2002 GMC ENVOY check engine

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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.
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.

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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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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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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.
The DIC does not replace the need to maintain your
vehicle as recommended in the Maintenance Schedule
in this manual. Also, the oil change reminder will not
detect dusty conditions or engine malfunctions that may
affect the oil. Also, the oil change reminder does not
measure how much oil you have in your engine. So, be
sure to check your oil level often. See ªEngine Oilº in
the Index.Personalization Button
You can program certain features to a preferred setting
for up to two people. Press the personalization button
to scroll through the following personalization features.
All of the personalization options may not be available
on your vehicle. Only the options available will be
displayed on your DIC.

ALARM WARNING TYPE

AUTOMATIC LOCKING

AUTOMATIC UNLOCKING

SEAT POSITION RECALL (If Equipped)

PERIMETER LIGHTING

REMOTE LOCK FEEDBACK

REMOTE UNLOCK FEEDBACK

HEADLAMPS ON AT EXIT

TILT MIRROR IN REVERSE (If Equipped)

EASY EXIT SEAT (If Equipped)

DISPLAY UNITS (E/M)

DISPLAY LANGUAGE
The driver's preferences are recalled by pressing the
unlock button on the remote keyless entry transmitter
or by pressing the appropriate memory button 1 or 2
located on the driver's door.

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DIC Warnings and Messages
Warning messages are displayed on the DIC to notify
the driver that the status of the vehicle has changed and
that some action may be needed by the driver to correct
the condition. More than one message may appear at
one time, they will appear one behind the other. Some
messages may not require immediate action but you
should press the select button to acknowledge that you
received the message and clear it from the display.
Some messages cannot be cleared from the display
because they are more urgent. These message required
action before they can be removed from the DIC display.
The following are the possible messages that can be
displayed and some information about them.
ENGINE COOLANT HOT/IDLE ENGINE
If the cooling system temperature gets hot this message
will appear in the DIC and you will hear a chime. Stop
the vehicle and let the engine idle in PARK (P) to allow
the coolant to reach a safe temperature. This message
will clear when the coolant temperature drops to a safe
operating temperature.ENGINE OVERHEATED/STOP ENGINE
(If Equipped)
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear
in the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine has
cooled to a safe operating temperature.
OIL PRESSURE LOW/STOP ENGINE
If low oil pressure levels occur this message will be
displayed on the DIC. Stop the vehicle as soon as safely
possible and do not operate it until the cause of the low
oil pressure has been corrected. Check your oil as soon
as possible and have your vehicle serviced.
BATTERY NOT CHARGING
If the battery is not charging during operation this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the select
button will acknowledge this message and clear it from
the DIC display.

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CHECK OIL LEVEL
If the oil level in the vehicle is low this message will
appear on the DIC. Check the oil level and correct it as
necessary. You may need to need to let the vehicle cool
or warm up and cycle the ignition to be sure this
message will clear. Once the problem is corrected,
pressing the select button will clear this message from
the DIC display.
CHECK WASHER FLUID
If the washer fluid level is low this message will appear
on the DIC. Adding washer fluid will clear the message.
Pressing the select button will acknowledge this
message and clear it from the DIC display.
TRANS HOT IDLE ENGINE
If the transmission fluid in the vehicle gets hot this
message will appear on the DIC. Driving with the
transmission fluid temperature high can cause damage to
the vehicle. Stop the vehicle and let it idle to allow the
transmission to cool. This message will clear when the
fluid temperature reaches a safe level.ICE POSSIBLE
If the outside temperature reaches a level where ice
could form on the roadway, this message may appear
on the DIC. If the temperature rises to a safe level the
message will clear. Pressing the select button will
acknowledge this message and clear it from the
DIC display.
DRIVER DOOR AJAR
If the driver's door is not fully closed this message will
appear on the display and you will hear a chime. Stop
and turn off the vehicle, check the door for obstacles,
and close the door again. Check to see if the message
still appears on the DIC. Pressing the select button
will acknowledge this message and clear it from the
DIC display.

3-60 Tips About Your Audio System
Hearing damage from loud noise is almost undetectable
until it is too late. Your hearing can adapt to higher
volumes of sound. Sound that seems normal can be
loud and harmful to your hearing. Take precautions
by adjusting the volume control on your radio to a
safe sound level before your hearing adapts to it.
To help avoid hearing loss or damage do the following:
1. Adjust the volume control to the lowest setting.
2. Increase volume slowly until you hear comfortably
and clearly.NOTICE:
Before you add any sound equipment to your
vehicle
-- like a tape player, CB radio, mobile
telephone or two
-way radio -- be sure you
can add what you want. If you can, it's very
important to do it properly. Added sound
equipment may interfere with the operation
of your vehicle's engine, Delphi Electronics
radio or other systems, and even damage them.
Your vehicle's systems may interfere with the
operation of sound equipment that has been
added improperly.
So, before adding sound equipment, check with
your dealer and be sure to check federal rules
covering mobile radio and telephone units.