2004 CHEVROLET EXPRESS CARGO VAN service

You can only drive for a short time with the reading 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
With the ignition 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 4-32. United States
Canada
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{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.
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.
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Stabilitrak®Not Ready Light
If your vehicle has the
Stabilitrak®system, this
light will come on according
to the description table for
the Stabilitrak
®system. For
more information, see
Stabilitrak
®System on
page 4-9.
You will hear three chimes if the light turns on and one
chime if the light turns off.
Stabilitrak®Indicator Light
If you have the Stabilitrak®
system, this light will be on
or ashing, according to the
description table for the
Stabilitrak
®system. For
more information, see
Stabilitrak
®System on
page 4-9.
You will hear three chimes if the light turns on and one
chime if the light turns off.
If this light remains on steady, your vehicle needs to be
taken in for service.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into 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
operating conditions, you should pull off the road, stop
your vehicle, and turn off the engine as soon as possible.
SeeEngine Overheating on page 5-26.
Malfunction Indicator Lamp
Check Engine Light
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 Check Engine light comes on 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. United States
Canada
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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.
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.
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A reading in the low pressure zone may be caused by a
dangerously low oil level or other problem causing
low oil pressure. Check your oil as soon as possible.
{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.
Change Engine Oil Light
This light is displayed
when the engine oil needs
to be changed.
If your vehicle has a V8 engine and this light is ashing,
it indicates that the oil level is low.
When this light is on steady, it indicates the oil needs to
be changed soon.
Once the engine oil has been changed, the change
engine oil light must be reset. Until it is reset, the light
will be displayed when the engine is on. For more
information on resetting the system, seeEngine Oil on
page 5-13.
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Reduced Engine Power Light
If the check engine and
reduced engine power
lights are on, the throttle
may be disabled and
a noticeable reduction in
the vehicle’s performance
may occur.
If the reduced engine power light is on, but there is no
reduction in performance, proceed to your destination.
The performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at a
reduced speed while the reduced engine power light is
on, but acceleration and speed may be reduced.
Anytime the check engine light stays on, the vehicle
should be taken to an authorized GM dealer as soon as
possible for service.
Daytime Running Lamps Indicator
Light
You have this light on the
instrument panel. It will
light whenever the DRL are
on. It is also a reminder
to turn on your headlamps
when driving at night.
Tow/Haul Mode Light
This message is displayed
when the tow/haul mode
has been activated.
For more information, see “Tow/Haul Mode” inTowing a
Trailer on page 4-38.
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To adjust both tone controls and both speaker controls
to the middle position, rst end out of audio mode
by pressing another button, causing the radio to perform
that function, or by waiting ve seconds for the display
to return to time of day. Then press and hold AUDIO for
more than two seconds until you hear a beep. CEN
will appear on the display.
Adjusting the Speakers (Balance/Fade)
AUDIO:To adjust the balance between the right
and the left speakers, press and release the AUDIO
button until BAL appears on the display. Then press and
hold the up or the down arrow to move the sound
toward the right or the left speakers.
To adjust the fade between the front and the rear
speakers, press and release AUDIO until FAD appears
on the display. Then press and hold the up or the
down arrow to move the sound toward the front or the
rear speakers.
To adjust balance or fade to the middle position, select
BAL or FAD. Then press and hold AUDIO for more
than two seconds until you hear a beep. L and a zero
or F and a zero will appear on the display.To adjust both tone controls and both speaker controls
to the middle position, rst end out of audio mode
by pressing another button, causing the radio to perform
that function, or by waiting ve seconds for the display
to return to time of day. Then press and hold AUDIO for
more than two seconds until you hear a beep. CEN
will appear on the display.
Radio Messages
CAL (Calibration):The audio system has been
calibrated for your vehicle from the factory. If CAL
appears on the display it means that the radio has not
been congured properly for your vehicle and must
be returned to the dealer for service.
LOC (Locked):This message is displayed when the
THEFTLOCK
®system has locked up. Take the vehicle
to the dealer for service.
If any error occurs repeatedly or if an error cannot be
corrected, contact your dealer.
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