check engine light CHEVROLET SILVERADO 2006 1.G Owners Manual

If you set off the alarm by accident, turn off the alarm by
pressing unlock on the remote keyless entry transmitter
or by placing the key in the ignition and turning it
to START.
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
RKE transmitter.
3. Get out of the vehicle, close the door and wait for
the security light to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
If the alarm does not sound when it should, but the
vehicle’s headlamps ash, check to see if the horn
works. The horn fuse may be blown. To replace the
fuse, seeFuses and Circuit Breakers on page 5-126.
If the alarm does not sound or the vehicle’s headlamps
do not ash, see your dealer for service.
Passlock®
Your vehicle is equipped with the
Passlock®theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder is
turned with a valid key. If a correct key is not used or the
ignition lock cylinder is tampered with, fuel is disabled.
If the engine stalls and the security light ashes,
wait until the light stops ashing before trying to restart
the engine. Remember to release the key from
START as soon as the engine starts.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®at this
time. You may also want to check the fuse. See
Fuses and Circuit Breakers on page 5-126. See your
dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-6.
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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. See
DIC Warnings and Messages on page 3-54.
3-30

Battery Warning Light
If this light is displayed
when the engine is
running, you may have
a problem with your
charging system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the light stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories,
such as the radio and the air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition
is in RUN, this gage shows
your battery’s state of
charge in DC volts.
When the engine is running, the 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. Readings between the low and
high warning zones indicate the normal operating
range. The voltmeter gage may also read lower when
in fuel economy mode. This is normal.
3-39

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 5-4.
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 5-10.
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 5-6. 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.
3-46

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
3-47

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 3-54andEngine Oil
(Gasoline Engine) on page 5-20.
{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 3-10for more
information.
3-48

This message is an additional reminder to the Safety
Belt Reminder Light in the instrument panel cluster.
SeeSafety Belt Reminder Light on page 3-33for 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.
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 (Gasoline Engine) on page 5-23,Engine
Oil (Gasoline Engine) on page 5-20, andScheduled
Maintenance (Gasoline Engine) on page 6-4for more
information.
CHARGING SYSTEM FAILURE
On some vehicles, if there is a problem with the
generator and battery charging system, this message
will appear on the DIC, a chime will sound, and the
battery warning light on the instrument panel cluster will
come on. Driving with this problem could drain your
battery. Turn off all unnecessary accessories. Stop and
turn off the vehicle as soon as it is safe to do so.
Have the electrical system checked by your GM dealer
immediately. SeeBattery Warning Light on page 3-39
andVoltmeter Gage on page 3-39for more information.
CHECK OIL LEVEL
If your vehicle has an oil level sensor, and the oil level
in the vehicle is low, this message will appear on
the DIC. Check the oil level and correct it as necessary.
You may need to let the vehicle cool or warm up and
cycle the ignition to be sure this message will clear.
Once the problem is corrected, 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. SeeEngine Oil (Gasoline
Engine) on page 5-20for additional information.
3-56

FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. 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. SeeLow Fuel Warning Light on page 3-50,
Fuel Gage on page 3-50, andFuel on page 5-6.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-5. 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.
LEFT REAR DOOR AJAR (Crew Cab)
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 to the coolant recovery
tank will clear the message. SeeCooling System
on page 5-40. 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.
3-58

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 5-37for 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.
RIGHT REAR DOOR AJAR (Crew Cab)
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)
If a problem occurs with the four-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 needs service. See your
GM dealer.
SERVICE AIRBAG
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 3-33andAirbag System on
page 1-71for 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.
3-60