The term 'flupping' was originally coined as a specific appellation for a specific diode-related fault in the PAB of early Macintosh models, a fault that may precipitate capacitor failure, perhaps, but is not the primal cause of the problem. Some of what you described above is much more like 'flopping'—for the sake of a descriptor—than flupping. However, tomlee59, in his paylife alter ego, some time ago posted some avenues of approach to a problem with some kinship to yours. If you also look for the schematics and narrative that tomlee59 has lodged here and elswhere for the same Macs, you should be able to check the PAB with some certainty of outcome. You are the man on the spot (in both senses), so you will be able to apply that info. with a good chance of a successful outcome. Good luck.

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