Chevrolet 2003 Impala Owner's Manual page 109

Be sure that people and objects are clear of the garage
door or gate operator you are programming. When
programming a garage door, it is advised to park outside
of the garage.
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:
2
Press and hold down the two outside buttons,
releasing only when the indicator light begins to
flash, after 20 seconds. Do not hold down the
buttons for longer than 30 seconds and do not
repeat this step to program a second and/or third
transmitter to the remaining two HomeLink@ buttons.
Position the end of your hand-held transmitter about
1 to 3 inches (3 to 8 cm) away from the HomeLink@
buttons while keeping the indicator light in view.
3 .
Simultaneously press and hold both the desired
button on HomeLink@ and the hand-held transmitter
button. Do not release the buttons until Step 4
has been completed.
Some entry gates and garage door openers may
require you to substitute Step 3 with the procedure
noted in "Gate Operator and Canadian
Programming'' later in this section.
4. The indicator light will flash slowly at first and then
rapidly after HomeLink@ successfully receives the
frequency signal from the hand-held transmitter.
Release both buttons.
5. Press and hold the newly-trained HomeLink@ button
and observe the indicator light.
If the indicator light stays on constantly,
programming is complete and your device should
activate when the HomeLink@ button is pressed and
released.
To program the remaining two HomeLink@ buttons,
begin with Step 2 under "Programming HomeLink@."
Do not repeat Step 1 as this will erase all of the
programmed channels.
If the indicator light blinks rapidly for two seconds
and then turns to a constant light, continue with
Steps 6 through 8 following to complete the
programming of a rolling-code equipped device
(most commonly, a garage door opener).
6. At the garage door opener receiver (motor-head
unit) in the garage, locate the "Learn" or "Smart"
button. This can usually be found where the hanging
antenna wire is attached to the motor-head unit.
7. Firmly press and release the "Learn" or "Smart"
button. The name and color of the button may
vary by manufacturer.
You will have 30 seconds to start Step 8.
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