2004 CHEVROLET ASTRO check engine light

Security Light
This light will come on
brie¯y when you turn the
ignition key to START.
The light will stay on until the engine starts. If the light
¯ashes, the Passlock
žSystem has entered a tamper
mode. If the vehicle fails to start, seePasslockž
on page 2-16.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
ž
System. Your vehicle will not be protected by Passlockž,
and you should see your GM dealer.
Service All-Wheel Drive Light
This light should come on
brie¯y when you turn on
the ignition, as a check to
show you it is working.
The SERVICE AWD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
3-35

Tow/Haul Mode Light
This light should come on
when the tow/haul mode
has been selected.
For more information, see ªTow/Haul Modeº in
Towing a
Trailer on page 4-35.
Check Gages Warning Light
The CHECK GAGES light
will come on brie¯y when
you are starting the
engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil
pressure gages to see if they are in the warning zones.
Fuel Gage
The fuel gage tells you approximately how much fuel
you have remaining when the ignition is on.
When the gage ®rst indicates empty, you still have a
little fuel left, but you should get more fuel as soon
as possible.
United StatesCanada
3-36

Avoid needless heavy braking. Some people drive
in spurts Ð heavy acceleration followed by heavy
braking Ð rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with the anti-lock brake system,
this warning light will stay on. See
Anti-Lock Brake
System Warning Light on page 3-27. United States
Canada
4-7

{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You can not see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
4-27

Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission ¯uid (don't over®ll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you ®nd them quickly. If
you're trailering, it's a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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 quali®ed 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-wireharness must be routed out of your vehicle between the
rear door and the ¯oor, 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.
·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.
4-44

How to Inspect the Engine Air
Cleaner/Filter
To inspect the engine air cleaner/®lter remove the ®lter
from the vehicle and lightly shake ®lter to release
loose dust and dirt. If the ®lter remains caked with dirt, a
new ®lter is required.
To inspect or replace the ®lter, do the following:
1. Unsnap both clips on the cover.
2. Remove the cover.
3. Change the ®lter.
4. Snap both clips to secure the engine air
cleaner/®lter cover.
{CAUTION:
Operating the engine with the air cleaner/®lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stop ¯ame if the engine back®res. If it is not
there and the engine back®res, you could
be burned. Do not drive with it off, and be
careful working on the engine with the air
cleaner/®lter off.
Notice:If the air cleaner/®lter is off, a back®re can
cause a damaging engine ®re. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/®lter in place when you
are driving.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter every 15,000 miles
(25,000 km) if the vehicle is mainly driven under one or
more of these conditions:
·In heavy city traffic where the outside temperature
regularly reaches 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter every 50,000 miles
(83 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
5-22

How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission ¯uid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-30.
Using a funnel, add ¯uid down the transmission dipstick
tube only after checking the transmission ¯uid while it
is hot. (A cold check is used only as a reference.) If the
¯uid level is low, add only enough of the proper ¯uid
to bring the level up to the HOT area for a hot check. It
doesn't take much ¯uid, generally less than one pint
(0.5 L).
Don't over®ll.
Notice:We recommend you use only ¯uid labeled
DEXRONž-III, because ¯uid with that label is
made especially for your automatic transmission.
Damage caused by ¯uid other than DEXRON
ž-III is
not covered by your new vehicle warranty.
·After adding ¯uid, recheck the ¯uid level as
described under²How to Check.²
·When the correct ¯uid level is obtained, push the
dipstick back in all the way; then ¯ip the handle
down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add
only DEX-COOL
žextended 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 5-28.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOLžmay
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs ®rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
ž(silicate-free) coolant in your vehicle.
5-25

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.
4. Open the hoods and locate the batteries. Find
the positive (+) and negative (-) terminals on
each battery.
{CAUTION:
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
¯ashlight if you need more light.
Be sure the battery has enough water. You do
not need to add water to the ACDelco
žbattery
installed in your new vehicle. But if a battery
has ®ller caps, be sure the right amount of
¯uid is there. If it is low, add water to take care
of that ®rst. If you do not, explosive gas could
be present.
Battery ¯uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ¯ush the place
with water and get medical help immediately.
{CAUTION:
Fans or other moving engine parts can injure
you badly. Keep your hands away from moving
parts once the engine is running.
5. Check that the jumper cables don't have loose or
missing insulation. If they do, you could get a
shock. The vehicles could be damaged too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will go to
positive (+) or to a remote positive (+) terminal if
the vehicle has one. Negative (-) will go to a heavy,
unpainted metal engine part, or to a negative (-)
terminal if the vehicle has one.
Don't connect positive (+) to negative (-) or you'll
get a short that would damage the battery and
maybe other parts, too. And don't connect
the negative (-) cable to the negative (-) terminal
on the dead battery because this can cause sparks.
5-44