2008 CHEVROLET AVALANCHE service

The theft-deterrent system will not activate if the doors
are locked with the vehicle’s key or the manual door lock.
It activates only if you use the power door lock switch with
the door open or the RKE transmitter. You should also
remember that you can start your vehicle with the correct
ignition key if the alarm has been set off.
To avoid setting off the alarm by accident:
If you do not want to activate the theft-deterrent
system, the vehicle should be locked with the
door key after the doors are closed.
Always unlock the doors with the RKE transmitter.
Unlocking a door any other way will set off the
alarm if it is armed.
If you set off the alarm by accident, press unlock on
the RKE transmitter or place the key in the ignition and
turn it to START to turn off the alarm. The alarm will
not stop if you try to unlock a door any other way.
Testing the Alarm
To test the alarm:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the RKE transmitter.
3. Get out of the vehicle, close the door and wait for
the security light to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door.
This should set off the alarm.
While the alarm is set, the power door unlock switch will
not work.
If the alarm does not sound when it should but the
headlamps ash, check to see if the horn works.
The horn fuse may be blown. To replace the fuse,
seeInstrument Panel Fuse Block on page 5-109
andUnderhood Fuse Block on page 5-111.
If the alarm does not sound or the headlamps do
not ash, the vehicle should be serviced by your
dealer/retailer.
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PASS-Key®III+ Electronic
Immobilizer
The PASS-Key III+ system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
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.
PASS-Key III+ uses a radio frequency transponder in
the key that matches a decoder in the vehicle.
PASS-Key®III+ Electronic
Immobilizer Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent system.
PASS-Key
®III+ is a passive theft-deterrent system.
The system is automatically armed when the key
is removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN, ACC/ACCESSORY or START
from the LOCK/OFF position.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problem
with arming or disarming the theft-deterrent system.
When the PASS-Key
®III+ system senses that someone
is using the wrong key, it prevents the vehicle from
starting. Anyone using a trial-and-error method to start
the vehicle will be discouraged because of the high
number of electrical key codes.
If the engine does not start and the security light on
the instrument panel cluster comes on when trying to
start the vehicle, there may be a problem with your
theft-deterrent system. Turn the ignition off and try again.
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If the engine still does not start, and the key appears to
be undamaged, try another ignition key. At this time,
you may also want to check the fuse, seeFuses
and Circuit Breakers on page 5-108. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the rst key may be
faulty. See your dealer/retailer who can service the
PASS-Key
®III+ to have a new key made. In an
emergency, contact Roadside Assistance.
It is possible for the PASS-Key
®III+ decoder to learn
the transponder value of a new or replacement key.
Up to 10 keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only. If all the currently programmed keys are
lost or do not operate, you must see your dealer/retailer
or a locksmith who can service PASS-Key
®III+ to
have keys made and programmed to the system.
See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.To program the new additional key:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key in the
ignition and start the engine. If the engine will not
start, see your dealer/retailer for service.
3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the new key to be programmed and turn it to
the ON/RUN position within ve seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has been
programmed.
5. Repeat Steps 1 through 4 if additional keys are to
be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the rst 500 miles (805 km).
Do not drive at any one constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting to
brake or slow the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time the new brake
linings are not yet broken in. Hard stops with
new linings can mean premature wear and earlier
replacement. Follow this breaking-in guideline
every time you get new brake linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-47for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
Ignition Positions
Use the key to turn the
ignition switch to four
different positions.
In order to shift out of PARK (P), ignition must be in the
ON/RUN or ACC/ACCESSORY and the regular brake
pedal must be applied.
A (LOCK/OFF):This position locks the ignition and
transmission. It is a theft-deterrent feature. The key
can only be removed when the ignition is turned to
LOCK/OFF.
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the key.
Use the correct key and turn the key only with your
hand. Make sure the key is all the way in. If it is, turn
the steering wheel left and right while you turn the
key hard. If none of this works, then your vehicle
needs service.
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You can choose among ve driving settings:
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briey when
you turn on the ignition and the last chosen setting will
stay on. If the lights do not come on, you should take your
vehicle in for service. An indicator light will ash while
shifting. Fast ashing means the conditions were not met
to make the desired shift, typically the vehicle was going
too fast, the automatic transmission was not in neutral.
Slow ashing means the shift is in progress. It will stay
on when the shift is completed. If for some reason the
transfer case cannot make a requested shift, it will return
to the last chosen setting.
2
m(Two-Wheel Drive High):This setting is used
for driving in most street and highway situations.
Your front axle is not engaged in two-wheel drive.
This setting also provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive):This setting is
ideal for use when road surface traction conditions are
variable. When driving your vehicle in AUTO, the front
axle is engaged, but the vehicle’s power is primarily
sent to the rear wheels. When the vehicle’s software
determines a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy than
Two-Wheel Drive High.4
m(Four-Wheel Drive High):Use the four-wheel
high position 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.
4
n(Four-Wheel Drive Low):This setting also
engages your front axle and delivers extra torque.
You may never need this setting. It sends maximum
power to all four wheels. You might choose Four-Wheel
Drive Low if you are driving off-road in deep sand,
deep mud, deep snow, and while climbing or descending
steep hills. StabiliTrak
®will not engage in this mode.
SeeStabiliTrak®System on page 4-6for more
information.
{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. SeeParking Brake on
page 2-44.
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NEUTRAL (N):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-42orTowing
Your Vehicle on page 4-42for more information.
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take your vehicle to your dealer for service.
See “SERVICE 4 WHEEL DRIVE message” under
DIC Warnings and Messages on page 3-59.
Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO position.
This can be done at any speed, except when shifting
from Four-Wheel Drive Low. The indicator light will
ash while shifting. It will remain on when the shift is
completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position. This can
be done at any speed, except when shifting from
Four-Wheel Drive Low.
See shifting out of Four-Wheel Drive Low later in this
section for more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel Low is engaged, vehicle speed
should be kept below 45 mph. Extended high-speed
operation in 4L may damage or shorten the life of
the drivetrain.
To shift to the Four-Wheel Drive Low position, the
ignition must be in ON/RUN and the vehicle must be
stopped or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred method for
shifting into Four-Wheel Drive Low is to have your vehicle
moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the knob to the
Four-Wheel Drive Low position. You must wait for the
Four-Wheel Drive Low indicator light to stop ashing and
remain on before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
Four-Wheel Drive Low indicator light to stop ashing
before shifting the transmission into gear.
The vehicle may have signicant engagement noise and
bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from NEUTRAL
while the engine is running.
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Shifting Out of Park
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
Prevent ignition key removal unless the shift
lever is in PARK (P) with the shift lever button fully
released, and
Prevent movement of the shift lever out of
PARK (P), unless the ignition is in ON/RUN or
ACC/ACCESSORY and the regular brake pedal is
applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than 9 volt)
battery.
If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. SeeJump Starting on page 5-42for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.If you still are unable to shift out of PARK (P):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into PARK (P).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have your
vehicle serviced soon.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass, or other
things that can burn.
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{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. Do not leave your vehicle when the engine
is running unless you have to. If you have left
the engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle will not move, even
when you are on fairly level ground, always
set the parking brake and move the shift lever
to PARK (P).
{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to roll,
even if the shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL. Always set the parking brake.Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into Park on page 2-45.
If you are pulling a trailer, seeTowing a Trailer on
page 4-47.
Mirrors
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.
Control buttons for the OnStar
®system, if equipped, are
at the bottom of the mirror. SeeOnStar®System on
page 2-61for more information about the services
OnStar
®provides.
P(On/Off):This is the on/off button.
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