הוראות כיצד להחליף בטריה בשעון זיהוי פנים FA2:
If you use the FA2 more than years, I think maybe the clock battery is dying, the clock battery is use for keeping the time, you can try to replace the clock battery if the voltage less than 2V, and then test again.
The clock battery model is CR1220, DC 3V, the below photo is main board of new firmware FA2

(נצפה סה"כ 10 פעמים. נצפה היום 1 פעמים)

