2004 CHEVROLET TRAIL BLAZER service

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 to indicate that there is aproblem 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 possibleIf 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 5-5. 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, 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.
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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).
{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.
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. United States
Canada
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Change Engine Oil Light
When this light comes on, it means that service is
required for your vehicle. SeeScheduled Maintenance
on page 6-4andEngine Oil on page 5-15for more
information.
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.
Security Light
This light will come on briey when you turn the key
toward 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 dealer.
Also, seeContent Theft-Deterrent on page 2-16for
additional information regarding the SECURITY light. United States
CanadaUnited StatesCanada
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Cruise Control Light
Your vehicle may have this feature. The CRUISE light
appears whenever you set your cruise control.
Reduced Engine Power Light
This light is displayed when a noticeable reduction in
the vehicle’s performance may occur. The vehicle may
be driven at a reduced speed when the reduced
engine power light is on but acceleration and speed
may be reduced. The performance may be reduced until
the next time you drive your vehicle. If this light stays
on, see your dealer as soon as possible for diagnosis
and repair.
This light may also come on if there is a problem with
the Electronic Throttle Control (ETC) system. If this
happens, take the vehicle in for service as soon
as possible. United States
CanadaUnited StatesCanada
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Service Four-Wheel Drive
Warning Light
This light should come on briey when you turn on the
ignition, as a check to show you it is working.
The SERVICE 4WD 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.
Check Gages Warning Light
The CHECK GAGES light will come on briey 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. United StatesCanada
United StatesCanada
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DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver and 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 the trip stem will acknowledge
any warning or service messages. Pressing any of
the DIC steering wheel buttons (Trip Information, Fuel
Information, Personalization or Select button) will
also acknowledge any warnings or service messages.
The DIC has different modes which can be accessed by
pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization and
select. The button functions are detailed following.
Trip Information
Use the trip information button to scroll through the
odometer, TRIP A, TRIP B and TIMER.
Odometer
Press the trip information button until the odometer
appears on the display. This shows the total distance
the vehicle has been driven in either miles or kilometers.
Pressing the reset stem located on the instrument
cluster with the vehicle off will also display the odometer.
Trip A and Trip B
Press the trip information button until TRIP A or TRIP B
is displayed. This shows the current distance traveled
since the last reset for each trip odometer in either miles
or kilometers. Both odometers can be used at the
same time.
Each trip odometer can be reset to zero separately by
pressing select while the desired trip odometer is
displayed. You can also reset the trip odometers with
the reset stem on the cluster. If you press and hold the
reset stem for four seconds, the display will show the
distance traveled since the last ignition cycle.
Timer
The DIC can be used as a stopwatch. Press the select
button while TIMER is displayed to start the timer.
The display will show the amount of time that has
passed since the timer was last reset (not including time
the ignition is off). Time will continue to be counted as
long as the ignition is on, even if another display is being
shown on the DIC. The timer will record up to 99 hours,
59 minutes and 59 seconds (99:59:59) after which
the display will roll back to zero.
To stop the counting of time, press the select button
briey while TIMER is displayed.
To reset the timer to zero, press and hold the select
button while TIMER is displayed.
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