2007 CHEVROLET TAHOE check engine light

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 564. 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.To program the new additional key do the
following:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key
in the ignition and start the engine. If the
engine will not start, see your dealer
for service.
3. After the engine has started, turn the key to
OFF, and remove the key.
4. Insert the new key to be programmed and turn
it to the RUN position within ve seconds of
removing the original key.
5. The security light will turn off once the key
has been programmed.
6. Repeat Steps 1 through 5 if additional keys
are to be programmed.
If you are driving and the security light comes on
and stays on, you may be able to restart your
engine. Your PASS-Key
®III+ system, however,
may not be working properly and must be serviced
by your dealer.
If you lose or damage your PASS-Key
®III+ key,
see your dealer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
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+/−(Increase/Decrease Temperature):These
buttons select the temperature of the air owing into
the passenger area. Press the + button for warmer
air and press the−button for cooler air.
N(Mode):Press the mode button to manually
change the direction of the airow in your vehicle.
Repeatedly press the button until the desired
mode appears on the display. Multiple presses will
cycle through the delivery selections.
Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages on
your vehicle. The pictures help to 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 the 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
the details show 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 as 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 vehicle’s warning
lights and gages. They can be 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 270for more information.
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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. See
Airbag Readiness Light on page 245.
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 270for
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.
248

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. SeeDIC Warnings and
Messages on page 270for 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 507for 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 516for
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. This may prevent more serious damage
to your vehicle. This system is also designed to
assist your service technician in correctly
diagnosing any malfunction.
253

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 444.
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.
254

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 451.
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 447. 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.
255

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). SeeDIC
Warnings and Messages on page 270andEngine
Oil on page 459for more information.
United StatesCanada
256

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.
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.
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