Lathem Sonachron Battery
Standard lifespan is about 3 years.
Is the time difficult to read on the display?
The battery is dying.
Lost the program altogether?
You might have gotten a power surge, or the battery is dead.
First thing you do is replace the battery.
Leave it plugged in. Remove the left side panel.
Replace the battery and test the signal.
Do you have power at the plug? Plug in a lamp to test the outlet.
If it still does not work, then you will need to reset the program.
In any event, the battery needed replacing.