Danny D'Amico wrote:

Dead alarm system troubleshooting advice requested ...

I wondered why the backup battery didn't run the alarm system.
Testing the 12V 5AH battery out of the alarm system shows it's 13.5
volts DC (no load open circuit voltage), which, at least seems OK
(I don't know how to load it though):
http://farm4.staticflickr.com/3731/1...d9f59f77_o.gif

If the alarm battery is more than 4 or 5 years old, there's a good chance it
won't support any kind of load. They are cheap - I'd replace it.