Okay so I know I'm gonna sound like a complete newb dummy but...which pins/connector do I check with a Multimeter for the display 100 Volts? Right now the biggest priority is getting that working since the game does appear to work normally after a few steps.
Here is what I've done so far:
-I replaced the F2, F3, and F6 fuses, one of which is tied to the dot matrix board (which still does not work)
-The battery holder appears to be shot, as the contacts for the negative/positive sides are corroded/rotted. This may relate to the issue that keeps happening.
When first turning on the machine, it goes into a diagnostic mode and a game cannot be started, and the playfield does not light up as in attract mode. The red lights on the MPU indicate that things are "normal".
-If I press the diagnostic buttons in the coin door, I hear it register the input, but since the dot matrix doesn't work i can't determine which option it's on.
-If I then press the CPU button located on the MPU, the machine goes into attract mode, and the playfield buttons light up.
-When I put in quarters (it's not set on free play yet) and start a game, everything appears to function normal (I hear the "Uh Oh, looks like rain, followed by the thunder and the music and ball kicks out)
-If I play and the ball drains, I can hear the score tallying up, and then the next ball kicks out. However, sometimes the game may completely reset and I'll hear the "Uh Oh, looks like rain" again, and the music will stop. Other times, the game will just continue on infinitely, never stopping the game even after 3 balls have drained.
So what I'm trying to see is what to test or pinpoint first based on this behavior of the machine, which I think would be power to the display.