Nothing missing. I guess they planned on using switches for the multiball count. Instead they used an opto board to detect ball count. Top coil is knocker.

I have a switch issue that maybe someone can help me with. I have been getting random multiball without earning it. I have checked diodes and switches. The opto board is working correctly and has solid connections. I have found out that when I manually push the Treasure 50K 2 & 3 together at the same time all the Release Multiball Memory lights down by the flippers energize and I get multiball!? Sounds like a matrix issue but I can not figure it out. I wonder if the ROM is bad? I didn't find any other combinations of switches that would do the same thing. What do you guys think?

Found only tilt bob registered correct but then started registering different switches one after another!? With lead held against brass rim. Checked diode and only found lead bell piece itself was not tight on brass rod. Tighten and retested. Showed correct over and over when held against brass rim. Problem still accured. Removed opto boards and inspected under magnification. Suspected a loose emitter diode and resoldered. Also checked resistors and reinstalled. Game plays fine now! The opto boards worked great during switch testing. I ordered all replacement components to have on hand just in case. The great lakes modular replacement opto board set says it works for this game but it definitely does not.
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