light GMC ENVOY 2008 Repair Manual

Malfunctions often are indicated by the system before
any problem is apparent. This can 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, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.
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 can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-3.This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system
on your vehicle. Diagnosis and service might
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
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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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CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked. If a tire
pressure message appears on the DIC, stop as soon
as you can. Have the tire pressures checked and set to
those shown on the Tire Loading Information label.
SeeTires on page 5-57,Loading Your Vehicle on
page 4-34, andInflation - Tire Pressure on page 5-64.
The DIC also shows the tire pressure values. See
DIC Operation and Displays on page 3-50. If the tire
pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-41.
CHECK WASHER FLUID
This message displays if the washer uid level is low.
Adding washer uid to the windshield washer uid
reservoir clears this message. SeeWindshield Washer
Fluid on page 5-37. This message clears itself after
10 seconds, or you can manually clear it from the
DIC display.
CURB VIEW ACTIVATED
This message displays when the passenger outside
rearview mirror moves into the curb view position.
SeeOutside Curb View Assist Mirror on page 2-47
for more information.
DRIVER DOOR AJAR
This message displays and a chime sounds if the driver
door is not fully closed. Stop and turn off the vehicle,
check the door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
ENGINE COOLANT HOT/ENGINE
OVERHEATED
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-28for more information.
This message displays and a chime sounds if the
cooling system temperature gets hot. SeeEngine
Overheating on page 5-28for the proper course of
action. This message clears when the coolant
temperature drops to a safe operating temperature.
FUEL LEVEL LOW
This message displays and a chime sounds if the fuel
level is low. Refuel as soon as possible. SeeLow
Fuel Warning Light on page 3-49,Filling the Tank on
page 5-8, andFuel on page 5-5for more information.
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REAR ACCESS OPEN
This message displays and a chime sounds if the
liftgate or liftglass is open while the ignition is in
ON/RUN. Turn off the vehicle and check the liftgate
and liftglass. SeeLiftgate/Liftglass on page 2-12.
Restart the vehicle and check for the message on
the DIC display.
RIGHT REAR DOOR AJAR
This message displays and a chime sounds if the
passenger side rear door is not fully closed. Stop and
turn off the vehicle, check the door for obstructions,
and close the door again. Check to see if the message
still appears on the DIC.
SERVICE AIR BAG
This message displays if there is a problem with
the airbag system. Have your dealer/retailer inspect
the system for problems. SeeAirbag Readiness Light
on page 3-33andAirbag System on page 1-53for
more information.
SERVICE BRAKE SYSTEM
This message displays if a problem occurs with the
brake system. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicleand 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.
See your dealer/retailer.
SERVICE CHARGING SYS (System)
This message displays if there is a problem with the
battery charging system. Under certain conditions, the
charging system light may also turn on in the instrument
panel cluster. SeeCharging System Light on page 3-36.
The battery will not be charging at an optimal rate and
the vehicle will lose the ability to enter the fuel economy
mode. The vehicle is safe to drive, however you should
have the electrical system checked by your
dealer/retailer.
SERVICE STABILITRAK
If this message displays, it means there may be a
problem with the StabiliTrak®system. If this message
appears, try to reset the system by performing the
following: stop; turn off the engine; then start the engine
again. If this message still comes on, it means there is a
problem. You should see your dealer/retailer for service.
The vehicle is safe to drive, however, you do not have the
benet of StabiliTrak
®, so reduce your speed and drive
accordingly.
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