Lost all high power solenoids seemingly out of nowhere last night on the game. After finally figuring out that the manual got F104 and F105 backwards, I narrowed down the issue to F104 being blown.

I replaced it and ran through coil test one by one and the auto plunge coil locks on in test and causes the fuse to blow. If I ground the TIP102 at Q79, the coil will fire but locks on. I’m assuming this means that Q79 is bad? and maybe the TIP36c at Q80?

I don’t have these on hand so I’ll need to order them to replace them so I just wanted to see if I was on the right track or if I was over looking anything obvious.

Solved thanks to this thread from 4 years ago:

https://pinside.com/pinball/forum/topic/bsd-opto-problems-holy-carp

After double checking for shorts everywhere, I followed suit and opened up the apron and shooter coil. Sure enough one stray coil "thread" was just barely touching the coil bracket causing the short.