1999 CHEVROLET CORVETTE service

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If the air bag readiness light stays on after you start the
engine or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to ON. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.
Voltmeter
When the key is in ON with
the engine not running, the
voltmeter shows the voltage
output of your battery.
When the engine is running,
it shows the voltage output
of the charging system.The reading will change as the rate of charge changes
(with engine speed, for example), but if the voltmeter
reads at 9 volts or below, your instrument panel and
other systems may shut down. The Driver Information
Center (DIC) will read LOW VOLTAGE when your
vehicle is at 10 volts or below. Have it checked right
away. Driving with the voltmeter reading at 10 volts or
below could drain your battery and disable your vehicle.
Brake System Warning Light
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.
This light should come on
when you turn the ignition
key to START.

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If it doesn't come on then, have it fixed so it will be
ready to warn you if there's a problem. If this warning
light stays on after you start the engine, the parking
brake may not be set or there could be a brake problem.
Refer to ªParking Brakeº in the Index to see if it is set.
If the parking brake is not set, have your brake system
inspected right away.
If the light comes on while you are driving and you have
a LOW BRAKE FLUID message showing on the DIC,
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 ªTowing
Your Vehicleº in the Index.)
CAUTION:
Your brake system may not be working properly
if the brake warning light is on. Driving with the
brake warning light on can lead to an accident.
If the light is still on after you've 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, the light will come
on when you start your
engine and may stay on
for several seconds.
That's normal.
If the light stays on, turn the ignition to OFF. Or, if the
light comes on when you're driving, stop as soon as
possible and turn the ignition off. Then start the engine
again to reset the system. If the light still stays on, or
comes on again while you're driving, your vehicle needs
service. If the regular brake system warning light isn't
on, you still have brakes, but you don't have anti
-lock
brakes. If the regular brake system warning light is also
on, you don't have anti
-lock brakes and there's a
problem with your regular brakes. See ªBrake System
Warning Lightº earlier in this section.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to ON. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

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2-81 Traction Control System (TCS) Light
This light should come on
briefly as you start the
engine. If the light doesn't
come on then, have it fixed
so it will be ready to warn
you if there's a problem.
If it stays on, or comes on and the DIC shows a
SERVICE TRACTION SYSTEM message when you're
driving, there's a problem with your TCS system and
your vehicle needs service. When this light is on, the
system will not limit wheel spin. Adjust your driving
accordingly. If the driver turns off the Traction Control
System by pressing the button on the console, the TCS
system light will come on and the TRACTION
SYSTEM OFF message will show on the DIC.
Active Handling System Light
If your vehicle has the
optional Active Handling
System, this light will come
on briefly as you start the
engine. If the light does not
come on then, have it fixed
so it will be ready to warn
you if there is a problem.
If it stays on or comes on while you are driving, the
Driver Information Center (DIC) shows a SERVICE
ACTIVE HNDLG message and a chime sounds, there is
a problem with your Active Handling System and your
vehicle needs service. The driver can acknowledge this
message by pressing the RESET button. When the
SERVICE ACTIVE HNDLG message is displayed,
the Active Handling System will not assist you in
controlling the vehicle. You should have the system
serviced as soon as possible. Adjust your
driving accordingly.

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2-83 Malfunction Indicator Lamp
(Check Engine Light)
Your vehicle is equipped
with 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 a while, 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:
Modifications made to the engine, transmission,
exhaust 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 the CHECK ENGINE light to
come on. Modifications 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.

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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 doesn't 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. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center 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 the light stops flashing and remains on steady, see ªIf
the Light Is On Steadyº 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 ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
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. See ªFilling Your Tankº in the Index. 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 (see
ªFuelº in the Index). 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,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix any mechanical or electrical
problems that may have developed.
Engine Oil Pressure Gage
The engine oil pressure
gage shows the engine oil
pressure in psi (pounds per
square inch) or kPa
(kilopascals) when the
engine is running.
Oil pressure should be 20 to 80 psi (140 to 550 kPa).
(In certain situations such as long, extended idles on hot
days, it could read as low as 6 psi (40 kPa) and still be
considered normal.) It may vary with engine speed,
outside temperature and oil viscosity, but readings above
the shaded area show the normal operating range.
Readings in the shaded area tell you that the engine is
low on oil, or that you might have some other oil
problem. See ªEngine Oilº in the Index.
The engine oil pressure can also be displayed using the
GAGES button on the Driver Information Center (DIC).
See ªDriver Information Centerº in the Index.

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CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.
Security Light
This light comes on to
remind you to arm your
theft
-deterrent system. If it
comes on and stays on when
your ignition is on, there
may be a problem with your
theft
-deterrent system.
See ªUniversal Theft
-Deterrentº and ªPASS-Key
Systemº in the Index.
Check Gages Warning Light
This light will come on
briefly when you are
starting the engine. If the
light comes on and stays on
while you are driving, check
your gages to see if they are
in the warning areas.

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2-93 DIC Controls and Displays
Turn on the system by turning the ignition to ON. When
you turn on the ignition, the DIC will be in the mode last
displayed when the engine was turned off. Each DIC
button allows you to scroll through a menu. A blank
page ends each menu.
If a problem is detected, a diagnostic message will appear
on the display. Press RESET to acknowledge any current
warning or service messages. The following pages will
show the messages you can see on the Driver Information
Center (DIC) display by pressing the DIC buttons.
1 FUEL
The FUEL button displays average fuel economy and
instantaneous fuel economy calculated for your specific
driving conditions and range.
Press the FUEL button to display average fuel economy,
such as:

AVERAGE 20.1 MPG or

AVERAGE 5.3 L/100 km