2008 CHEVROLET AVALANCHE service

OnStar®System
OnStar uses several innovative technologies and live
advisors to provide you with a wide range of safety,
security, information, and convenience services. If your
airbags deploy, the system is designed to make an
automatic call to OnStar Emergency advisors who can
request emergency services be sent to your location.
If you lock your keys in the vehicle, call OnStar at
1-888-4-ONSTAR and they can send a signal to unlock
your doors. If you need roadside assistance, press
the OnStar button and they can contact Roadside
Service for you.OnStar service is provided to you subject to the OnStar
Terms and Conditions. You may cancel your OnStar
service at any time by contacting OnStar. A complete
OnStar Owner’s Guide and the OnStar Terms and
Conditions are included in the vehicle’s OnStar
Subscriber glove box literature. For more information,
visit onstar.com or onstar.ca, contact OnStar at
1-888-4-ONSTAR (1-888-466-7827) or TTY
1-877-248-2080, or press the OnStar button to speak
with an OnStar advisor 24 hours a day, 7 days a week.
Not all OnStar features are available on all vehicles.
To check if your vehicle is equipped to provide the
services described below, or for a full description of
OnStar services and system limitations, see the OnStar
Owner’s Guide in your glove box or visit onstar.com.
OnStar Services
For new vehicles with OnStar, the Safe & Sound Plan,
or the Directions & Connections Plan is included for
one year from the date of purchase. You can extend
this plan beyond the rst year, or upgrade to the
Directions & Connections Plan. For more information,
press the OnStar button to speak with an advisor. Some
OnStar services (such as Remote Door Unlock or Stolen
Vehicle Location Assistance) may not be available until
you register with OnStar.
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Available Services with Safe & Sound Plan

Automatic Notication of Airbag Deployment
Advanced Automatic Crash Notication (AACN)
(If equipped)
Link to Emergency Services
Roadside Assistance
Stolen Vehicle Location Assistance
AccidentAssist
Remote Door Unlock/Vehicle Alert
OnStar Vehicle Diagnostics
GM Goodwrench On Demand Diagnostics
OnStar Hands-Free Calling with 30 complimentary
minutes
OnStar Virtual Advisor (U.S. Only)
Available Services included with
Directions & Connections Plan

All Safe and Sound Plan Services
Driving Directions - Advisor delivered or OnStar
Turn-by-Turn Navigation (If equipped)
RideAssist
Information and Convenience Services
OnStar Hands-Free Calling
OnStar Hands-Free Calling allows eligible OnStar
subscribers to make and receive calls using voice
commands. Hands-Free Calling is fully integrated into the
vehicle, and can be used with OnStar Pre-Paid Minute
Packages. Hands-Free Calling may also be linked to
a Verizon Wireless service plan in the U.S. or a Bell
Mobility service plan in Canada, depending on eligibility.
To nd out more, refer to the OnStar Owner’s Guide
in the vehicle’s glove box, visit www.onstar.com or
www.onstar.ca, or speak with an OnStar advisor by
pressing the OnStar button or calling 1-888-4-ONSTAR
(1-888-466-7827).
OnStar Virtual Advisor
OnStar Virtual Advisor is a feature of OnStar
Hands-Free Calling that uses your minutes to access
location-based weather, local traffic reports, and stock
quotes. By pressing the phone button and giving a few
simple voice commands, you can browse through the
various topics. See the OnStar Owner’s Guide for more
information (Only available in the continental U.S.).
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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 3-118for
more information.
On some vehicles, you may have to hold the button for
a few seconds and give the command “ONSTAR” to
activate the OnStar Hands-Free Calling.
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
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.
Location information about your vehicle is only available
if the GPS satellite signals are unobstructed and
available.
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
Increase the radio volume if you cannot 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.
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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.
Universal Home Remote System
Operation (With Three Round LED)
This vehicle may have the Universal Home Remote
System. If there are three round Light Emitting
Diode (LED) indicator lights above the Universal
Home Remote buttons, follow the instructions below.
This system provides a way to replace up to three
remote control transmitters used to activate devices
such as garage door openers, security systems,
and home automation devices.
Do not use this system with any garage door opener
that does not have the stop and reverse feature.
This includes any garage door opener model
manufactured before April 1, 1982.
Read the instructions completely before attempting to
program the transmitter. Because of the steps involved,
it may be helpful to have another person assist with
programming the transmitter.
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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 3-59.
Battery Run-Down Protection
This feature shuts off the dome lamps if they are left on
for more than 10 minutes when the ignition is in LOCK.
This will help prevent the battery from running down.
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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.
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 3-59for
more information.
Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system.
Your overhead console 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.
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).United States
Canada
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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 3-35for more on this, including
important safety information.
Charging System Light
This light will come on
briey when you turn
on the ignition key, 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 driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-59for more
information. This light could indicate that there are
problems with a generator drive belt, or that there is an
electrical problem. Have it checked right away. If you
must drive a short distance with the light on, be certain
to turn off all the accessories, such as the radio and air
conditioner.
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Voltmeter Gage
When your engine is not
running, but the ignition is
on, this gage shows
the battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery for
improved fuel economy and battery life. 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 gage may also read low during the fuel economy
mode, this is normal.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 full power. If there
is a problem with the battery charging system, this light
will come on or the SERVICE BATTERY CHARGING
SYSTEM DIC message will display. SeeDIC Warnings
and Messages on page 3-59andCharging System Light
on page 3-38for more information.
Brake System Warning Light
With the ignition on, the brake system warning light
will come on when you set the parking brake. If you
try to drive with the parking brake engaged, a chime
will sound when the vehicle speed is greater than
5 mph (8 km/h).
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 and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
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