light CHEVROLET ASTRO 2003 Workshop Manual

If You Are Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you don’t want to spin your
wheels too fast. The method known as “rocking” can
help you get out when you’re stuck, but you must
use caution.
If you let your tires spin at high speed, they
can explode, and you or others could be
injured. And, the transmission or other parts of
the vehicle can overheat. That could cause an
engine compartment fire or other damage.
When you’re stuck, spin the wheels as little as
possible. Don’t spin the wheels above
25 mph
(55 km/h) as shown on the speedometer.
Notice: Spinning your wheels can destroy parts of
your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
For information about using tire chains on your
vehicle, see
Tire Chains on page 5-70.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between
REVERSE (R) and a forward gear,
spinning the wheels as little as possible. Release
the accelerator pedal while you shift, and press lightly
on the accelerator pedal when the transmission is
in gear. By slowly spinning your wheels in the forward
and reverse directions, you will cause a rocking
motion that may free your vehicle. If that doesn’t get
you out after a few tries, you may need to be towed out.
If you do need to be towed out, see “Towing Your
Vehicle” following.
4-28

Tow/Haul Mode
The tow/haul mode is a feature that assists when pulling
a heavy trailer. The purpose of the tow/haul mode is:
e to reduce the frequency of shifts when pulling a
heavy trailer.
to provide the same shift feel when pulling a heavy
trailer as when the vehicle is unloaded.
to reduce the need to change throttle position when
pulling a heavy trailer.
This feature is turned on or off by pressing a button on
the column shift lever. When the feature
is on, a
light on the instrument panel will illuminate to indicate
that the tow/haul mode has been selected.
See
Tow/Haul Mode Light on page 3-36. The tow/haul
mode is automatically turned
off each time the vehicle
is started.
The tow/haul mode is most effective when the vehicle
and trailer combined weight is at least
75% of the Gross
Vehicle Weight Rating (GVWR) and the maximum
trailer weight rating for the vehicle. The tow/haul
mode for hauling a heavy trailer is most
useful under the following conditions:
When driving through hilly terrain at speeds below
55 mph
(88 km/h).
When driving in low speed or stop and go traffic
below
55 mph (88 km/h).
When driving in parking lots.
Operating in the tow/haul mode when not pulling a
heavy trailer will not cause damage to the vehicle,
but you may experience reduced fuel economy
and undesirable petformance from the engine and
transmission. The tow/haul mode should be used only
when pulling a heavy trailer.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For example,
speed, altitude, road grades, outside temperature and
how much your vehicle is used to pull a trailer are all
important. And, it can also depend on any special
equipment that you have on your vehicle.
4-33

Trailer Wiring Harness
If you have the optional trailering package, your vehicle
will have an eight-wire harness, including the center
high-mounted stoplamp battery feed wire. The harness
is stored on the passenger’s side of the vehicle near
the rear wheel well. This harness has a
30 amp battery
feed wire and no connector, and should be wired by
a qualified electrical technician. After choosing an
aftermarket trailer mating connector pair, have the
technician attach one connector to the eight-wire trailer
harness and the other connector to the wiring harness
on the trailer. Be sure the wiring harness on the trailer
is
taped or strapped to the trailer’s frame rail and leave
it loose enough
so the wiring doesn’t bend or break, but
not
so loose that it drags on the ground. The eight-wire
harness must be routed out of your vehicle between
the rear door and the floor, with enough of the harness
left on both sides
so that the trailer or the body won’t
pull it. If you do not have the optional trailering
package, your vehicle will still have a trailering harness.
The harness is located near the passenger’s side
rear wheel well. It consists
of six wires that may be
used by after-market trailer hitch installers. The
technician can use the following color code chart
when connecting the wiring harness to your trailer.
e
e
Brown: Rear lamps.
Yellow: Left stoplamp and turn signal.
Dark Green: Right stoplamp and turn signal.
White (Heavy Gage): Ground.
Light Green: Back-up lamps.
White (Light Gage): Center High-Mounted Stoplamp.
Blue: Auxiliary circuit (eight-wire harness only).
Orange: Fused auxiliary (eight-wire harness only).
Store the harness in its original place. Wrap the
harness together and tie it neatly
so it won’t
be damaged.
4-4 1

When you put the fuel cap back on, turn it to the
right (clockwise) until you hear a clicking sound.
Make sure you fully install
the cap. The diagnostic
system can determine
if the fuel cap has been left off or
improperly installed. This would allow fuel to evaporate
into the atmosphere. See
Malfunction lndicator Lamp
on page 3-30.
Notice: If you need a new fuel cap, be sure to get
the right type. Your dealer can get one for you.
If you get the wrong type, it may not fit properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. See “Malfunction lndicator Lamp”
in the
Index.
Filhg a Portable Fuel Container
~
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor. You can be badly burned and your vehicle
damaged if this occurs.
To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
Do not fill a container while it is inside a
vehicle,
in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
Bring the fill nozzle in contact with the
inside of the
fill opening before operating
the nozzle. Contact should be maintained until the filling is complete.
Don’t smoke while pumping gasoline.
5-1 0

Engine Coolant
The cooling system in your vehicle is filled with
DEX-COOL@ engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240
000 km), whichever occurs first, if you add
only DEX-COOL@ extended life coolant.
The following explains your cooling system and how to
add coolant when it
is low. If you have a problem
with engine overheating, see
Engine Overheating on
page
5-3 I.
A 50/50 mixture of clean, drinkable water and
DEX-COOL@ coolant will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice: When adding coolant, it is important that
you use only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL@
is added to the
system, premature engine, heater core or radiator
corrosion may result.
In addition, the engine coolant
will require change sooner
- at 30,000 miles
(50,000 km) or 24 months, whichever occurs first. Damage
caused by the use
of coolant other than
DEX-COOL@
is not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL@ coolant which won’t damage
aluminum parts.
If you use this coolant mixture,
you don’t need to add anything else.
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture.
With plain water or the
wrong mixture, your engine could get too hot but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others could be burned. Use a
50/50 mixture of clean,
drinkable water and the proper coolant.
5-28

Brake Wear
Your vehicle has four-wheel disc brakes,
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake
pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal firmly).
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When
you hear the brake wear
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheei nuts are necessary to heip
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to
GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-31.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
5-45

1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
Notice: If the other system isn’t a 12-volt system
with a negative ground, both vehicles can be
damaged.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection you don’t want. You wouldn’t 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 firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in PARK (P) and a manual
transmission in NEUTRAL.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter
or accessory power outlets. Turn off all lamps
that aren’t needed as well as radios. This will avoid
sparks and help save both batteries. In addition,
it could save your radio!
Nofice: If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find the
positive
(+) and negative (-) terminals on each
battery.
Using a match near a battery can cause battery
gas to explode. People have been hurt doing
this, and some have been blinded. Use a
flashlight if you need more light.
Be sure the battery has enough water.
You don’t need to add water to the ACDelco@
battery installed in your new vehicle. But if
a battery has filler caps, be sure the right amount
of fluid is there. If it is low, add water
to take care
of that first. If you don’t, explosive
gas could be present.
Battery fluid contains acid that can burn you.
Don’t get
it on you. If you accidentally get it in
your eyes or on your skin, flush the place with
water and get medical help immediately.
5-48

Mix---J tires could cause yo-. JO lose control
while driving.
If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you could have a crash. Using tires of different
sizes may also cause damage to your vehicle. Be sure to use the same size and type tires on
all wheels. It’s all right to drive with your
compact spare temporarily,
it was developed
for use on your vehicle. See “Compact Spare
Tire” in the index.
If you use bias-ply tires on yo^. vet,,Je, the
wheel rim flanges 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 your vehicle.
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, 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
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.
5-67

GM Vehicle Care/Appearance Materials (cont’d)
I DescriDtion I Usage
Chrome and Wire
Wheel Cleaner Removes
dirt and grime
from chrome wheels and
wire wheel covers.
I
I Removes dust, I
Finish Enhancer fingerprints,
and surface
contaminants, Spray on
wipe
off.
I I Removes swirl marks, I
I Swirl Remover Polish fine scratches and
other light surface
I I contamination.
Removes light scratches
and protects finish.
Foaming Tire Shine
Low Gloss Cleans, shines
and
protects in one easy step,
no wiDinq necessary.
GM Vehicle Care/Appearance Materials
(cont’d)
I Description I Usage
Wash Wax Concentrate Medium foaming
shampoo. Cleans and lightly waxes.
Biodegradable and
DhosDhate free.
Spot Lifter Quickly and easily
removes spots and stains
from carpets, vinyl and
cloth upholstery.
Odor Eliminator Odorless
spray odor
eliminator used on
fabrics, vinyl, leather
and carpet.
See your General Motors parts department for these
products. See
Part D: Recommended Fluids and
Lubricants on page
6-32.
5-90

Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of fires caused by electrical problems.
Look at the silver-colored band inside the fuse.
If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical
size and rating.
Spare fuses and a fuse puller are located in the
underhood fuse block. You can remove fuses with
the fuse puller. Remember to replace any of the spare
fuses you use,
so you will have some if you ever
need them again.
If you ever have a problem on the road and don’t have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle
that you can get along without
- like the radio or
cigarette lighter
- and use its fuse, if it is the correct
amperage. Replace it as soon as you can.
There are two fuse blocks in your vehicle: one
is inside
the vehicle and one is in the engine compartment.
Instrument Panel Fuse Block
The fuse block is located on the lower portion of the
instrument panel on the driver’s side.
5-93