I purchased a Bally Space Invaders that needed a bit of work and I almost have it running except for one thing. I need some help trying to figure out why one solenoid is energizing. It does it continuously during game play and is scoring the pop bumper each time. When I put the machine in self test, it still continues to energize during the lights only test, displays only, sound, etc. Ironically during the solenoid test it seems to energize less but still has a tendency to energize more than when it should. When I do the stuck switch test it tells me one of the stationary targets is “stuck”. I paused from the solenoid testing to fix that stuck switch (#17) and it didn’t appear to have an issue. So I looked at one of the other stationary targets (#15) to make sure they looked the same. When I re-ran the stuck switch test it now tells me #15 is stuck and I can’t find anything different with it. (Super frustrating) The switch that is part of the pop bumper is a higher number. Without fixing the lower ones, which now I’m lost at, I can’t check to see if the pop bumper switch is showing to be stuck.

Is this something wrong with the boards. The pop bumper switch wires connect into the Aux. Lamp driver. The MPU self check at start-up appears to show it is in good condition. And I don’t see anything obvious with a battery acid being to blame.
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I just did some further looking at the MPU and it does have some acid damage. Would this probably be the issue, even if the switch ties to the Aux lamp driver?

If it were simply a bad capacitor, would it be tripping during the self test sequence of lights only, display only, etc? Right now the solenoid is firing during these self tests.