2002 CHEVROLET AVALANCHE service

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4HI: Use 4HI when you need extra traction, such as
on snowy or icy roads or in most off
-road situations.
This setting also engages your front axle to help drive
your vehicle. This is the best setting to use when
plowing snow.
4LO: This setting also engages your front axle and
delivers extra torque. You may never need 4LO. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off
-road in deep sand, deep mud,
deep snow and climbing or descending steep hills.
CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the transmission
is in PARK (P). You or someone else could be
seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL. See ªParking Brakeº in the Index.
NEUTRAL: Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle.
See ªRecreational Vehicle Towingº or ªTowing
Your Vehicleº in the Index for more information.
Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on
briefly when you turn on the ignition and one will stay
on. If the lights do not come on, you should take your
vehicle to your dealer for service. An indicator light will
flash while the transfer case is being shifted. It will
remain illuminated when the shift is complete. If for
some reason the transfer case cannot make a requested
shift, it will return to the last chosen setting.
If the SERVICE 4WD message stays on, you
should take your vehicle to your dealer for service.
See ªService 4WDº in the Index for further information.

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Auxiliary Roof Mounted Lamp Switch
(If Equipped)
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualified service
center to install an auxiliary roof lamp.
This button is located
on the center of the
instrument panel near
the comfort controls.
When the button wiring is connected to an auxiliary
roof
-mounted lamp, pressing the button will activate
the lamp and illuminate an indicator light near the
button. Pressing the button again will turn off the
roof mounted lamp.
If your vehicle has this button, your vehicle may have
the snow plow prep package. For further information
see ªSnow Plow Prep Packageº in the Index.
Cargo Lamps
You can use the cargo lamps if you need more light in the
cargo area of your vehicle or in the top
-box storage units.
Press this button, located
on the instrument panel to
turn the cargo lamps on.
Press the button again to
turn it off.
A message in the message
center will come on and
display CARGO LAMP ON
when the cargo lamp is
turned on and the ignition
key is turned to RUN.

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OnStar
System (If Equipped)
OnStar is a vehicle communications system that
offers a variety of services and provides a hands
-free
communication link between you and the OnStar Center.
A service subscription agreement and fee are required in
order to receive OnStar service. Services are available
24 hours a day, 7 days a week. For more information,
call 1
-888-ONSTAR-7 (1-888-667-8277).
OnStar Services Button: Press this button once
to contact an advisor who will be able to assist you with
these services. If you are not quickly connected, the
system will automatically reset and redial. This ensures
connection to the center; there is no additional action
required. Press the Call Answer/End button to cancel the
automatic redial.
Emergency Button: In an emergency situation,
press the emergency service button. Upon receiving the
call, an advisor at the center will locate your vehicle and
assess the situation. If necessary, the advisor will alert
the nearest emergency service provider.
Call ANSWER/END Button: Use this button
to answer a call. (If you are receiving a call, the audio
system will mute, and the ring will be heard). Press this
button at the end of a call to disconnect and return the
audio system to its previous settings. This button will
also cancel a call if one of the buttons is accidentally
pressed or if the automatic redial function is activated.
Volume Control: You can control the volume of the
OnStar System using either the volume knob on the
radio or using the steering wheel controls, if equipped.
Telltale Light: This light will indicate the status of
the system. A solid green light will come on when you
start the vehicle to let you know that the system is on
and is ready to make or receive calls.
If the light blinks green it means that an incoming
or outgoing call is in progress. Press the Call
ANSWER/END button if you notice the light
blinking and you are not on a call.

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The light will be red in the event of an OnStar system
malfunction. If this occurs press the OnStar button to
attempt to contact an advisor. If the connection is made,
the advisor will assist you with steps to take to make
sure that the system is functioning properly. If you
cannot contact the advisor, take your vehicle to your
dealership as soon as possible for assistance.
Safety and Security Services
Automatic Notification of Air Bag Deployment: If an
air bag deploys, a priority emergency signal is sent
automatically to the center. An advisor will locate your
vehicle's position, try to contact you and assist you in
the situation. If the center is unable to contact you,
an emergency service provider will be contacted.
Stolen Vehicle Tracking: Call the center at
1
-888-4-ONSTAR (1-888-466-7827) to report
your vehicle stolen. The system can then locate and
track your vehicle and the advisor will be able to notify
the proper authorities.
Roadside Assistance with Location: For vehicle
breakdowns, press the OnStar button. An advisor will
contact the appropriate help.Remote Diagnostics: If an instrument panel light
comes on, the center can perform a check of the engine
on
-board computer. An advisor can then recommend
what action needs to be taken.
OnStar MED
-NET: Med-Net can store your personal
medical history and provide it to emergency personnel
if necessary. (Requires activation and an additional fee.)
Accident Assist: An advisor can provide step
-by-step
guidance following an accident.
Remote Door Unlock: To contact the center, call
1
-888-4-ONSTAR. You will be required to provide
your security information. An advisor will send a
command to your vehicle to unlock itself. The advisor
can delay unlocking your vehicle. Remote Door Unlock
is disabled 48 hours after the vehicle is parked to
maintain the battery charge.
Vehicle Locator Service: To contact the center,
call 1
-888-4-ONSTAR. You will be required to
provide your security information. An advisor will send
a command to your vehicle to sound the horn and/or
flash the lamps.
In order to provide you with excellent service, calls with
the OnStar Center may be monitored or recorded.

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Premium Services (Includes Safety and
Security Services)
Route Support: An advisor can provide directions
or guidance to anywhere you want to go. In addition,
they can help you locate gas stations, rest areas, ATMs,
hospitals, stores, eateries and more.
Concierge Services: The concierge advisor can obtain
tickets, reservations or help with vacation/trip planning
and other unique items and services.
Ride Assist: An advisor can locate transportation in the
event that you are unable to drive.
OnStar System Limitations
Complete limitations can be found on the subscriber
services agreement.
OnStar Service is:

available in the 48 contiguous United States, Alaska,
Hawaii and Canada;

available when the vehicle is within the operating
range of a cellular provider;
subject to limitations caused by atmospheric
conditions, such as severe weather or topographical
conditions, such as mountainous terrain.

subject to cellular carrier equipment limitations.
Global positioning capabilities used to deliver
OnStar service will not be available if satellite
signals are obstructed.
OnStar will not function if the vehicle's battery
is discharged or disconnected. It may also be
inoperative if the vehicle is in an accident and the
OnStar or vehicle electrical system components
are damaged.
Safety and security services are provided by existing
governmental emergency service providers. OnStar
will use reasonable efforts to contact the appropriate
emergency service provider and request assistance but
cannot promise that they will respond to the call in a
timely manner or at all.

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HomeLink
Transmitter
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,
and (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, and (2) this
device must accept any interference, including
interference that may cause undesired operation of
the device.
Changes and modifications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Programming the HomeLink Transmitter
Do not use the HomeLink Transmitter 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.
Be sure that people and objects are clear of the garage
door you are programming.
It is recommended that a new battery be installed in
your hand
-held transmitter for quicker and more
accurate transmission of the radio frequency.
Your vehicle's engine should be turned off while
programming the transmitter. Follow these steps to
program up to three channels:
1. Decide which one of the three channels (one of the
HomeLink buttons) you want to program.
2. Press and hold the desired button on HomeLink
through Step 3.

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If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air bag
system may not work properly. Have your vehicle
serviced right away.
CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to RUN. 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
United States Canada
When your engine is not running, but the ignition is in
RUN, 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.

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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
flash when you set the parking brake. The light will flash
if the parking brake doesn't release fully. If you try to
drive with the parking brake engaged, a chime will sound
when the vehicle speed is greater than 3 mph (5 km/h).
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.
United States Canada