2008 GMC ENVOY Owner's Manual

If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 the Tank on page 5-8. The diagnostic
system can determine if the fuel cap has been left off orimproperly installed. A loose or missing fuel cap allows
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 vehicle’s electrical system might be wet.
The condition is usually 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 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might 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 might 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/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might 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 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 the battery or if the battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This can 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
dealer/retailer can prepare the vehicle for inspection.
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).United States
Canada
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{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.
Change Engine Oil Light
Your vehicle may have a
change engine oil light.
When this light comes on it means that an oil change
and other maintenance procedures are required for your
vehicle.
SeeScheduled Maintenance on page 6-4andEngine
Oil on page 5-16for more information.
Once the engine oil has been changed, the change
engine oil light must be reset. Until it is reset, the light
will stay on when the engine is on.
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Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-16.
Cruise Control Light
If your vehicle has a Driver
Information Center (DIC),
this light will come on when
the cruise control is set.
SeeCruise Control on page 3-11andDIC Warnings
and Messages on page 3-53for more information.
Reduced Engine Power Light
This light comes on when
a noticeable reduction in
the vehicle’s performance
occurs.
The vehicle can 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.
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Highbeam On Light
This light comes on when
the high-beam headlamps
are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8
for more information.
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 four-wheel drive 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 dealer
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.
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Gate Ajar Light
If this light comes on, the
liftgate or liftglass is not
completely shut.
Close the liftgate or liftglass. 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.
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.
United StatesCanada
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Low Fuel Warning Light
The light next to the fuel gage will come on briey 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. SeeFuel on
page 5-5.
Check Gas Cap Light
If your vehicle has this
light, it will come on if your
gas cap is not securely
fastened.
SeeMalfunction Indicator Lamp on page 3-41for more
information.
Driver Information Center (DIC)
Your vehicle may have this feature. The Driver
Information Center (DIC) display is located on the
instrument panel cluster, below the speedometer.
If your vehicle has DIC buttons, they are located on
the steering wheel. The DIC can display information
such as the trip odometer, fuel economy, customization
features, and warning/status messages.
If your vehicle does not have DIC steering wheel
buttons, you will not have all of the features listed.
Scroll through the odometer and trip odometer by
pressing the trip odometer reset stem located on the
instrument panel cluster. Turn off, or acknowledge, DIC
messages by pressing the trip odometer reset stem.
SeeSpeedometer and Odometer on page 3-32for
information on features for vehicles without DIC buttons.
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3(Trip Information):Press this button to display
the odometer, trip odometers, tire pressure, and timer.
t(Fuel Information):Press this button to display
the current range, fuel used, average fuel economy,
and engine oil life.
4(Customization):Press this button to access the
vehicle settings menu and customize the personal
settings on your vehicle.
r(Select):Press this button to reset certain DIC
functions and set your customization settings.
Pressing any of the DIC buttons will acknowledge DIC
messages and clear them from the DIC display.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display 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 trip stem will acknowledge
any warning or service messages. Pressing any of
the DIC steering wheel buttons — trip information, fuel
information, customization, or select button — will
also acknowledge any warnings or service messages.
You should take any message that appears on the
display seriously and remember that clearing the
message will only make the message disappear,
not correct the problem.
The DIC has different modes which can be accessed by
pressing the four DIC buttons located on the steering
wheel. These buttons are trip information, fuel
information, customization, and select. The button
functions are detailed in the following pages.
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