Hi,
A few years back I did a DIY install of an Ademco 50P.
In the process of adding new devices this morning I got lost in the programing menu and cound not back out, so I powered down the panel (disconnected the power and batteries for about 30 seconds) then powered it back up.
The panel came back up as ready to arm, but would no longer accept the instaler code to enter the programming mode, arm the system, or anything else - I can arm and disarm the system via a user code, it reports fault conditions and all the changes I made prior to the power-down seem to be in effect, it just does not respond in any way I can discover to the instaler code.
Any suggestions?