2006 GMC YUKON light

Malfunction Indicator Lamp
Check Engine Light
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 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 awhile, 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: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 may cause this light to come on.
Modications 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. SeeAccessories
and Modifications on page 5-3.
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 does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
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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 “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 your vehicle.
Turn the key 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 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. 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 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.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 5-5. 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, misring,
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.
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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 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.
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).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.United States
Canada
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A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem
causing low oil pressure. Check your oil as soon as
possible. See “OIL PRESSURE LOW” underDIC
Warnings and Messages on page 3-56andEngine Oil
on page 5-15.
{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.
Security Light
This light ashes when the
vehicle security system is
activated.
Cruise Control Light
This light comes on
whenever you set your
cruise control.
The light will go out when the cruise control is
turned off. SeeCruise Control on page 3-11for
more information.
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Highbeam On Light
This light will come on
when the high-beam
headlamps are in use.
SeeHeadlamp High/Low-Beam Changer on page 3-8.
Four-Wheel-Drive Light
The four-wheel-drive
indicator will light up
when the vehicle is in
four-wheel drive.
SeeFour-Wheel Drive on page 2-26for more
information.
Tow/Haul Mode Light
This light is displayed
when the Tow/Haul mode
has been activated.
For more information, seeTowing a Trailer on
page 4-60.
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Fuel Gage
The fuel gage, when the ignition is on, tells you about
how much fuel you have left in your tank.
The gage will rst indicate empty before you are out of
fuel, and you should get more fuel as soon as possible.
When the fuel tank is low, the FUEL LEVEL LOW
message will appear. SeeDIC Warnings and Messages
on page 3-56.Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to ll up than the
fuel 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 goes back to empty when you turn off
the ignition.
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 5-4. United States
Canada
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DIC Warnings and Messages
Warning messages are displayed on the Driver
Information Center (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.
If there is more than one message that needs to
be displayed, they will appear one after another. Some
messages may not require immediate action, but
you should press any of the four DIC buttons on the
steering wheel to acknowledge that you received
the messages and clear them from the display. If your
vehicle does not have DIC buttons on the steering
wheel, press the trip odometer reset stem located on
the instrument panel cluster to acknowledge messages
and clear them 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. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
BATTERY NOT CHARGING
On some vehicles, 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 by your GM dealer
as soon as possible. SeeBattery Warning Light on
page 3-40andVoltmeter Gage on page 3-41. Pressing
any of the four DIC buttons will acknowledge the
message and clear it from the DIC display. If your
vehicle does not have the four DIC buttons, pressing
the trip odometer reset stem will acknowledge the
message and clear it from the DIC display.
BUCKLE PASSENGER
If your vehicle has the passenger sensing system,
this message reminds you to buckle the passenger’s
seat belt. SeePassenger Sensing System on page 1-82.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is buckled, the
passenger’s seat belt is unbuckled with the passenger
airbag enabled, and the vehicle is in motion. You should
have the passenger buckle their seat belt.
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This reminder will be repeated if the ignition is on,
the vehicle is in motion, the driver is buckled and the
passenger is still unbuckled, and the passenger airbag is
enabled. If the passenger’s seat belt is already
buckled, this message and chime will not come on.
Pressing any of the four DIC buttons will acknowledge
the message and clear it from the DIC display.
If your vehicle does not have the four DIC buttons,
pressing the trip odometer reset stem will acknowledge
the message and clear it from the DIC display.
BUCKLE SEATBELT
If your vehicle has the passenger sensing system, this
message reminds you to buckle the driver’s seat
belt. SeePassenger Sensing System on page 1-82.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is unbuckled,
and the vehicle is in motion. You should buckle
your seat belt.
If the driver remains unbuckled when the ignition is on
and the vehicle is in motion, the reminder will be
repeated. If the driver’s seat belt is already buckled,
this message and chime will not come on.This message is an additional reminder to the Safety
Belt Reminder Light in the instrument panel cluster.
SeeSafety Belt Reminder Light on page 3-37.
Pressing any of the four DIC buttons will acknowledge
the message and clear it from the DIC display.
If your vehicle does not have the four DIC buttons,
pressing the trip odometer reset stem will acknowledge
the message and clear it from the DIC display.
CHANGE ENGINE OIL
This message is displayed when the engine oil needs
to be changed. When you change the engine oil,
be sure to reset the CHANGE ENGINE OIL message.
SeeEngine Oil Life System on page 5-18for information
on how to reset the message. This message will clear
itself after 10 seconds until the next ignition cycle or until
the message is reset. SeeEngine Oil on page 5-15
andScheduled Maintenance on page 6-4for more
information.
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