I recently fired up my engine after it sat with the cooling system open for
several months, 'cause I was uninspired to finish an H2O pump replacement.
I got it running on Saturday and the silly light flashed at me all day, even
though it had plenty of coolant and wasn't running hot.  Then I fired it up
again yesterday for a run to the dump in Lacey, and it just flashed upon
initial start up and never again.  I don't have a clue why it decided to
play nice.  Perhaps because it found religion on Sunday.

--
Casey