2008 CHEVROLET IMPALA service

OnStar Steering Wheel Controls
Your vehicle may have a Talk/Mute button that can be
used to interact with OnStar Hands-Free Calling.
SeeAudio Steering Wheel Controls on page 3-86
for more information.
On some vehicles, you may have to hold the button for
a few seconds and give the command “ONSTAR” in
order to activate the OnStar Hands-Free Calling feature.
On some vehicles, the mute button can be used to
dial numbers into voicemail systems, or to dial phone
extensions. See the OnStar Owner’s Guide for
more information.
How OnStar Service Works
In order to provide you with OnStar services, your
vehicle’s OnStar system has the capability of recording
and transmitting vehicle information. This information
is automatically sent to an OnStar Call Center at
the time of an OnStar button press, Emergency button
press or if your airbags or AACN system deploys.The vehicle information usually includes your GPS
location and, in the event of a crash, additional
information regarding the accident that your vehicle has
been involved in (e.g. the direction from which your
vehicle was hit). When you use the Virtual Advisor
feature of OnStar Hands-Free Calling, your vehicle
also sends OnStar your GPS location so that we can
provide you with location-based services.
OnStar service cannot work unless your vehicle is in a
place where OnStar has an agreement with a wireless
service provider for service in that area. OnStar
service also cannot work unless you are in a place
where the wireless service provider OnStar has hired for
that area has coverage, network capacity and reception
when the service is needed, and technology that is
compatible with the OnStar service. Not all services
are available everywhere, particularly in remote
or enclosed areas, or at all times.
OnStar service that involves location information about
your vehicle cannot work unless GPS satellite signals
are unobstructed and available in that place as well.
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Your vehicle must have a working electrical system
(including adequate battery power) for the OnStar
equipment to operate. There are other problems OnStar
cannot control that may prevent OnStar from providing
OnStar service to you at any particular time or place.
Some examples are damage to important parts of your
vehicle in an accident, hills, tall buildings, tunnels,
weather or wireless phone network congestion.
Your Responsibility
You may need to increase the volume of your radio
to hear the OnStar advisor. If the light next to the OnStar
buttons is red, this means that your system is not
functioning properly and should be checked by your
dealer/retailer. If the light appears clear (no light
is appearing), your OnStar subscription has expired.
You can always press the OnStar button to conrm that
your OnStar equipment is active.
Universal Home Remote System
The Universal Home Remote System provides a way to
replace up to three hand-held Radio-Frequency (RF)
transmitters used to activate devices such as garage
door openers, security systems, and home lighting.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
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Reading Lamps
The vehicle has reading lamps that also act as the
dome lamp. Press the button to turn them on and off.
Mirror Reading Lamps
Your vehicle has reading lamps on the rearview mirror.
Push the button to turn the reading lamps on and off.
Electric Power Management
The vehicle has Electric Power Management (EPM)
that estimates the battery’s temperature and state
of charge. It then adjusts the voltage for best
performance and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up or
down. This is normal. If there is a problem, an alert
will be displayed.The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles.
This is because the generator (alternator) may not be
spinning fast enough at idle to produce all the power that
is needed for very high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at
high speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator’s output
and the vehicle’s electrical needs. It can increase
engine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands of
some accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as Battery Saver Active or
Service Battery Charging System. If this message is
displayed, it is recommended that the driver reduce the
electrical loads as much as possible. SeeDIC Warnings
and Messages on page 3-52.
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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 1-54.
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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{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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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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