found this...don't know if it applies to your alarm, but it might work:

"Put the key in the ignition, and turn forward
all the way just before cranking. Then within
5 seconds, press and hold in the valet/overide
button, found under the dash area,
until the installed LED (the blinking light)
in your dash area goes off, and the siren chirps twice.
(Your valet switch might be the toggle (on/off) type.
in this case, key on, flip switch in oposite direction,
key off.)

This should reset the alarm."

goodluck