My guess is that it's a specific error code, some kind of a subroutine built into this fixture to signal a short circuit, although I haven't tried to research it yet. There's nothing like four inches of rain to really p*ss off the fire ants, and immediately after this started happening, I discovered that they had invaded the exterior wall right below this light. Furthermore, we noticed that have been unable to reset a GFCI that ties into this wall (different circuit, same location). I've never seen fire ants trash a motion light before, but with ants, there's a first time for everything.
In case you need some background on this undesirable phenomenon, TAMU has a publication called "It's shocking what fire ants can do to electrical equipment". Looks like my husband has his honey-do all laid out for his Sunday afternoon. Bzzzzt.