Quick Reference; Valet Switch - Audiovox Prestige APS99BT3 Owner's Manual

(b) Press and hold any combination of two buttons simultaneously, until
the siren emits a long chirp tone. This confirms that programming of
channel 4 was successful. Up to 4 transmitters can be programmed,
press and hold the selected button of each additional transmitter until
the chirp tone is heard, or press and release the push button switch to
exit the programming mode, or turn the ignition switch off to exit the
programming mode.
The siren emits a long followed by a short chirp tone indicating that the program
mode has been exited.
NOTE: If programming to a Keyless Entry (non alarm) unit, there will be NO
chirp indication.

QUICK REFERENCE:

You can program any individual channel, without reprogramming all channels,
by following the quick reference chart below. (Not All Units Have 4 Channels)
CHANNEL

VALET SWITCH

Press and Release 3 Times
1
Press and Release 4 Times
2
Press and Release 5 Times
3
Press and Release 6 Times
4
After the desired channel is programmed, turn the ignition key to the off position
to exit programming mode.
LED
1 Flash
2 Flashes
3 Flashes
4 Flashes