Hey guys! I screwed up! As some of you might have seen in a few pinball groups on Facebook, I recently restored a Williams Joust machine complete with new cabinet and a mega shop. 40 pin interconnect was changed, etc. Let me tell you, no detail was left out as I wanted it perfect. Umm, well one detail was left out...I didn't run a 3" piece of ground strap from the main AC filter case to the rest of the cabinet. Yes, all of the cabinet was meticulously run with ground strap but it was useless without it being connected to the main ground. Totally an oversight on my part and I take full responsibility for my error!
Here's what happened:
Game booted and played fine for about 10 games and then I noticed that all controlled lamps beside those in Column 1 were out. Strange but it didn't affect the game otherwise. I power it down so I could investigate. Found nothing out of the ordinary as far as wiring shorted or broken so I powered it back up. Still played great! Turned it off and left it for a few hours. Upon powering it up later, all solenoids (besides the flippers) fired once every 3 seconds and repeated. Game doesn't boot and just keeps firing the solenoids!! G.I. flashes at the same rate as the solenoids as they fire.
My question is, am I on the right path knowing none of the boards or playfield components were grounded? Which chips do you think are fried after not being grounded? The PIA's, the 7408 gates? I'm pretty clueless when it comes to testing these boards (System 7).
Any ideas are GREATLY appreciated!