Quoted from alb0711:Voltage at 12 volt regulated measure 12.1. I removed the ribbon cable from the 8-driver and no change.
During one of the boots some switches in row 4 showed open. I triggered the left sling and it kicked back. The machine then told me there was a ground short in row 4 and all of the row 4 switches then showed closed and would no longer respond.
I've also noted that sometimes at boot the clock will turn and turn and turn, sometimes for a minute or more. While it is turning the switches on the coin door don't work. Once the clock stops turning the switches work fine.
It seems like my MPU acts fine when nothing is plugged in but then gets flaky when its under a load. Anybody run into this before? I'm thinking about pulling the MPU from my gilligans island and trying it in twilight zone. I just don't want to fry another MPU if my twilight zone really does have playfield switch short(s).
Did you try testing the board with the cables disconnected using a diode and jumper cables? Might be easier than swapping it with the one from G.I..
Grosse Pointe Farms, MI
