Quoted from KenLayton:Maybe one of the two 6821 chips is going wacky.
If they are AMI chips, it's even more likely since that brand is more failure prone than other brands.
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Quoted from KenLayton:Maybe one of the two 6821 chips is going wacky.
If they are AMI chips, it's even more likely since that brand is more failure prone than other brands.
Quoted from rufessor:So- it sure sounds like something that is warming up and works better hot.
It could be a component, chip, cracked solder joint, bad socket, a cut trace--any of those things will expand or contract due to temperature.
However, the nature of the symptom can help narrow down where the problem might be.
If you can get into diagnostics and into the switch test to see which switch is being detected, that may determine what pathway to follow on the board, if it's simply not a PIA chip malfunctioning.
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