My 84's light flashed intermittently for years and it had nothing to do
with the cooling system.  It was a short somewhere in the dash area.
Sometimes a good whack on the cover of the instrument panel would cure
it.  I  shouldn't have, but I got to where I ignored it after checking
the coolant so many times only to find no problem.

When I got the 85 weekender, it didn't do this, but after I replaced the
instrument panel in order to pass inspection,  (It had broken mounting
tabs and couldn't be firmly fixed in place.) I started getting this
intermittent flicker even though everything checked out visually in the
cooling system.  Either from the archives or some email with list
members, I got the information that this could also be caused by lack of
a good electrical contact between the panel connector and the wires from
under the dash.  It took several repeat disassemblies and reconnections
to get it right, but it hasn't flashed in about 6k miles after acting
just like the 84 did for quite a while.  So, it could be that the
flashing has nothing to do with your cooling system.

Check both though.

Sam

--
Sam Walters
Baltimore, MD

89 Syncro GL
85 Westy Weekender
84 Vanagon, original owner, soon to be retired, just too many problems

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