After 3years, my ceiling fan now turns itself own in low and its lights come on as well. I have had the remote reprogramed and replaced the switch assembly, but the problem still exists. It's a mystery to me, help.

Are there any other RF sources in your home like remote TV or Dish? Changing the code should have eliminated this issue but I think it is still a likely source of the "ghost".

Have you changed the frequency in both the remote and receiver?

Ceiling fan remote controls - help and FAQ- Ceiling Fans N More