2004 GMC ENVOY XL check engine

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.
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 5-4. 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.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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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.
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. United States
Canada
United StatesCanada
United StatesCanada
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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.
Gate Ajar Light
If this light comes on, your liftgate or liftglass is ajar.
Try closing the liftgate or liftglass again. Never drive
with the liftgate or liftglass even partially open.
United States
Canada
United StatesCanada
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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 to 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 Curb View Assist
Mirrors” 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 3-43for more information.
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Audio System(s)
Notice:Before adding any sound equipment to
your vehicle, like a tape player, CB radio, mobile
telephone, or two-way radio, make sure that it can
be added by checking with your dealer. Also,
check federal rules covering mobile radio and
telephone units. If sound equipment can be added,
it is very important to do it properly. Added
sound equipment may interfere with the operation
of your vehicle’s engine, 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.
Figure out which audio system is in your vehicle, nd
out what your audio system can do, and how to operate
all of its controls.
Your vehicle has a feature called Retained Accessory
Power (RAP). With RAP, the audio system can be
played even after the ignition is turned off. See
“Retained Accessory Power (RAP)” underIgnition
Positions on page 2-20.
Setting the Time
The radio may have a button marked with an H or HR to
represent hours and an M or MN to represent minutes.
Press and hold the hour button until the correct hour
appears on the display. AM or PM will appear on
the display for morning or evening hours. Press and
hold the minute button until the correct minute appears
on the display. The time can be set with the ignition
on or off.
To synchronize the time with an FM station broadcasting
Radio Data System (RDS) information, press and
hold the hour and minute buttons at the same time for
two seconds until UPDATED and the clock symbol
appear on the display. If the time is not available from
the station, NO UPDAT will appear on the display.
RDS time is broadcast once a minute. After tuning to an
RDS broadcast station, it may take a few minutes for
the time to update.
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