Factory reset Ademco Vista 20p | LiveWatch Security®.
(1)Power the system down by disconnecting battery and pulling out the power transformer.
(2)Plug the transformer back in and immediately press * and # simultaneously. Hold them until you see a “20” displayed.
(3) enter #20 and the display will read out your existing installer code, scrolling it out in two-digit numbers: For example, if the code is 1-2-3-4, it will scroll 01-02-03-04. That gives you the code to get into programming again without having to power down and back up.
(4) To change the installer code, press * and the 4-digit code you want (Ex. 1-2-3-4), and * again.
(4) Return the programming to factory defaults by entering *97
(5)Leave programming by entering *99
WARNING: If you leave programming by entering *98, you cannot get back into programming with the Installer Code. Use only *99 to exit programming.
(6) Read the Installation Manual thoroughly.
Power the system down (battery then AC power); Restore AC power. Within 50 seconds press * + # at the same time on any keypad.
If nothing odd was done in the system setup, you will be in program mode.
Press #20. The digits that the system reads back are the installer code; write them down.
Exit programming with *99.
Changing the System Master code…
Using Installer code: Installer code + [8] + 02 + new code
(somewhere along the line, reconnect the battery. You may need to go into program mode again to disable the dialer if the system was previously monitored)