2004 CHEVROLET ASTRO CARGO VAN service

You can only drive for a short time with the readings
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Brake System Warning Light
When the ignition is on, the brake system warning light
will come on when you set your parking brake. The
light will stay on if your parking brake doesn’t release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
Your vehicle’s hydraulic brake system is divided into two
parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.This light should come on
briey when you turn the
ignition key to RUN. If
it doesn’t come on then,
have it xed so it will
be ready to warn you if
there’s a problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal
is harder to push. Or, the pedal may go closer to
the oor. It may take longer to stop. If the light is still
on, have the vehicle towed for service. SeeTowing Your
Vehicle on page 4-29.
{CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you
have pulled off the road and stopped carefully,
have the vehicle towed for service.
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Anti-Lock Brake System
Warning Light
With the anti-lock brake system, this light will come
on when you start your engine and may stay on
for several seconds. That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the regular brake system
warning light isn’t on, you still have brakes, but you don’t
have anti-lock brakes. If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there’s a problem with your regular brakes. See
“Brake System Warning Light” earlier in this section.
The anti-lock brake system warning light should
come on briey when you turn the ignition key to RUN.
If the light doesn’t come on then, have it xed so it
will be ready to warn you if there is a problem.
Engine Coolant Temperature Gage
This gage shows
the engine coolant
temperature. If the
gage pointer moves
to the red area, your
engine is too hot!
It means that your engine coolant has overheated.
If you have been operating your vehicle under normal
driving conditions, you should pull off the road, stop your
vehicle and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-29. United States
Canada
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Malfunction Indicator Lamp
Service Engine Soon Light
in the United States or
Check Engine Light in Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition, and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The SERVICE ENGINE SOON or CHECK
ENGINE light comes on and a chime will sound to
indicate that there is a problem and service is required.Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with
this light on, after a while, your emission controls
may not work as well, your fuel economy may not be
as good, and your engine may not run as smoothly.
This could lead to costly repairs that may not be
covered by your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test. United States
Canada
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This light should come on, as a check to show you
it is working, when the ignition is on and the engine
is not running. If the light does not come on, have
it repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system
on your vehicle. Diagnosis and service may
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see “If
the Light Is On Steady” following. If the light is still
ashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x
any mechanical or electrical problems that may
have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this inspection
could prevent you from getting a vehicle registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the SERVICE
ENGINE SOON or CHECK ENGINE light is on or not
working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
3-31

Oil Pressure Gage
The oil pressure gage
shows the engine oil
pressure in psi (pounds
per square inch) when
the engine is running.
Canadian vehicles indicate pressure in kPa
(kilopascals). Oil pressure may vary with engine speed,
outside temperature and oil viscosity, but readings
above the low pressure zone indicate the normal
operating range.
A reading in the low pressure zone may be caused by
a dangerously low oil level or other problems causing
low oil pressure.{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance
may damage the engine. The repairs would not
be covered by your warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
3-32

Security Light
This light will come on
briey when you turn the
ignition key to START.
The light will stay on until the engine starts. If the light
ashes, the Passlock
®System has entered a tamper
mode. If the vehicle fails to start, seePasslock®
on page 2-17.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
System. Your vehicle will not be protected by Passlock®,
and you should see your GM dealer.
Service All-Wheel Drive Light
This light should come on
briey 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.
3-33

Once you are moving on the freeway, make certain
you allow a reasonable following distance. Expect
to move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit,
do not, under any circumstances, stop and back up.
Drive on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted.
Reduce your speed according to your speedometer,
not to your sense of motion. After driving for any
distance at higher speeds, you may tend to think you
are going slower than you actually are.
Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested. If you
must start when you are not fresh — such as after
a day’s work — do not plan to make too many miles
that rst part of the journey. Wear comfortable clothing
and shoes you can easily drive in.Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it needs
service, have it done before starting out. Of course, you
will nd experienced and able service experts in GM
dealerships all across North America. They will be ready
and willing to help if you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir full?
Are all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all inated
to the recommended pressure?
Weather Forecasts:What is the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
Maps:Do you have up-to-date maps?
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