Newbie to the group here. I'm looking at a nice 1991 Bally Party Zone in my town. The game has been HUO for the last 17 years and has sat unused for the last 7 years. The owner plugged it in and turned it on, and we got playfield lights, head lights, flipper action, and some "status" messages across the dot matrix display. The game would not start or kick up a ball, and the owner said it is set up for free play. (A coin made no difference.) The game is in nice enough shape that if we can get it working, I'd like to own it. There's no manual or schematics. (I would not be able to read schematics, anyway.) Is there any guidance out there? Thank you for your consideration.

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I did look at the cpu board. No evidence of acid damage or the like -- in fact, the spots for batteries were empty, so someone knew to pull them. The owner said that the batteries are there to retain high scores and such. I wonder if the absence of batteries keeps the game from starting... sorry for the lack of pics, though I saw no stains or crusty stuff or brown spots on the boards.