2004 CHEVROLET COLORADO service

Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the air bag sensors, the air
bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
systems, seeAir Bag Systems on page 1-62.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. Then
the light should go out.
This means the system
is ready.
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
serviced right away.{CAUTION:
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 inate in a crash, or they
could even inate 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 ash for a few
seconds 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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{CAUTION:
If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger’s frontal air
bag could inate even though the switch is off.
If this ever happens, do not let anyone whom
the national government has identied as a
member of a passenger air bag risk group sit
in the right front passenger’s position (for
example, do not secure a rear-facing child
restraint in the right front passenger’s seat)
until you have your vehicle serviced.
Battery Warning Light
This light will come on
briey when you start the
vehicle, as a check to
show you it is working;
then it should go out.
If it stays on, or comes on while you are driving, you
may have a problem with the electrical charging system.
Have it checked right away. Driving while this light is
on could drain your battery and result in a vehicle that
may stall.
If you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and climate control system.
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Up-Shift Light (Manual
Transmission)
This light appears when
you need to shift to the
next higher gear on
a manual transmission
vehicle.
Shifting when the indicator light is on will help you get
the best fuel economy. See “Up-Shift Light” under
Manual Transmission Operation on page 2-25for
more information.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into two
parts. If one part is not 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 ON. If it does not come on then, have
it xed so it will be ready to warn you if there is
a problem.
When the ignition is on, the brake system warning light
will also come on when you set your parking brake.
SeeParking Brake on page 2-31for more information.
The light will stay on if your parking brake does not
release fully. If it stays on after your parking brake is
fully released, it means you have a brake 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 4-44.
United StatesCanada
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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 briey when you
start your engine to show it
is working. Then it will
turn off. This is 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. SeeBrake System Warning Light on page 3-22.
The anti-lock brake system warning light should come
on briey when you turn the ignition key to ON. 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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Engine Coolant Temperature Gage
This gage shows
the engine
coolant temperature.
If the gage pointer is near the top of the gage, the
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 5-28for
more information.
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.
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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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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.
Oil Pressure Light
{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.This light tells you if there
could be a problem with
your engine oil pressure.
The light goes on when you turn your key to ON or
START. It goes off once you start your engine. That’s a
check to be sure the light works. If it doesn’t come
on, be sure to have it xed so it will be there to warn
you if something goes wrong.
When the light comes on and stays on, it means that oil
isn’t owing through your engine properly. You could
be low on oil and you might have some other system
problem. SeeEngine Oil on page 5-13and “OIL” under
DIC Warnings and Messages on page 3-32for
more information.
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Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster. The DIC can display information such as the trip
odometer, and personalization features.
DIC Controls and Displays
The Driver Information Center (DIC) comes on when the
ignition is on. After a short delay the DIC will display
the information that was last displayed before the engine
was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing and releasing the trip odometer
reset stem on the DIC will acknowledge some current
warnings or service messages. Some message will only
clear once the required action has been taken.
The DIC has different modes which can be accessed by
pressing the trip odometer reset stem on the DIC.
These modes are explained following. The DIC trip
odometer reset stem is located on the instrument panel
cluster next to the DIC display. To scroll through the
available functions, press and release the reset stem.
Trip Information
Odometer
The odometer is automatically displayed on the DIC
when you start the vehicle. The odometer shows
the total distance the vehicle has been driven in either
miles or kilometers.
Trip Odometer
Press and release the reset stem until TRIP appears on
the DIC display. This shows the current distance
traveled since the last reset of the trip odometer in either
miles or kilometers.
Press and hold the reset stem for approximately four
seconds to reset the trip odometer.
GM Oil Life System™
Press the reset stem until OIL LIFE appears (ashing)
on the display. The GM Oil Life System™ shows
an estimate of the oil’s remaining useful life. It will show
OIL LIFE on the display when the system is reset
after an oil change. It will alert you to change your oil on
a schedule consistent with your driving conditions.
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