I have an old Scantronic 9100 house alarm with a reset problem having opened the front panel to inspect the battery (I have the engineer's code). After doing so, the expected command (i.e. zero enter/engineer's code/99 enter) to restore "day mode" does not work. Only the "power" LED is showing. Does this mean a full reset involving the NVM chip as advised elsewhere on this Forum is the only solution? Any ideas avoiding this would be much appreciated.

Romo1947, July 2020

Thanks for this. I am not sure that I quite follow your suggestion. However, I have tried “99“ Followed by enter but this does not restore “Day” mode.

Romo1947, July 2020

ok, is it possible that the system has reverted to default codes, not unknown on these older panels? On leaving engineer mode simply press 99 then enter. No need to use the code at that point.

I would try setting with default code before attempting to restore by removing nvm chip, usually quite fragile.

Alan, July 2020

Thanks. I used the Engineer’s code for my system and the ‘day’ light went out confirming that the alarm was in Engineer‘s mode.

Romo1947, July 2020

when you opened the cover what code did to use to stop the internal sounder? If you used your customer code, then you did not enter the engineer mode, hence the reset you are trying to do will not work. You would have to be in engineer mode for the sequence you describe to have any affect.

Alan, July 2020