2003 GMC ENVOY ignition

If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
This light should come on brie¯y when you turn the
ignition key to RUN. If it doesn't come on then, have it
®xed so it will be ready to warn you if there's a
problem.If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
¯oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. See
Towing
Your Vehicle on page 4-45.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you've pulled off the road and stopped
carefully, have the vehicle towed for service. United StatesCanada
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Anti-Lock Brake System
Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds. That's
normal. A chime may also
sound when the light
comes on.
If the light stays on, or comes on when you're driving,
your vehicle needs service. If the regular brake
system warning light isn't on, you still have brakes, but
you don't have anti-lock brakes. If the regular brake
system warning light is also on, you don't have anti-lock
brakes and there's a problem with your regular
brakes. See
Brake System Warning Light on page 3-39earlier in this section.
The anti-lock brake system warning light should come
on brie¯y when you turn the ignition key to RUN. If
the light doesn't come on then, have it ®xed so it will be
ready to warn you if there is a problem.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, it means that
your engine coolant has overheated. If you have been
operating your vehicle under normal driving conditions,
you should pull off the road, stop your vehicle and
turn off the engine as soon as possible.
See
Engine Overheating on page 5-27for more
information.
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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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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
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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.
Fuel Gage
When the ignition is on, the fuel gage tells you about
how much fuel you have remaining. United States
Canada
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3-49

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 ®ll 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
®ll 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 Warning Light
The light next to the fuel gage will come on brie¯y 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
Fuel on
page 5-4.
Driver Information Center (DIC)
Your vehicle may have this feature. 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. The DIC buttons are located
on the steering wheel.
A.Trip Information:Press this button to display the
odometer, trip odometer and the timer.
B.Fuel Information:Press this button to display the
current range, average fuel economy, instant
fuel economy and engine oil life.
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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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