i learn something new every day...
was playing my jacks open last night... in the middle of a game, the drops stopped scoring (the score motor rotated, but no scoring happened).. i turned it off, and when i turned it back on (gi lights turned on) and pressed the start button, nothing happened... not even the start relay would engage...
thought, "let's check pf power first, since it is easy, and maybe something is questionable there"... nope, fuse measured good, and i get 27.6v across the fuse holder...
scratched my butt for awhile, and started looking around... went back to the head, and while poking around back there, the machine fired up... had my wife play it while i watched, and it stopped scoring again... this time i saw it though... the wiring harness moved and pushed up against the 1000 point relay, and was holding it closed... pulled that away, had her restart the game, and voila, no more problem...
i'm not completely convinced that there isn't something else jostling around that is the real culprit on the "no start" problem, as the startup sequence indicates that the s relay should fire before the score reels even know the game is being started, but at least it works now...