autocheck woes on 90 200

[Mike Posner]

Constant warning light for coolant level/temper

ature. Temp and coolant are fine.
Prior post by Cobram indicates his problem was not fixed via replacement of
reservoir,

wiring check, multifunction switch. He finally replaced the board from a na
car, fixwd the
problem but had to sacrifice accurate boost measurement.  Has anyone fixed
this problem at the component level, i.e. resoldering , new caps or
resistors?  This is an expensive fix at the dealer, $700-$1,000 as I recall.
I think the lower price might be for a rebuilt unit suggesting
that some one knows how to repair thes board.   TIA   Mike Posner,
Encinitas.

90 200
83 coupe
89 Pontiac TTA
84

 Fixed it by replacing the multi funcion sensor. Diagnosed
 by dxing the plug to the sensor, stopped the flashing
 auto check, eliminated the auto check board as the cause.

 MP.