(high speed)
15Windshield Wipers
(low speed)
16Antilock Brake System,
Brake Lamp Switch
17 Vacuum Pump
18 Starter
20 Air Conditioning Clutch
21Engine Control
Module (ECM)
(Main Relay)
22 ECM (Battery)
24 Fuel Pump/InjectorsFuses Usage
26ECM (Sensor and
Actuators)
27 Power Steering
28Automatic
Transmission (Battery)
29Automatic
Transmission (Ignition)
30 ECM (Ignition)
32 Brake Switch
34Steering Column
Module
35 Radio
36OnStar™ Module/
OnStar™ Interface
Module/DisplayRear Compartment Fuse
Block
To open the liftgate, SeeLiftgate on
page 2-6.
The rear compartment fuse block is
located on the left side of the
cargo area behind a cover.
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(D) Construction Code:A letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or
bias ply construction; and the
letter B means belted-bias
ply construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:These characters represent the
load range and speed rating
of the tire. The load index
represents the load carry
capacity a tire is certied to
carry. The load index can range
from 1 to 279. The speed
rating is the maximum speed a
tire is certied to carry a load.
Speed ratings range from A to Z.
Tire Terminology and
Denitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:This means
the combined weight of optional
accessories. Some examples
of optional accessories are,
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire’s height to its width.
Belt
:A rubber coated layer of
cords that is located between the
plies and the tread. Cords may
be made from steel or other
reinforcing materials.Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a
tire, measured in pounds
per square inch (psi) or
kilopascals (kPa) before a tire
has built up heat from driving.
SeeInflation - Tire Pressure on
page 9-46.
Curb Weight
:The weight of a
motor vehicle with standard
and optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
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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.
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 9-40for 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 9-51for
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 9-67.
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{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.
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 warninglevel you would get with TPC Spec
rated tires. SeeTire Pressure
Monitor System on page 9-48.
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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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 9-60for 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.
Tire Chains
{CAUTION
Do not use tire chains. There is
not enough clearance. Tire
chains used on a vehicle
without the proper amount of
clearance can cause damage to
the brakes, suspension or
other vehicle parts. The area
damaged by the tire chains
could cause you to lose control
of the vehicle and you or others
may be injured in a crash.
(Continued)
CAUTION (Continued)
Use another type of traction
device only if its manufacturer
recommends it for use on
the vehicle and tire size
combination and road
conditions. Follow that
manufacturer’s instructions.
To help avoid damage to the
vehicle, drive slowly, readjust
or remove the device if it is
contacting the vehicle, and do
not spin the vehicle’s wheels.
If you do nd traction devices
that will t, install them on the
front tires.
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Tire Changing
If a Tire Goes Flat
It is unusual for a tire to blowout
while you are driving, especially if
you maintain your vehicle’s tires
properly. If air goes out of a tire, it is
much more likely to leak out slowly.
But if you should ever have a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the at tire creates
a drag that pulls the vehicle toward
that side. Take your foot off the
accelerator pedal and grip the
steering wheel rmly. Steer to
maintain lane position, and then
gently brake to a stop well out of the
traffic lane.
A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction you
would use in a skid. In any rear
blowout remove your foot from the
accelerator pedal. Get the vehicle
under control by steering theway you want the vehicle to go.
It may be very bumpy and noisy, but
you can still steer. Gently brake to
a stop, well off the road if possible.
{CAUTION
Lifting a vehicle and getting
under it to do maintenance or
repairs is dangerous without the
appropriate safety equipment
and training. The jack provided
with your vehicle is designed
only for changing a at tire. If it
is used for anything else, you or
others could be badly injured or
killed if the vehicle slips off the
jack. Use the jack provided with
your vehicle only for changing a
at tire.
If a tire goes at, the next part
shows how to use the jacking
equipment to change a at tire
safely.
Changing a Flat Tire
If a tire goes at, avoid further tire
and wheel damage by driving slowly
to a level place. Turn on the
hazard warning ashers.
{CAUTION
Changing a tire can be
dangerous. The vehicle can slip
off the jack and roll over or fall
on you or other people. You and
they could be badly injured or
even killed. Find a level place
to change your tire. To help
prevent the vehicle from
moving:
1. Set the parking brake
rmly.
2. Put an automatic
transmission shift lever in
P (Park), or shift a manual
transmission to 1 (First) or
R (Reverse).
(Continued)
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9. Place the compact spare tire on
the wheel-mounting surface.
10. Reinstall the wheel bolts with
the rounded end of the bolts
toward the wheel. Tighten each
bolt by hand until the wheel
is held against the hub.
11. Lower the vehicle by turning the
jack handle counterclockwise.
Lower the jack completely.12. Tighten the wheel bolts rmly
in a crisscross sequence,
as shown.
{CAUTION
Incorrect or improperly
tightened wheel bolts can
cause the wheel to come loose
and even come off. This could
lead to a crash. If you have to
(Continued)
CAUTION (Continued)
replace them, be sure to get
new original equipment wheel
bolts. Stop somewhere as
soon as you can and have the
bolts tightened with a torque
wrench to the proper torque
specication. SeeCapacities
and Specifications on
page 10-2for wheel bolt
torque specication.
Notice:Improperly tightened
wheel bolts can lead to brake
pulsation and rotor damage.
To avoid expensive brake repairs,
evenly tighten the wheel bolts
in the proper sequence and to
the proper torque specication.
SeeCapacities and Specifications
on page 10-2for the wheel bolt
torque specication.
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Jump Starting
If your battery has run down, try to
use another vehicle and some
jumper cables to start your vehicle.
Be sure to use the following steps
to do it safely.
{CAUTION
Batteries can hurt you. They
can be dangerous because:
They contain acid that can
burn you.
They contain gas that can
explode or ignite.
They contain enough
electricity to burn you.
If you do not follow these steps
exactly, some or all of these
things can hurt you.Notice:Ignoring these steps
could result in costly damage to
your vehicle that would not
be covered by your warranty.
Trying to start your vehicle by
pushing or pulling it will not work,
and it could damage your vehicle.
1. Check the other vehicle. It must
have a 12-volt battery with a
negative ground system.
Notice:If the other vehicle’s
system is not a 12-volt system
with a negative ground, both
vehicles can be damaged. Only
use vehicles with 12-volt systems
with negative grounds to jump
start your vehicle.
2. Get the vehicles close enough
so the jumper cables can
reach, but be sure the vehicles
are not touching each other.
If they are, it could cause
a ground connection you do not
want. You would not be able
to start your vehicle, and the bad
grounding could damage the
electrical systems.To avoid the possibility of the
vehicles rolling, set the parking
brake rmly on both vehicles
involved in the jump start
procedure. Put an automatic
transmission in PARK (P)
or a manual transmission in
NEUTRAL before setting
the parking brake.
Notice:If you leave your radio or
other accessories on during the
jump starting procedure, they
could be damaged. The repairs
would not be covered by your
warranty. Always turn off your
radio and other accessories when
jump starting your vehicle.
3. Turn off the ignition on both
vehicles. Unplug unnecessary
accessories plugged into the
cigarette lighter or the accessory
power outlet. Turn off the radio
and all lamps that are not needed.
This will avoid sparks and help
save both batteries. And it could
save the radio!
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