2006 CHEVROLET TAHOE service

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has 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. See
Gasoline 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.
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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.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 3-55andEngine 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. United States
Canada
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LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door
for obstacles, and close the door again. Check to see if
the message still appears on the DIC. 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.
LOW COOLANT LEVEL
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
If your vehicle has a low coolant level sensor, this
message will appear on the DIC if the engine coolant
level is low. Adding coolant will clear the message.
SeeCooling System on page 5-30. 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.
OIL LIFE RESET
This message will appear on the DIC for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-52andEngine Oil
on page 5-15for more information.
OIL PRESSURE LOW
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on the
Driver Information Center (DIC), stop the vehicle
as soon as possible. Do not drive the vehicle until
the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-15for more information.
If low oil pressure levels occur, this message will
be displayed on the DIC and a chime will sound. Stop
the vehicle as soon as safely possible and do not
operate it until the cause of the low oil pressure has
been corrected. Check your oil as soon as possible
and have your vehicle serviced by your GM dealer.
SeeEngine Oil on page 5-15.
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PASSENGER DOOR AJAR
If the passenger’s door is not fully closed, this message
will appear on the display and you will hear a chime.
Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if
the message still appears on the DIC. 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.
REAR ACCESS OPEN
If the liftgate is open while the ignition is in RUN, this
message will appear on the DIC and you will hear
a chime. Turn off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the
DIC display. 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.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode. SeeEngine
Overheating on page 5-28for further information.
This message will also display when the vehicle’s engine
power is reduced. Reduced engine power can affect
the vehicle’s ability to accelerate. If this message is on,
but there is no reduction in performance, proceed to
your destination. The performance may be reduced the
next time the vehicle is driven. The vehicle may be
driven at a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime this
message stays on, the vehicle should be taken to
your GM dealer for service as soon as possible.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeFuses and Circuit Breakers on
page 5-109. If the message returns after replacing the
fuse, see your GM dealer for service.
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RIGHT REAR DOOR AJAR
If the passenger’s side rear door is not fully closed, this
message will appear on the display and you will hear
a chime. Stop and turn off the vehicle, check the door for
obstacles, and close the door again. Check to see if
the message still appears on the DIC. 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.
SERVICE 4WD (Four-Wheel-Drive or
All-Wheel-Drive)
If a problem occurs with the four-wheel-drive system or
the all-wheel-drive system, this message will appear
on the DIC. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicle
and check for the message on the DIC display. If
the message is still displayed or appears again when
you begin driving, the four-wheel-drive system or
all-wheel-drive system needs service. See your
GM dealer. 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.
SERVICE AIR BAG
If there is a problem with the airbag system, this
message will be displayed on the DIC. Have your
GM dealer inspect the system for problems. SeeAirbag
Readiness Light on page 3-37andAirbag System on
page 1-74for more information. 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.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and 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 GM dealer. 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.
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SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the
DIC. Under certain conditions, the battery warning light
may also turn on in the instrument panel cluster.
SeeBattery Warning Light on page 3-39. 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 GM dealer. 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.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. See your GM dealer.
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.
SERVICE STABILITY
If you ever see the SERVICE STABILITY message, it
means there may be a problem with your StabiliTrak®
system. If you see this message, try to reset the system.
Stop; turn off the engine; then start the engine again.
If the SERVICE STABILITY message still comes
on, it means there is a problem. You should see your
GM dealer for service. The vehicle is safe to drive,
however, you do not have the benet of StabiliTrak
®,so
reduce your speed and drive accordingly. 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.
SERVICE TIRE MONITOR
If your vehicle has the tire pressure monitor system,
this message will be displayed if one or more of the
tire monitor sensors have malfunctioned or if all of the
tire monitor sensors have not been programmed
successfully. See your GM dealer. 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. The message will
reappear at each ignition cycle until the system has
been serviced. See your GM dealer.
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STABILITY SYS (System) ACTIVE
You may see the STABILITY SYS ACTIVE message on
the DIC. It means that an advanced computer-controlled
system has come on to help your vehicle continue to
go in the direction in which you are steering. StabiliTrak
®
activates when the computer senses that your vehicle
is just starting to spin, as it might if you hit a patch of
ice or other slippery spot on the road. When the system
activates, you may hear a noise or feel a vibration in
the brake pedal. This is normal. When the STABILITY
SYS ACTIVE message is on, you should continue
to steer in the direction you want to go. The system is
designed to help you in bad weather or other difficult
driving situations by making the most of whatever road
conditions will permit.
STABILITY SYS (System) DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the StabiliTrak®button, or when
the stability control has been automatically disabled.
To limit wheel spin and realize the full benets of
the stability enhancement system, you should normally
leave StabiliTrak
®on. However, you should turn
StabiliTrak®off if your vehicle gets stuck in sand,
mud, ice, or snow and you want to rock your vehicle
to attempt to free it, or if you are driving in extreme
off-road conditions and require more wheel spin.SeeIf Your Vehicle is Stuck in Sand, Mud, Ice or Snow
on page 4-46. To turn the StabiliTrak
®system back
on, press the StabiliTrak®button again.
There are several conditions that can cause this
message to appear.
One condition is overheating, which could occur if
StabiliTrak®activates continuously for an extended
period of time.
The message will also be displayed if the brake
system warning light is on. SeeBrake System
Warning Light on page 3-41.
The message could be displayed if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
If an engine or vehicle related problem has been
detected and the vehicle needs service, the
message will appear. See your GM dealer.
The message will also appear if the vehicle is
shifted into 4LO.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
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