At 02:56 PM 9/29/2002, George Averill wrote:
>There is one more part of the circuit you haven't replaced.  Packed into
>the back of the temperature gage is another integrated circuit (chip and
>other components).  It can go out too.  The temp. gage can be
>replaced.  That will probably cure the problem.  The last one I installed
>worked fine for about 6 months.  Then it quit again.  I haven't had the
>time to order and install another, but will do that one day.
>
>There may be another problem that is causing the temp. chip to go
>out.  Voltage surges may be occuring in the 10v regulator circuit.  VW put
>out an upgrade requireing that a diode be installed in the 10v regulator
>circuit to stop the regulator from blowing out.  I have a copy some
>place.   Anyone have any ideas on this?

The usual failure of this circuit involves the large capacitor which is
supposed to terminate the initial blink-test on turn-on.  It's a
high-impedance circuit -- if the cap becomes leaky and/or if leakage paths
develop on the board, it will never charge to a high enough voltage to make
the light stop blinking.  Replacing the cap will fix it in this case, but
it's a nuisance to get to.

david

--
David Beierl - Providence, RI
  http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"