I had this happen on my '87.  Not sure if it's the same on the '85, but
with mine my system had some air in it.  The symptom was that the LED
would periodically start blinking but the temp gauge did not go up.
When I'd turn the van off, the blinking would stop for a few minutes
then go back on.  I found that the coolant level in the expansion tank
was low, but being inexperienced with Vanagons, I was, at first,
loosening the cap on the expansion tank a little bit.  The tank would
fill up quickly from the pressure in the system and the light would go
out.  BUT, the light would eventually come back on.  The way I fixed it
was to wait until the van was cold and put coolant into the fill tank
until it was up to the Max line.  I did this every day over the course
of the week and by the end of the week, the level had stabilized and the
LED hasn't come on since.  This was about three years ago.

Good luck,
Marc Perdue

Damon Campbell wrote:

> As always, check grounds.  I would think that if the
> sensor went bad giving a false reading of no coolant,
> the needle would jump up as well.  Just a blinking LED
> would make me suspect a circuit independent of the
> sensor...  Especially if it has been intermittant.
>
> But definitely check the coolant level, anyway.
>
> -Damon
>
> --- Richard Brassaw <sendmeanemail@EARTHLINK.NET>
> wrote:
> > One of two things usually cause the blinking
> > light--other than your
> > engine overheating.  Either the sensor has gone bad
> > or there isn't
> > enough coolant in the system.
>
> =====
> '84 Westy (Sparky)
> '65 Kharma Ghia (Dharma)
>
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