David, my '84 behaves as you describe except when the engine is cold.  I had
some occasions in the past (before I figured out what was going on) when
coolant level was below the sensor when the engine was cold.  Red light
would flash, but temperature gauge would read accurately.  Those events
probably occurred before I bought one of the update instrument clusters that
the list vendors were selling in 1999.

John Lauterbach
Macon, GA
'84 DL

----- Original Message -----
From: "David Beierl" <dbeierl@ATTGLOBAL.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Thursday, January 11, 2001 2:35 PM
Subject: Help! Appeal for data

> Volks, I've got some conflicting data concerning the low-coolant warning
> and could use help sorting it out.  Briefly (briefly? me?) the Bentley
> wiring diagram for all years indicates that there are only three terminals
> on the temp gauge/blinker assy -- +10v, ground, and sender; and that the
> low-coolant circuit operates by grounding the sender lead, thus simulating
> an overtemp condition (so the gauge goes offscale and the light
> blinks).  This is how my '85 and '85 behave.
>
> HOWEVER, I've gotten reports in the past that some V'gons only blink the
> light under these conditions and the gauge does not rise.
>
> I'd very much appreciate it if a whole bunch of you would go out, turn on
> your ignition and wait until the light stops blinking, then unplug the
> low-coolant sensor and tell me what happens.  What I expect to happen is
> that the light instantly starts blinking, then the needle rises and goes
> offscale over say ten seconds or so.  When you plug the sender back in the
> gauge soon starts to fall; the light blinks for another ten seconds or so
> and shuts off.
>
> Please let me know the year of your V'gon and how your results compare
with
> what I've just described.
>
> thanks
> david
>
>
> David Beierl - Providence, RI
>   http://pws.prserv.net/synergy/Vanagon/
> '84 Westy "Dutiful Passage"
> '85 GL "Poor Relation"