'87 5ktq coolant/temp warning indicator

[Ben Swann]

5000 cs turbo quattro avant coolant/temp warning indicator

It is on/flashing.  Figuring it was low coolant level, I added coolant.  It
was low, but not that low.  Now coolant is up to level, and the indicator
is still flashing.  Does this switch indicate too much coolant also?  What
else triggers the indicator?

The engine is not overheating,  temp is normal - mid guage.

I did some work the other day and had to remove the intake manifold,
installed cam, etc.  Engine runs great. Just that is when I noticed the
indicator.  Is there another switch/sensor I ought to check?

TIA for suggestions

Ben