Barracora is a Williams System 7 game and I am having a strange problem. Everything works perfectly on the game except one coil.

When the game is in attract mode the lower drop target on the right side keeps firing. This game has a coil on each drop target to raise it. When you enter test mode the coil quits firing and all coils test correctly including the one I am having trouble with.

I unplugged both row and column switch connectors to eliminate a switch issue. I also verified that the U5 PIA output driving the coil transistor circuit was toggling to turn the coil on/off. I replaced U5 PIA but it did not fix the issue. It is like the CPU is telling the PIA to fire the coil.

I guess my next step is to burn some new ROMs.
After that maybe replace the CPU.
Then look for opens/shorts on the CPU/PIA address and data lines even though I do not think this is it since test mode works.

Any help appreciated...
Big Bob

Turned out to be the game ROM.