I was trying to do some troubleshooting as described in this thread: https://pinside.com/pinball/forum/topic/most-flashers-not-working-on-big-guns#post-6070064

I'm not sure when exactly this happened, but at some point I noticed all the controlled lamps were locked on. I turned the game off and on and nothing changed. I then unplugged the LED OCD board, and the controlled lamps returned to normal, save for column 7, which wouldn't light at all. Previously I had an issue where lights in column 6 would light adjacent lights in column 7, but lights in column 7 could also light on their own. Now they won't light at all.

After this I plugged the LED OCD board back in and the controlled lamps all locked on again.

Anyone have any idea what could be going on? The board had been working perfectly since I installed it almost a week ago. Unless column 7 being out is causing the board to do this for some reason I'm not sure what else I should check. The lights on the board are all behaving as they should too.

Edit: I contacted LED OCD and was told that a light column being out can cause the board to fail to sync. I've repaired the light column issue by replacing Q54 and everything is back to normal!