Without more details I am limited in my response.Does your temp needle
peg?
When I ground the wire on my wifes' 85 GL temp gauge sending unit the
light flashes and the needle pegs. this jibes with the circuit
schematic. the sender is inversely proportional to temp i.e. as temp
increases resistance decreases. 

as for shorting the level sensor,beeeeep, sorry ,try again. that is what
the circuit is looking for to be "happy". Again, I just unplugged the
level sender and turned on the ignition,two things happened...1>light
flashed(normal)and went out b>five second later it came back on
(flashing) and needle started climbing.

 the above test on 85 digijet system

[I jotted down in my manual that the needle touches the first mark when
the sender equals 340 ohms . the last mark is reached with sender = 30
ohms.
this data from 86 digifant system
good luck
ken

On Thu, 18 Jul 1996 07:21:24 -0500 niel.blackwell@srs.gov writes:
>Sometimes these things must sense we have the upper hand and then do 
>things to 
>remind us we are mere mortals... Last night added new voltage 
>stabilizer... 
>light still flashes. Shorted connector at bottle, no change. Tightened 
>ground 
>connections at engine, nothing. Bentley shows a coolant light 
>controller or 
>relay in wiring diagram... anyone seen this or a had problem with it. 
>I looked 
>on fuse panel with other relays and didn't see it. This is a matter of 
>honor 
>now. I will not degrade myself and go to a dealer. Thanks for the 
>responses so 
>far. I hate that light...
>