Thorly is asking about my BK. Thank you to everyone who has responded. I cut the veristor out of the circuit and it still is in the same state. Any other suggestions for a BK system 7 stuck in blanking?
I found a coin switch that may have been stuck on after reconnecting, but have since fixed that. The cpu board was rebuilt and working before this. We checked the 40 pin interboard connector and get continuity for all pins.

Thank you! How do I check this 555 circuit? Where is it located? I have seen this before on Mark's Guide, but I don't even know where to start checking for issues. I am familiar with the driver board, but the CPU board is new to me. I have a DMM and a logic probe.

Hit the line filter, but nothing else. I did notice that a coin detect switch had excess solder on it, which would have caused issues to, but I have fixed that and there is no change.