engine CHEVROLET TRAIL BLAZER 2002 1.G Owner's Guide

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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 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 the SERVICE ENGINE SOON or
CHECK ENGINE 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.

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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 doesn't come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:

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.
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 ªIf
the Light Is On Steadyº 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 ªIf the Light
Is On Steadyº 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 ªFilling Your Tankº in the Index. 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.

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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
ªFuelº in the Index. 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.
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 in order 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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Oil Pressure Gage
United States Canada
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:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
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.

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Change Engine Oil Light
United States Canada
This light is displayed when the engine oil needs to
be changed.
Once the engine oil has been changed, the CHANGE
ENG 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, see ªOil Life
Systemº in the Index.
Security Light
United States Canada
This light will come on briefly when you turn the
key toward START. The light will stay on until the
engine starts.
If the light flashes, the Passlock

system has entered a
tamper mode. If the vehicle fails to start, see ªPasslockº
in the Index.
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, see ªContent Theft
-Deterrentº in the Index for
additional information regarding the SECURITY light.

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Cruise Control Light (If Equipped)
United States Canada
The CRUISE light appears whenever you set your cruise
control. See ªCruise Controlº in the Index.
Reduced Engine Power
United States Canada
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.

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Service Four-Wheel-Drive Warning Light
(If Equipped)
United States Canada
This light should come on briefly 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 Light
United States Canada
The CHECK GAGES light will come on briefly 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.

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Here are four things that some owners ask about. None
of these show a problem with your fuel gage:

At the gas station, the gas pump shuts off before the
gage reads full.

It takes a little more or less fuel to fill up than the
gage indicated. For example, the gage may have
indicated the tank was half full, but it actually took a
little more or less than half the tank's capacity to fill
the tank.

The gage moves a little when you turn a corner or
speed up.

The gage doesn't go back to empty when you turn
off the ignition.Low Fuel Light
United States Canada
The light next to the fuel gage will come on briefly
when you are starting the engine.
This light comes on when the fuel tank is low on fuel.
To turn it off, add fuel to the fuel tank. See ªFuelº in
the Index.

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Driver Information Center (DIC)
(If Equipped)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features.
A.Trip Information: This button will display the
odometer, trip odometer and the timer.
B.Fuel Information: This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.
C.Personalization: This button will change personal
options available on your vehicle.
D.Select: This button resets certain functions and turns
off or acknowledges messages on the DIC.
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 select button will
acknowledge any current warning 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 in
the following.
Trip Information Button
Use the trip information button to scroll through the
odometer, TRIP A, TRIP B and TIMER.

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Fuel Range
Press the fuel information button until RANGE appears
to display the remaining distance you can drive without
refueling. It's based on fuel economy and the fuel
remaining in the tank. The display will show LOW if
the fuel level is low.
The fuel economy data used to determine fuel range is
an average of recent driving conditions. As your driving
conditions change, this data is gradually updated. Fuel
range cannot be reset.
Average Fuel Economy
Press the fuel information button until AVG appears in
the display. Average fuel economy is how many miles
per gallon your vehicle is getting based on current and
past driving conditions.
Press and hold the select button while AVG. ECON is
displayed to reset the average fuel economy. Average
fuel economy will then be calculated starting from that
point. If the average fuel economy is not reset, it will be
continually updated each time you drive.Instant Fuel Economy
Press the fuel information button until INST appears
in the display. Instant fuel economy is how many miles
per gallon your vehicle is at the particular moment in
time. The instant fuel economy cannot be reset.
GM Oil Life System

Press the fuel information button until ENGINE OIL
LIFE appears in the display. The GM Oil Life System

shows an estimate of the oil's remaining useful life. It
will show 100% 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.
Always reset the engine oil life after an oil change.
To reset the Oil Life System press and hold the select
button while ENGINE OIL LIFE is displayed. Be
careful not to reset the engine oil life accidentally at
any time other than when the oil has just been changed.
It can't be reset accurately until the next oil change.