I have a 1976 Bally "Aladdin's Castle" pinball machine where, when you enter the maximum credits, the coil for the knocker in the center of the back box stays energized and I have to turn off the game.

Is there a switch that cuts power to the thing when you hit max credits? I don't see the knocker in the schematic. I would think the leaf switch that the credit wheel pin hits, normally closed, would open and cut power to the knocker?

https://www.ipdb.org/files/40/Bally_1976_Aladdin_s_Castle_Schematic_Diagram_continuous.pdf

IMG_20220711_163340945 (resized).jpg

Thanks for the schematic picture. Is that the same switch I mentioned in the original post (not home now)?

That switch is definitely closed at max credits.

This seems like a physical thing, rather than electrical. The pins on the unit make it stop where it is and the switch is closed. Is there something that can be done to remedy this?

Every coin/credit you put in the machine the knocker goes off and that switch briefly closes. When you hit max credits, it stays closed and I need to shut the machine down as the knocker is stuck on.

I think the whole 'credit limit switch' thing is wired wrong. Stay tuned...

Yeah, it works fine now. The 'credit limit switch' was not doing its job, someone wired it wrong.

Thanks everyone!