I think that you should test the temp sender in the radiator.  I figure it
is always open in the loop that turns on the fan.  I would think a test for
this would be to unplug it from the radiator when car is cold and see if it
is off.  If it stays off, you found the culprit. Then it is a easy
replacement and you are on your way.

As to your a/c to determine if it is off, see if the compressor cycles when
you think it is off.  with my vans, the fan blows when the a/c is on, but
only when the compressor cycles.........otherwise it is off........so when
temp is turned on low for the a/c, the fan cycles on and off.  When i have
a/c on high, the compressor is always on, and so is the fan...........

Adam P
Charleston,SC     Coburn, WV
81  Westy "The Brick "
70 Single Cab "Whitey"
74 Beetle "Ol Yeller"
73 Transporter (STILL at paint shop)
1988 Vanagon Wolfsburg
1976 Transporter (New CA bus)
1974 412 "Goldmember"
Used Vanagon Parts for sale (mostly aircooled)
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