2004 CHEVROLET AVALANCHE ECU

The following are the main components of the midgate
system:
A. Latch Levers
B. Grab Handles
C. Glass-Catch
Release Button
D. Glass Lock KnobsE. Window
Retaining Tabs
F. Midgate Release
Handle
G. Window Alignment
ArrowsRear Glass Removal and Storage
{CAUTION:
If the removable rear glass is not stored
properly, it could be thrown about the vehicle
in a crash or sudden maneuver. People in the
vehicle could be injured. Whenever you store
the rear glass in the vehicle, always be sure
that it is stored securely in the midgate
storage pocket.
Do not remove the rear glass when the rear defroster is
on. If you remove the rear glass with the rear defroster
on, you may see a discharge spark coming from
the latch area.
To remove the rear glass do the following:
1. Fold the rear seats. SeeRear Seat Operation on
page 1-7for more information. The front seats
may have to be moved forward slightly to allow the
rear seats to fold completely.
Although the rear glass can be removed without
folding the rear seats, you will not be able to access
the rear glass storage pocket. Be sure to fold the
seatsbeforeremoving the rear glass.
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6. Turn both glass lock knobs (D), located at both top
corners of the storage pocket, to the locked
position. Push in on the corner of the rear glass to
allow the lock knob to engage more easily.Once both glass lock knobs are in the locked
position, the rear glass is securely stored.
7. Push both latch levers up to the locked position.
You should hear a click when each latch lever
locks correctly.
The rear seats can be returned to the normal
position when the rear glass is out and stored
properly in the storage pocket.
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Lowering the Midgate with the Rear Glass
in Place
The midgate can be lowered to allow the cargo area of
your vehicle to extend into the cab. The rear glass
can be either installed in its normal position, or it can be
removed and stored in the rear glass storage pocket.
To lower the midgate, do the following:
1. Fold the rear seats. The front seats might have to
be moved forward slightly to allow the rear seats to
fold. SeeRear Seat Operation on page 1-7for
more information.
2. Standing outside of the vehicle, hold the midgate
securely so it does not fall forward. Turn the
midgate handle clockwise and pull the midgate
toward you.Rear Glass in Normal Position
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This procedure works the same as the procedure
described previously (with the rear glass installed), but
when you lower the midgate with the rear glass in
the stored position, you will notice that the entire
crossbar (the bar with the release handle) will lower with
the midgate. This is completely normal; however,
since the crossbar lowers with the midgate, it will be
heavier. As you lower the midgate in this conguration
be ready for the extra weight and be careful not to
let the midgate fall as you lower it.
Raising the Midgate
To return the midgate to its normal position, raise the
midgate up with a rm swinging motion (this will help to
ensure that the midgate closes with enough force to
engage the latches) until it latches into place securely.
If the rear glass is removed and you would like to
put it back, do so using the instructions given previously.
Tailgate
Use the ignition/door key to unlock/lock the tailgate.
Open the tailgate by lifting up on its handle while pulling
the tailgate toward you.
To shut the tailgate, rmly push it upward until it
latches. Push and pull on the tailgate to be sure it is
latched securely. Midgate Lowered with Crossbar Attached
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Tailgate Removal
The tailgate can be removed to allow for different
loading situations. Although the tailgate can be removed
without assistance, you may want someone to assist
you with the removal to avoid possible damage to
the vehicle.
To remove the tailgate, do the following:
1. Hold the tailgate up, slightly raised.
2. Release the retaining
cable clip by lifting the
cable so it is level
with the ground and
then push the cable clip
toward the vehicle.
3. Raise the tailgate at a slight upward angle, pull back
on the tailgate at the right edge so it releases from
the block hinge (arrow) and then move the tailgate to
the right to release the left edge.
Reverse the above procedure to reinstall. Make sure the
tailgate is secure.
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Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
Although your vehicle has a number of theft-deterrent
features, we know that nothing we put on it can make it
impossible to steal.
Content Theft-Deterrent
Your vehicle is equipped with a content theft-deterrent
alarm system.
With this system, the
security light in the
instrument panel cluster will
ash as you open the door
if your ignition is off.
This light reminds you to activate the theft-deterrent
system. Here’s how to do it:
1. Open the door.
2. Lock the door with the power door lock switch or
the remote keyless entry transmitter. The security
light should come on and stay on.3. Close all doors. The security light should go off
after about 30 seconds. The alarm is not armed
until the security light goes off.
If a locked door is opened without the key or the remote
keyless entry transmitter, the alarm will go off. The
headlamps and parking lamps will ash for two minutes,
and the horn will sound for 30 seconds, then will turn
off to save the battery power. You can choose different
feedback options for the alarm. SeeDriver Information
Center (DIC) on page 3-53.
Remember, the theft-deterrent system won’t activate if
you lock the doors with a key or use the manual
door lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that
you can start your vehicle with the correct ignition key if
the alarm has been set off.
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Here’s how to avoid setting off the alarm by accident:
If you don’t want to activate the theft-deterrent
system, the vehicle should be locked with the door
keyafterthe doors are closed.
Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any
other way will set off the alarm.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
unlock on the remote keyless entry transmitter. The
alarm won’t stop if you try to unlock a door any other
way.
Testing the Alarm
The alarm can be tested by following these steps:
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 remote keyless entry 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 is
not operational.
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 5-120.
If the alarm does not sound or the headlamps do not
ash, the vehicle should be serviced by your dealer.
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Passlock®
Your vehicle is equipped with the Passlock®
theft-deterrent system.
Passlock
®is a passive theft-deterrent system. Passlock®
enables fuel if the ignition lock cylinder is turned with
a valid key. If a correct key is not used or the ignition
lock cylinder is tampered with, the fuel system is
disabled and the vehicle will not start.
During normal operation, the security light will turn off
approximately ve seconds after the key is turned
to RUN.
If the engine stalls and the security light ashes, wait
about 10 minutes until the light stops ashing before
trying to restart the engine. Remember to release
the key from START as soon as the engine starts.If the engine does not start after three tries, the vehicle
needs service.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®at this
time. You may also want to check the fuse. See
Fuses and Circuit Breakers on page 5-120. See your
dealer for service.
In an emergency, call the Roadside Assistance Center.
SeeRoadside Assistance Program on page 7-6.
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