Quoted from dementedwarlok:I have to ask how you know lol! Hope its a chip that is removable
It's llikely the U20 chip.
https://www.pinballlife.com/williamsbally-uln2803a-switch-matrix-driver-chip.html
I did a similar thing on a TZ I was babysitting. I turned the game off, but didn't wait long enough (went in with a nut driver) and ended up blowing that chip. It was previously socketed so it was easy to replace, but yours may or may not be.