2008 CHEVROLET SILVERADO check engine light

For example, if the lock button and then the remote
start buttons are pressed again after the vehicle
has been running for ve minutes, 10 minutes are
added, allowing the engine to run for 15 minutes.
The additional ten minutes are considered a second
remote vehicle start.
Once two remote starts, or a single remote start with
one time extension has been done, the vehicle must be
started with the key.
After the key is removed from the ignition, the vehicle
can be remote started again.
The vehicle cannot be remote started if the key is
in the ignition, the hood is not closed, or if there is
an emission control system malfunction and the
check engine light comes on.
Also, the engine will turn off during a remote vehicle
start if the coolant temperature gets too high or if the
oil pressure gets low.Vehicles that have the remote vehicle start feature are
shipped from the factory with the remote vehicle start
system enabled. The system may be enabled or disabled
through the DIC. See “REMOTE START” underDIC
Vehicle Customization (With DIC Buttons) on page 3-76
for additional information. If your vehicle does not have
DIC buttons, see your dealer/retailer to enable or disable
the remote vehicle start system.
Remote Start Ready
If your vehicle does not have the remote vehicle start
feature, it may have the remote start ready feature.
This feature allows your dealer/retailer to add the
manufacturer’s remote vehicle start feature.
See your dealer/retailer if you would like to add the
manufacturer’s remote vehicle start feature to your
vehicle.
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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 5-125. 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/retailer 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 10 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/retailer
or a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
See your dealer/retailer 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:
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/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the new key to be programmed and turn it to
the ON/RUN position within ve seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to
be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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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 3-66for
more information.
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Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol.
The system checks the airbag’s electrical system for
malfunctions. The light tells you if 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 1-69.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. The light
should go out and the
system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away.
The airbag readiness light should ash for a few seconds
when you start the engine. If the light does not come on
then, have it xed immediately. If there is a problem with
the airbag system, an airbag Driver Information Center
(DIC) message may also come on. SeeDIC Warnings
and Messages on page 3-66for more information.
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Charging System Light
This light will come on
briey when you turn on
the ignition key, 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 driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-66
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 you must drive a short distance with the light on,
be certain to turn off all the accessories, such as the
radio and air conditioner.
Voltmeter Gage
Your vehicle may have a
voltmeter gage.
When the ignition is on, this gage indicates the
battery voltage.
When the engine is running, this 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. If the vehicle is operating outside
the normal operating range, the charging system light
will come on. SeeCharging System Light on page 3-45
for more information. The voltmeter gage may also
read lower when in fuel economy mode. This is normal.
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Tire Pressure Light
This light comes on briey
when the engine is started.
This light will also come on when one or more of your
tires are signicantly underinated.
A tire pressure message in the Driver Information
Center (DIC), may accompany the light. SeeDIC
Warnings and Messages on page 3-66for 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 5-68for more information.
If a problem is detected with the Tire Pressure Monitor
System, this light will ash for approximately
60 seconds and then stay on solid for the remainder of
the ignition cycle. SeeTire Pressure Monitor System
on page 5-78for 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 makes
sure 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 an OBD II
problem and service
is required.
Malfunctions often are indicated by the system before
any problem is apparent. This can 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 a while, 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.
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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 5-4.
This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also 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
your vehicle. Diagnosis and service might be
required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
If the Light is Flashing
The following can prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 5-10.
The diagnostic system can determine if the fuel
cap has been left off or improperly installed.
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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.
Did you just drive through a deep puddle of water?
If so, your 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.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 5-6. Poor fuel quality
causes the engine not to run as efficiently as
designed. You might 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 might 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/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
might 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 the battery or if the battery
has run down. The diagnostic system is designed to
evaluate critical emission control systems during normal
driving. This can 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/retailer can prepare the vehicle for inspection.
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