I am pretty much lost. I have looked and looked but cant seem to find any ideas on what to try next.

So here is the problem. I picked up a scorpion (system 6). Game boots up and I am able to play. All the coil are working except the ball kick out to the trough.(6 in the manual.) So I did the normal stuff, reflowed the solder on the 40 pin. And all of the pins for the other plugs. I have replace both the pre driver chip and the driver chip. Still not working. I am not sure what to test next or replace. Anyone have an idea?

Just a guess. Working on new games. Usually is a transistor that went bad. I do have 30 volts at the coil. How do I ground the transistor tab? On the board?

Awsome. Didnt knowing could test the transistor like that. Once doing that it fired. So guess it's the logic chip then.

Thanks. I will order a probe.