- Game is set to free play, however it automatically "starts" as soon as game boots or a game ends, as if someone is always pressing P1 start
- P2 start input is 74LS386 @ 9F pin #12, tested it, it was high (which is normal)
- P1 start input is 74LS385 @ 9F pin #14, tested it, it was stuck low (it should only be low if a person is pressing the P1 start
- turned game off and checked continuity from 9F pin #14 to ground (looking for a physical short)... no continuity, which means the chip is probably bad
- Pulled the chip, socketed and replaced.
- Game works properly!