this is a bit of a warning for the archives.  i just finished changing out
a failed coolant gauge in the instrument panel of my 84 vanagon.  the saga
started when i swapped out my instrument cluster that had various cracked
and broken plastic hold down parts with one i had on the shelf from one
of my old vans that i parted out.  so i swapped in the cluster and fired
it up only to remember, or more precisely to be reminded that i had been
having coolant gage problems with that van before i parted it out.  i knew
form the old cluster that i took out that the vans system was operating
correctly.

so that lead me to suspect the coolant gage and the voltage stablizer.  i
checked the voltage stabilizer and it check out fine.  a note here that
both the clusters that i have have different voltage stablizer set ups
than is pictured in the bentley manual.  the bentley manual show a voltage
stabilizer with three pins and three connections on the flexible plastic
circuit board.  in reality the voltage stablizer has three pins but there
are only two plug in connections on the flexible plastic circuit board for
it.  anyhow even though the voltage stabilizer checked out fine i
swapped it with one i had on the shelf for fun, there was no difference.

so that lead me to change out the coolant gage for the coolant gage in
the cluster that i had removed.  i did that and everything is in fine
working order now.  the original symptom was that the led flashed
constantly  but the gage needle responded correctly most of the time.
some other good information on this topic was posted by mark drillock in
the archives recently and can be found at this address.

http://gerry.vanagon.com/cgi-bin/wa.exe?A2=ind0403A&L=vanagon&P=R3187

jonathan