I have one row and column out on Charlie’s Angels; the circled switches in the photos. I checked all the diodes and they all seemed fine, so I’m assuming it’s a chip on the board at this point, either Z8 or Z9, based on what I read at: http://www.pinrepair.com/sys1/#smatrix

This is the first time I’ve used a logic probe to test a chip, so I wanted to see if anyone can tell me the best way to do this? The instructions I found online weren’t too clear. Or if there is a better way...??? I just have an old logic probe, a Knight 625, but hopefully it will suffice. Or am I even on the right track here? This is a new system for me. Thanks in advance... maybe it’s something easier?

Video of switch issue:

6F2FEA41-540E-47AE-AAD9-7601C60D2035 (resized).pngF82EC54A-2CA7-47E5-BD46-68F0C64AF2E5 (resized).jpeg