2008 CHEVROLET AVALANCHE ECU

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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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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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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2. Locate in the garage, the garage door opener
receiver (motor-head unit). Locate the “Learn”
or “Smart” button. It can usually be found where the
hanging antenna wire is attached to the motor-head
unit and may be a colored button. Press this
button. After pressing this button, complete the
following steps in less than 30 seconds.3. Immediately return to the vehicle. Press and hold
the Universal Home Remote button that will be
used to control the garage door until the garage
door moves. The indicator light, above the selected
button, should slowly blink. This button may
need to be held for up to 20 seconds.
4. Immediately, within one second, release the button
when the garage door moves. The indicator light
will blink rapidly until programming is complete.
5. Press and release the same button again.
The garage door should move, conrming
that programming is successful and complete.
To program another Rolling Code device such as
an additional garage door opener, a security device,
or home automation device, repeat Steps 1 through 5,
choosing a different function button in Step 3 than
what was used for the garage door opener.
If these instructions do not work, the garage door
opener is probably a Fixed Code unit. Follow the
Programming instructions that follow for a Fixed Code
garage door opener.
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5. After entering all of the switch positions, again,
rmly press and release all three buttons at the
same time. The indicator lights will turn on.
6. Press and hold the button that will be used to
control the garage door until the garage door
moves. The indicator light above the selected button
should slowly blink. This button may need to be
held for up to 55 seconds.
7. Immediately release the button when the garage
door moves. The indicator light will blink rapidly
until programming is complete.
8. Press and release the same button again.
The garage door should move, conrming
that programming is successful and complete.
To program another Fixed Code device such as an
additional garage door opener, a security device,
or home automation device, repeat Steps 1-8, choosing
a different button in Step 6 than what was used for
the garage door opener.
Using Universal Home Remote
Press and hold the appropriate button for at least
half of a second. The indicator light will come on
while the signal is being transmitted.
Reprogramming Universal Home
Remote Buttons
Any of the three buttons can be reprogrammed by
repeating the instructions.
Erasing Universal Home Remote
Buttons
The programmed buttons should be erased when the
vehicle is sold or the lease ends.
To erase either Rolling Code or Fixed Code on the
Universal Home Remote device:
1. Press and hold the two outside buttons at the
same time for approximately 20 seconds, until
the indicator lights, located directly above the
buttons, begin to blink rapidly.
2. Once the indicator lights begin to blink, release both
buttons. The codes from all buttons will be erased.
For help or information on the Universal Home Remote
System, call the customer assistance phone number
underCustomer Assistance Offices on page 7-5.
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Luggage Carrier
The vehicle may have a luggage carrier that can be
used to load things on top of the vehicle.
The luggage carrier has siderails attached to the roof.
It may also have crossrails which can be moved
back and forth to help secure cargo. Tie the load
to the siderails or siderail supports.
Notice:Loading cargo on the luggage carrier that
weighs more than 200 lbs (91 kg) or hangs over
the rear or sides of the vehicle may damage your
vehicle. Load cargo so that it rests on the slats
as far forward as possible and against the side rails,
making sure to fasten it securely.
Do not exceed the maximum vehicle capacity when
loading your vehicle. For more information on vehicle
capacity and loading, seeLoading Your Vehicle on
page 4-36.
To prevent damage or loss of cargo while you are
driving, check to make sure the luggage and cargo are
still securely fastened.Be sure the cargo is properly loaded.If small heavy objects are placed on the roof, cut a
piece of 3/8 inch plywood to t inside the crossrails
and siderails to spread the load. Tie the plywood
to the siderail supports.
Tie the load to the crossrails or the siderail
supports. Use the crossrails only to keep the load
from sliding. To move a crossrail, lift the release
lever, on both sides of the rail, up to loosen it. Slide
the crossrail to the desired position balancing the
force side to side. Press the release lever on both
sides of the rail, down to tighten it. Try to slide the
crossrail back and forth slightly to be sure it is tight.
If you need to carry long items, move the crossrails
as far apart as they will go. Tie the load to the
crossrails and the siderails or siderail supports. Also
tie the load to the bumpers. Do not tie the load so
tightly that the crossrails or siderails are damaged.
After moving a crossrail, be sure it is securely locked
into the siderail.
Your vehicle has a Center High-Mounted Stoplamp
(CHMSL) located above the rear glass.
If items are loaded on the roof of the vehicle, care
should be taken not to block or damage the CHMSL unit.
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