If you mean the little ones, that replace a light switch .... count your blessings it still works!
I've used every variety of them - Intermatic has two basic types - and all have gone bad after very brief periods. The current model is still switching automatically, but you cannot operate the switch manually, or change the program.
I'd just buy another one of these $35 gizmos, then hold on to the guts. You're soon to need them!
