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Voltmeter Gage
When your engine is not
running, but the ignition
is on (in the RUN
position), 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. Readings
between the low and high warning zones indicate
the normal operating range.
Readings in the low warning zone may occur
when a large number of electrical accessories are
operating in the vehicle and the engine is left at
an idle for an extended period. This condition
is normal since the charging system is not able to
provide full power at engine idle. As engine
speeds are increased, this condition should correct
itself as higher engine speeds allow the charging
system to create maximum power.You can only drive for a short time with the
reading in either warning zone. If you must drive,
turn off all unnecessary accessories.
Readings in either warning zone indicate a
possible problem in the electrical system. Have
the vehicle serviced as soon as possible.
Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set your parking
brake. The light will stay on if your parking brake
doesn’t release fully. If it stays on after your
parking brake is fully released, it means you have
a brake problem.
Your vehicle’s hydraulic brake system is divided
into two parts. If one part isn’t working, the
other part can still work and stop you. For good
braking, though, you need both parts working well.
If the warning light comes on, there could be a
brake problem. Have your brake system inspected
right away.
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This light should come on briefly when you turn
the ignition key to RUN. If it doesn’t come on then,
have it fixed so it will be ready to warn you if
there’s a problem.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice that the
pedal is harder to push. Or, the pedal may go closer
to the floor. It may take longer to stop. If the light is
still on, have the vehicle towed for service. See
Towing Your Vehicle on page 266.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light
is on. Driving with the brake system
warning light on can lead to an accident.
If the light is still on after you have pulled
off the road and stopped carefully, have
the vehicle towed for service.
Anti-Lock Brake System
Warning Light
With the Anti-Lock
Brake System (ABS),
this light will come
on when you start your
engine and may
stay on for several
seconds, that is normal.
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A chime may also sound when the light comes on.
If the light stays on, or comes on when you are
driving, your vehicle needs service. If the regular
brake system warning light is not on, you still have
brakes, but you do not have anti-lock brakes. If the
regular brake system warning light is also on, you
do not have anti-lock brakes and there is a problem
with your regular brakes. SeeBrake System
Warning Light on page 175earlier in this section.
The ABS warning light should come on briefly
when you turn the ignition key to RUN. If the light
does not come on then, have it fixed so it will
be ready to warn you if there is a problem.
StabiliTrak®Not Ready Light
If your vehicle has the
StabiliTrak®system, this
light will come on
according to the
description table for the
StabiliTrak
®system.
For more information, seeStabiliTrak
®System on
page 235.
You will hear three chimes if the light turns on and
one chime if the light turns off.
StabiliTrak®Indicator Light
If you have the
StabiliTrak®system, this
light will be on or
flashing, according to
the description table for
the StabiliTrak
®system.
For more information, seeStabiliTrak
®System on
page 235.
You will hear three chimes if the light turns on and
one chime if the light turns off.
If this light remains on steady, your vehicle needs
to be taken in for service.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area
your engine is too hot!
It means that your engine coolant has overheated.
If you have been operating your vehicle under
normal operating conditions, you should pull off the
road, stop your vehicle, and turn off the engine
as soon as possible.
SeeEngine Overheating on page 315.
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.
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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:Modi cations 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. Modi cations 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 290.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 misfire condition has
been detected. A misfire 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 flashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to flash, 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 flashing, 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 297.
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.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 293. 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, misfiring, 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 fix any mechanical or electrical
problems that may have developed.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.
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Change Engine Oil Light
This light is displayed
when your vehicle
needs to be serviced.
If your vehicle has a V8 engine and this light is
flashing, it indicates that the oil level is low.
When this light is on steady, your vehicle needs to
be serviced. SeeScheduled Maintenance
(Gasoline Engine) on page 405for more
information.
Once the engine oil has been changed, the
change engine oil light must be reset. Until it is
reset, the light will stay on for a while each time the
engine is started. For more information on
resetting the system, see “How to Reset the
Engine Oil Life System” underEngine Oil
Life System (Gasoline Engine) on page 306.
Security Light
The light will stay on until the engine starts. If the
light flashes, the Passlock®System has entered
a tamper mode. If the vehicle fails to start,
seePasslock
®on page 118.
If the light comes on continuously while driving
and stays on, there may be a problem with
the Passlock
®System. Your vehicle will not be
protected by Passlock®, and you should see your
GM dealer.
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