2008 CHEVROLET SILVERADO 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 a door with the RKE transmitter.
Unlocking a door any other way will set off the alarm
if the system has been 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 it off.
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
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.
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,
seeFuses and Circuit Breakers on page 5-125.
If the alarm does not sound or the headlamps do not
ash, see your dealer/retailer for service.
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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 5-125. 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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When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the message PARKING ASSIST OFF will be
displayed on the DIC and a red light will be shown on the
rear URPA display when the shift lever is moved into
R (Reverse). This occurs under the following conditions:
The driver disables the system.
The parking brake pedal is depressed.
The ultrasonic sensors are not clean. Keep the
vehicle’s rear bumper free of mud, dirt, snow, ice and
slush. For cleaning instructions, seeWashing Your
Vehicle on page 5-118.
A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the tailgate during the
last drive cycle, the red light may illuminate in the
rear display. Once the attached object is removed,
URPA will return to normal operation.
A tow bar is attached to the vehicle.
The vehicle’s bumper is damaged. Take the vehicle
to your dealer/retailer to repair the system.
Other conditions may affect system performance,
such as vibrations from a jackhammer or the
compression of air brakes on a very large truck.
If the system is still disabled, after driving forward at
least 15 mph (25 km/h), take the vehicle to your
dealer/retailer.
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.
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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.
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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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Center Console Storage
Your vehicle may have an upper and lower center
console storage area with cupholders.
To access the upper storage area, pull lever (A) up.
To access the lower storage area, raise the upper
storage bin, then pull lever (B) up. Use the key to
lock and unlock the lower storage area.
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.
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