2004 GMC ENVOY check engine

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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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.Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-4. 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.
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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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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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Fuel Information
Use the fuel information button to scroll through the
range, average fuel economy, instant fuel economy and
the GM Oil Life System.
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 monitor after an oil
change. To reset the monitor, press and hold the select
button while ENGINE OIL LIFE is displayed.
The oil change monitor does not measure how much oil
you have in your engine. So, be sure to check your
oil level often. For more information, seeEngine Oil on
page 5-16.
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ENGINE COOLANT HOT/ENGINE
OVERHEATED
If the cooling system temperature gets hot, this message
will appear in the DIC and you will hear a chime.
Refer to “Engine Overheating” for the proper course of
action. This message will clear when the coolant
temperature drops 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. Press the select
button to acknowledge this message and clear it
from the DIC display.
SERVICE AIR BAG
If there is a problem with the air bag system this
message will be displayed on the DIC. Have a qualied
technician inspect the system for problems. Press
the select button to acknowledge this message and clear
it from the DIC display.
SERVICE BRAKE SYSTEM
If a problem occurs with the brake system this message
will appear on the DIC. If this message appears, stop
as soon as possible and turn off the vehicle. Restart the
vehicle and check for the message on the DIC display.
If the message is still displayed, or appears again when
you begin driving, the brake system needs service.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will
hear a chime. Move the turn signal/multifunction lever to
the off position. Press the select button to acknowledge
this message and clear it from the DIC display.
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LEFT REAR DOOR AJAR
If the driver’s side rear 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. Press the
select button tol acknowledge this message and clear it
from the DIC display.
RIGHT REAR DOOR AJAR
If the passenger’s side rear 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. Press the
select button to acknowledge this message and clear
it from the DIC display.
RFA # BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. Press the select button
to acknowledge this message and clear it from the
DIC display.
CURB VIEW ACTIVATED
The CURB VIEW ACTIVATED message is displayed
when one of the outside rear view mirrors move into the
curb view position. Refer to “Outside Automatic
Dimming Mirror with Curb View Assist” for more
information.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear on the DIC and a chime will
sound. Fully reinstall the fuel cap. 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. The
DIC message will remain on until the message is
cancelled with the return button on the steering wheel.
The DIC message will also be cancelled if the ignition
is turned off.
The DIC message and the Service Engine Soon light
may come on again during a second trip if the fuel cap is
still not tightened properly. SeeMalfunction Indicator
Lamp on page 3-40for more information.
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