I'm very near the end of a complete Gottlieb Haunted House restoration and I've run into an issue I can't resolve. Everything works - displays, sound, scoring...except solenoids. Basically no flippers, no slingshots - nothing solenoid controlled. I've traced it to the game over relay not engaging when a game is started, and if I hold in the relay manually all solenoids (pop bumpers/slingshots) work.
If I ground the Q1 transistor, the relay engages as it should. I originally thought the transistor was bad (tests good) or the driver board had an issue, so I swapped my Black Hole driver board but got the same result. I then swapped the BH MPU along with the driver board (changed the game ROM), but got the same result again. Self-test will activate the U relay but not the Tilt or Game Over relays. I can't figure out why the game over relay isn't latching when a game is started.
FYI - all ground mods completed.
TIA for any help.