2009 GMC ENVOY engine

Airbag Readiness Light
The system checks the airbag’s electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check
includes the airbag sensor, the pretensioners, the airbag
modules, the wiring and the crash sensing and
diagnostic module. For more information on the airbag
system, seeAirbag System on page 1-55.
The airbag readiness light
ashes for a few seconds
when the engine is
started. If the light does
not come on then, have it
xed immediately.{CAUTION:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inate in a crash, or they could even inate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also come
on. SeeDIC Warnings and Messages on page 3-51
for more information.
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If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may be a
problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{CAUTION:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. To help avoid injury to
yourself or others, have the vehicle serviced right
away. SeeAirbag Readiness Light on page 3-31
for more information, including important safety
information.
Charging System Light
This light comes on briey
when the ignition key is
turned to START, but
the engine is not running,
as a check to show it
is working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it
stays on, or comes on while driving, there could be a
problem with the charging system. A charging system
message in the Driver Information Center (DIC) can also
appear. SeeDIC Warnings and Messages on page 3-51
for more information. This light could indicate that
there are problems with a generator drive belt, or that
there is an electrical problem. Have it checked right
away. If the vehicle must be driven a short distance with
the light on, turn off accessories, such as the radio
and air conditioner.
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Voltmeter Gage
When your engine is not
running, but the ignition is
on, this gage displays
the battery voltage in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading. This is normal. Readings between the low and
high warning zones indicate the normal operating range.
The voltmeter gage may also read lower when in fuel
economy mode. This is normal.Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left idling for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
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Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briey when the engine
is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the light
comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on,
or comes on again while driving, the vehicle needs
service. If the regular brake system warning light is
not on, the vehicle still has brakes, but not antilockbrakes. If the regular brake system warning light is also
on, the vehicle does not have antilock brakes and
there is a problem with the regular brakes. SeeBrake
System Warning Light on page 3-35.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-51for all
brake related DIC messages.
StabiliTrak®Service Light
This light will come on
briey when the engine
is started.
This light will come on if a problem is detected in the
StabiliTrak
®system.
For more information seeStabiliTrak
®System on
page 4-6.
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StabiliTrak®Indicator Light
This warning light should
come on briey when the
engine is started.
During most driving conditions, this light will not come
on. If the StabiliTrak
®System is actively controlling
the stability and/or traction of the vehicle, this light will
ash. This is normal.
This light will come on if any portion of the system has
been manually turned off or a problem is detected
in the system.
If your vehicle has a Driver Information Center, a
message will appear also, seeDIC Warnings and
Messages on page 3-51andStabiliTrak
®System on
page 4-6for more information.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves into the red area, it means that
the 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.
SeeEngine Overheating on page 5-30for more
information.
United StatesCanada
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Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when the
engine is started and
provides information about
tire pressures and the
Tire Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information Center
(DIC), can accompany the light. SeeDIC Warnings and
Messages on page 3-51for more information. Stop and
check the tires as soon as it is safe to do so. If a tire is
underinated, inate to the proper pressure. SeeTires on
page 5-53for more information.
When the Light Flashes First and Then is
On Steady
This indicates that there could be a problem with the
Tire Pressure Monitor System. The light ashes
for about a minute and stays on steady for the remainder
of the ignition cycle. This sequence repeats with
every ignition cycle. SeeTire Pressure Monitor System
on page 5-63for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
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This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
working. If it does not,
have the vehicle serviced
by your dealer/retailer.
If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the 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 the vehicle warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
the vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a
required Emission Inspection/Maintenance test.
SeeAccessories and Modifications on page 5-3.
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This light 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 the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
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 key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer for service as soon
as possible.Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-8. The diagnostic system can
determine if the fuel cap has been left off or
improperly 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.
If the vehicle has been driven through a deep
puddle of water, the 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.
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