light CHEVROLET IMPALA 2008 9.G Service Manual

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 1-54.
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 if the airbag
readiness light stays on after you start your
vehicle.
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 3-52for more information.
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Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system.
Your instrument panel has a passenger airbag status
indicator.
When you start the vehicle, the passenger airbag status
indicator will light ON and OFF, or the symbol for on
and off, for several seconds as a system check. If you
use remote start to start your vehicle from a distance,
if equipped, you may not see the system check.
Then, after several more seconds, the status indicator
will light either ON or OFF, or either the on or off symbol
to let you know the status of the right front passenger’s
frontal airbag.If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger’s frontal airbag is enabled (may inate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger’s seat, it means that the
passenger sensing system has not turned off
the passenger’s frontal airbag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger’s
airbag inates. This is because the back of the
rear-facing child restraint would be very close
to the inating airbag. Do not use a rear-facing
child restraint in the right front passenger’s seat
if the airbag is turned on. United States
Canada
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{CAUTION:
Even though the passenger sensing system is
designed to turn off the right front passenger’s
frontal airbag if the system detects a rear-facing
child restraint, no system is fail-safe, and no
one can guarantee that an airbag will not deploy
under some unusual circumstance, even
though it is turned off. We recommend that
rear-facing child restraints be secured in the
rear seat, even if the airbag is off.
If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger’s frontal
airbag. SeePassenger Sensing System on page 1-62
for more on this, including important safety information.If, after several seconds, both 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/retailer for service.
{CAUTION:
If the airbag readiness light in the instrument
panel cluster ever comes on and stays on,
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’s seat may not have the protection
of the airbag(s). SeeAirbag Readiness Light
on page 3-31for more on this, including
important safety information.
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Charging System Light
This 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. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-52
for more information. This light could indicate that you
have problems with a generator drive belt, or another
electrical problem. Have it checked right away.
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.
Brake System Warning Light
Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not 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 is a brake problem.
Have your brake system inspected right away.
This light should come on briey when the engine is
started. If it does not come on then, have it xed so it
will be ready to warn you if there is a problem.
United StatesCanada
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When the ignition is on, the brake system warning light
will also come on when you set your parking brake.
The light will stay on if your parking brake does
not release fully. If it stays on after your parking brake is
fully released, it means you have a brake 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
oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. SeeTowing Your
Vehicle on page 4-26.
{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.
Antilock Brake System
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light will come
on briey when you
start the engine.
That is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If the ABS light stays on, turn the ignition off, if the light
comes on when you are driving, stop as soon as it
is safely possible and turn the ignition off. Then start the
engine again to reset the system. If the ABS light still
stays on, or comes on again while 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 antilock brakes. If the regular brake system
warning light is also on, you do not have antilock brakes
and there is a problem with your regular brakes.
SeeBrake System Warning Light on page 3-34
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-52for all
brake related DIC messages.
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Traction Control System (TCS)
Warning Light
This warning light should
come on briey when the
engine is started.
If the warning light does not come on then, have it xed
so it will be ready to warn you if there is a problem.
If it stays on, or comes on when you are driving
a SERVICE TRACTION CONTROL message will appear
in the Driver Information Center (DIC). This indicates
that there may be a problem with your traction control
system and your vehicle may need service. When
this warning light is on and the SERVICE TRACTION
CONTROL message appears on the DIC, the system
will not limit wheel spin. Adjust your driving accordingly.
If the traction control system is manually turned off,
this light will come on and the TRACTION
CONTROL OFF message will appear on the DIC.When the system is active, the light will ash while the
system is limiting wheel spin or assisting you in
controlling the vehicle. You may also feel or hear the
system working. This is normal.
SeeTraction Control System (TCS) on page 4-6and
DIC Warnings and Messages on page 3-52for
more information.
Electronic Stability Control
Indicator Light
This warning light should
come on briey when the
engine is started.
If the warning light does not come on then, have it xed
so it will be ready to warn you if there is a problem.
This light may come on after you rst start to drive and
the STABILITRAK NOT READY message will appear
in the Driver Information Center (DIC). SeeElectronic
Stability Control on page 4-7for more information.
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If the light stays on, or comes on when you are driving
a SERVICE STABILITRAK message will appear in
the DIC. This indicates that there may be a problem with
the Electronic Stability Control (ESC) system and your
vehicle may need service. When this warning light
is on and the SERVICE STABILITRAK message
appears on the DIC, the ESC system will not assist you
in controlling the vehicle. Adjust your driving accordingly.
When the system is active, the light will ash while
the system is assisting you in controlling the vehicle.
You may also feel or hear the system working.
This is normal.
SeeElectronic Stability Control on page 4-7and
DIC Warnings and Messages on page 3-52for
more information.Engine Coolant Temperature
Warning Light
The engine coolant
temperature warning light
will come on when the
engine has overheated.
If this happens you should pull over and turn off the
engine as soon as possible. SeeEngine Overheating
on page 5-29for more information.
Notice:Driving with the engine coolant temperature
warning light on could cause your vehicle to
overheat. SeeEngine Overheating on page 5-29.
Your vehicle could be damaged, and it might not be
covered by your warranty. Never drive with the
engine coolant temperature warning light on.
This light will also come on briey when starting your
vehicle. If it does not, have your vehicle serviced.
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the
gage pointer moves towards the “H” (United States)
or the shaded in thermostat (Canada), it means that your
engine coolant has overheated. If you have been
operating your vehicle under normal driving conditions,
you should pull off the road, stop your vehicle and
turn off the engine as soon as possible.
SeeEngine Overheating on page 5-29for more
information.
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 3-52for 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 5-54for 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 5-63for more information. United States
Canada
3-38

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
make 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 a problem and service is required.
Malfunctions often will be 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.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 5-3.
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 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.
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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 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/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. 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.
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