I'm doing a full strip down playfield cleaning/rebuilding. Everything is working but stumped on flashers. Was fortunate to have a few Sys11 machines over the few years and never had much go wrong. This is a super nice original Black Knight 2000 with original and no hacks anywhere on the board.
This is what I tested and confirmed so far. Everything else works on game 100%.
1. A/C select relay is clicking in test. I can actually see it doing so as it's a clear cube relay.
2. When grounding Q8 I put the machine in coil test mode. All flashers work with exception of two by flippers. (Owner said this was happening before so may just be the software or another issue.) So I clearly have power.. Assume AC relay or its driver is why I have no flash lamps since they’re all on C and I have all A solenoids working fine. Owner confirms they were working with exception of the two lower at flippers.
3. Checked all fuses while in backbox by testing them with a meter out of the holders. Found a few that were oversized and put original value fuses in their places. F2C checks out fine when grounding Q8.
Maybe I'm confused but I'm looking at the clear cube relay on the AUX board. There's also a yellow one on the CPU board. Which one should I be checking and am I on the right path or is there something else that actually is driving the A-C select other than Q8?