2003 CHEVROLET ASTRO engine

Warning Lights, Gages and
Indicators
This part describes the warning lights and gages that
may be on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or
is a
problem with one of your vehicle’s functions.
As you
will see in the details on the next few pages, some
warning lights come on briefly when you start the engine
just to let you know they’re working.
If you are familiar
with this section, you should not be alarmed when
this happens. Gages
can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one
of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly
- and even
dangerous.
So please get to know your warning lights
and gages. They’re a big help.
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If the air bag readiness light stays on after you start the
vehicle or comes on when
you are driving, your air
bag system may not work properly. Have your vehicle
s iced right away.
Charging System
If the air bag readiness light stays on after you
start your vehicle,
it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate
in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to
RUN.
If the light doesn’t come on then, have it fixed so
it will be ready to warn you if there is a problem.
Light
This light should come on
briefly when you turn on
the ignition, before starting the engine, as a check
to show you it is working.
After the engine starts, the light should go out.
if it stays
on or comes on while you are driving, you may have
a problem with your charging system. It could indicate a
problem with the generator drive belt, or some other
charging system problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with this light
on,
it helps to turn off all your accessories, such as
the radio and air conditioner.
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Voltmeter Gage
When your engine is not
running, but the ignition is
on (in the RUN position),
the gage shows your
battery’s state of charge
in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between
the low and high warning zones indicate the normal
operating range.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition
is normal since the
charging system
is not able to provide full power at engine
idle.
As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
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.
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BRAKE
This light should come on
briefly when you turn
the ignition key to
RUN.
If it doesn’t come on then,
have it fixed
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
floor. It may take longer to stop. If the light is still
on, have the vehicle towed for service. See
Towing
Your Vehicle on page 4-29.
I
You- -)rake 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’ve pulled off the road and stopped
carefully, have the vehicle towed for service.
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 briefly when you turn the ignition key to
RUN.
If the light doesn’t come on then, have it fixed so
it will be ready to warn you if there is a problem.
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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.
See
Engine Overheating on page 5-31.
Malfunction Indicator Lamp
Service Engine Soon Light in the
United States
or Check Engine Light
in Canada
SERVICE
ENGINE
SOON
ds
CHECK
United States Canada
Your vehicle is equipped with a computer which
monitors operation of the fuel, ignition and emission
control systems.
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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: Modifications 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. Modifications 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.
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 doesn’t come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:
e
e Light Flashing - A misfire condition has been
detected.
A misfire increases vehicle emissions
and may damage the emission control system on
your vehicle. Dealer or qualified service center
diagnosis and service may be required.
Light On Steady
- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis
and service may be required.
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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 flashing and remains on steady,
see
“If the Light Is On Steady” following.
If the light continues to flash, 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 flashing,
follow the previous steps, and drive the vehicle to
your dealer or qualified service center for service.
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. See
Filling Your Tank on page 5-8.
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.
Have you recently changed brands of fuel?
If
so, be sure to fuel your vehicle with quality fuel.
See
Gasoline Octane on page 5-5. 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, misfiring,
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.
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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,
have your dealer or qualified service center check
the vehicle. Your dealer has the proper test equipment
and diagnostic tools to fix 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, see your dealer or qualified
service center to prepare the vehicle for inspection.
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