I have a Zaccaria Locomotion (Gen 1) and I did a quick tidy up for acid damage on ICs 4 and 5 when i picked up the machine a few weeks ago, and it did work (previously wasn't with no credits being able to be put up, and some other switches not working) – then it stopped allowing switch inputs (ie: can’t coin up or get into tests), so I replaced the sockets of IC 4 and IC 5, and there is no change - still not working. I have buzzed all traces and think its OK, but it was a bit messy. The one thing that is strange is the game over light flashes continually on power up – not sure if this indicates anything - there was a reference on a google page to Gen 2 games to a flashing game over – see below:
For all audits, make sure to clear them (hold Start button until each
one clears). For all settings, set the option, even_ if it appears to
already be set to the value you want. When you exit to game over, the
Game Over light should be on solid. If so, the game thinks that the
contents of RAM are good and is using them. If Game Over is flashing,
the game thinks the contents of RAM are bad, and is using the "country
defaults" from the DIP switches.
The 5101 RAM is socketed and I can’t see any corrosion near it.
So any tips or ideas what to test to try next?