2003 GMC ENVOY 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 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:Modi®cations 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.
Modi®cations 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 doesn't come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
·Light On SteadyÐ 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 ªIf
the Light Is On Steadyº 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 ªIf
the Light Is On Steadyº 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. See
Filling 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, mis®ring, 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:
Don't 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: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. 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. United States
CanadaUnited StatesCanada
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Service Four-Wheel Drive
Warning Light
This light should come on brie¯y 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 brie¯y 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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C.Personalization:Press this button to change
personal settings for some of the options on your
vehicle.
D.Select:Press this button to reset certain functions
and turn off or acknowledge 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
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).
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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
messages require 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.
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.
SERVICE AIR BAG
If there is a problem with the air bag system this
message will be displayed on the DIC. Have a quali®ed
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the DIC display.
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