Security & Fire Protection Systems/Battery replaced on Security System


We have a First Alert FA120C Security System
We replaced the back-up battery and now it constantly scrolls through each zone saying "Not ready".
It seems like the whole system needs a master code or something to reset it. But our security code is not being effective.
Thank you.

Do you have any wireless transmitters in your system?  The "low battery" signal could have been from these (which would also explain the "not ready" indication at the keypad).  Replacing the main system battery shouldn't have any effect on your system (as programmed information is lodged in EEPROM memory and retained until your installer changes it).

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Frank Kurz


Questions relating to Burglar Alarm and Security Equipment, Fire Alarm and Extinguishment Systems, Access Control, CCTV Systems, Installation, Service, Testing, Verification


30 years installing, servicing, and testing security, access control, extinguishment, and fire alarm systems

Chair of ULC Working Groups for Fire Alarm Testing (CAN/ULC-S536) and Fire Alarm Verification (CAN/ULC-S537), Executive Director of the Fire Protection Technicians Network (

Publications, Better Business Bureau Magazine, Applied Science Technologists and Technicians of British Columbia ( SUPPRESS! and Techs Fire Break Newsletters

Associate in Science; Emergency Systems (University of British Columbia); Aircraft Maintenance Technology (BCIT)

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