check engine light CHEVROLET AVALANCHE 2007 2.G Owners Manual

PASS-Key®III+ uses a radio frequency
transponder in the key that matches a decoder
in your vehicle.
PASS-Key®III+ Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent
system. PASS-Key
®III+ is a passive theft-deterrent
system. This means you do not have to do anything
special to arm or disarm the system. It works when
you transition the key to RUN, ACCESSORY or
START from the OFF position.
When the PASS-Key
®III+ system senses that
someone is using the wrong key, it prevents
the vehicle from starting. Anyone using a
trial-and-error method to start the vehicle will be
discouraged because of the high number of
electrical key codes.
If the engine does not start and the security light on
the instrument panel cluster comes on when trying
to start the vehicle, the key may have a damaged
transponder. Turn the ignition off and try again.If the engine still does not start, and the key
appears to be undamaged, try another ignition
key. At this time, you may also want to check
the fuse, seeFuses and Circuit Breakers on
page 548. If the engine still does not start with
the other key, your vehicle needs service.
If your vehicle does start, the rst key may be
faulty. See your dealer who can service the
PASS-Key
®III+ to have a new key made.
In an emergency, contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder
to learn the transponder value of a new or
replacement key. Up to nine additional keys may
be programmed for the vehicle. The following
procedure is for programming additional keys only.
If all the currently programmed keys are lost or
do not operate, you must see your dealer or
a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
See your dealer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.
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Warning Lights, Gages,
and Indicators
This part describes the warning lights and gages
on your vehicle. The pictures will help you
locate them.
Warning lights and gages can signal that
something is wrong before it becomes serious
enough to cause an expensive repair or
replacement. Paying attention to your warning
lights and gages could also save you or others
from injury.
Warning lights come on when there may be or
is a problem with one of your vehicle’s functions.
As you will see in the details on the next few
pages, some warning lights come on briey when
you start the engine just to let you know they
are working. If you are familiar with this section,
you should not be alarmed when this happens.Gages can indicate when there may be or is a
problem with one of your vehicle’s functions.
Often gages and warning lights work together
to let you know when there is a problem with your
vehicle.
When one of the warning lights comes on and
stays on when you are driving, or when one of
the gages shows there may be a problem, check
the section that tells you what to do about it.
Please follow this manual’s advice. Waiting to
do repairs can be costly — and even dangerous.
So please get to know your warning lights and
gages. They are a big help.
Your vehicle also has a Driver Information
Center (DIC) that works along with warning lights
and gages. SeeDIC Warnings and Messages
on page 267.
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If, after several seconds, all 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 for service.
{CAUTION:
If the off indicator and the airbag
readiness light ever come on together,
it means that something may be wrong
with the airbag system. If this ever
happens, have the vehicle serviced
promptly, because an adult-size person
sitting in the right front passenger seat
may not have the protection of the frontal
airbag. SeeAirbag Readiness Light
on page 242.
Charging System Light
The charging system
light will come on briey
when you turn on the
ignition, but the engine is
not running, as a check
to show you it is working.
It should go out once the engine is running. If it
stays on, or comes on while you are driving, you
may have a problem with the charging system.
It could indicate that you have problems with the
generator, the generator drive belt, or another
electrical problem. Have it checked right away.
Driving while this light is on could drain your battery.
When this light comes on, the Driver Information
Center (DIC) will also display the SERVICE
BATTERY NOT CHARGING SYSTEM message.
SeeDIC Warnings and Messages on page 267
for more information.
If you must drive a short distance with the light
on, be certain to turn off all your accessories,
such as the radio and air conditioner, to reduce
the drain on your battery.
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Tire Pressure Light
This light will come on
briey when you turn
the ignition to RUN.
This light will also come on when one or more
of your tires are signicantly underinated.
If your vehicle has a Driver Information
Center (DIC), a CHECK TIRE PRESSURE
DIC message will accompany the light. See
DIC Warnings and Messages on page 267for
more information.
Stop and check your tires as soon as it is safe
to do so. If underinated, inate to the proper
pressure. SeeTires on page 492for more
information.This light will ash for 60 seconds and then
turn on solid if a problem is detected with the
Tire Pressure Monitor system.
SeeTire Pressure Monitor System on page 501
for more information.
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.
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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, 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 433.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.
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.
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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 440.
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 436. 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.
252

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 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. When the oil pressure reaches
the low pressure zone, the OIL PRESSURE
LOW STOP ENGINE message will appear
in the Driver Information Center (DIC). See
DIC Warnings and Messages on page 267and
Engine Oil on page 446for more information.
United StatesCanada
253

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.
{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 Light
This light will come on
briey when you start
your engine.
{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.
254

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.
That is a check to be sure the light works.
If it does not come on, be sure to have it xed
so it will be there to warn you if something
goes wrong.
When the light comes on and stays on, it means
that oil is not owing through your engine properly.
You could be low on oil and you might have
some other system problem.
Security Light
This light ashes when
the vehicle security
system is activated.
Fog Lamp Light
The fog lamp light will
come on when the
fog lamps are in use.
The light will go out when the fog lamps are
turned off. SeeFog Lamps on page 218for
more information.
Cruise Control Light
This light comes
on whenever you
set the cruise control.
The light goes out when the cruise control is
turned off. SeeCruise Control on page 212for
more information.
255

CHANGE ENGINE OIL SOON
This message displays when the engine oil needs
to be changed. When you change the engine
oil, be sure to reset the CHANGE ENGINE OIL
SOON message. SeeEngine Oil Life System
on page 449for information on how to reset the
message. This message clears itself after
10 seconds until the next ignition cycle or until the
message is reset. SeeEngine Oil on page 446
andScheduled Maintenance on page 563for
more information.
CHECK TIRE PRESSURE
If your vehicle has a Tire Pressure Monitor (TPM)
system, this message displays when the
pressure in one or more of the vehicle’s tires
need to be checked. This message also displays
LEFT FRONT, RIGHT FRONT, LEFT REAR,
or RIGHT REAR to indicate which tire needs
to be checked. You can receive more than one
tire pressure message at a time. To read the
other messages that may have been sent at thesame time, press the set/reset button or the trip
odometer reset stem. 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 492,Loading Your Vehicle
on page 402, andInation - Tire Pressure
on page 500. The DIC display also shows the
tire pressure values for the front and rear tires
by pressing the vehicle information button.
See “DIC Operation and Displays (With DIC
Buttons)” earlier in this section. If the tire pressure
is low, the low tire pressure warning light comes
on. SeeTire Pressure Light on page 250.DRIVER DOOR OPEN
This message displays and a chime sounds if the
driver’s door is not fully closed and the vehicle
is in a drive gear. 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.
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