My Eight Ball is doing some strange behavior that I can't find an answer for. The game has worked well for a long time. It does have the standard corrosion damage in the battery area, but nothing that has affected performance after I cleaned things up right after I purchased it. It has worked well for over a year.
I did just remove the MPU and move it around to another pin for testing out the other pin (I needed a known good MPU). Now I am getting weird behavior, perhaps unrelated to the move but I figure I should mention that I did it.
When the pin is cold and I start it the game will fully boot, all 7 flashes on the MPU. But the displays will all come up weird, numbers in the wrong spots and many of the controlled lamps on the playfield will be lighted that should not be.
If I start to play a game everything will work (coils, kick back lighting, etc), but many of the controlled lamps that should not be light will be lighted and the displays will not score correctly. Like Player ones 1,000's position will also show up in the player 2 far right scoring position simultaneously. Other problems as well, the displays will be flickering, all displays. No nice steady, numbers.
If the game is on for a while and I try to restart it I will only get two flashes on the MPU. That means either the U8 chip, U8 socket or U19 is bad according to Clay's. I have swapped in a known good U8 chip and the MPU will still not boot (only two flashes) until it sits around for a while to "cool" off.
I hate to start throwing parts at the pin without a plan. What will cause both the controlled lamps and displays to totally wrong? I can put in the new U19 and U8 socket, but would either of those cause this problem? Could I have messed up a trace when moving the board that would cause this to happen?
Thanks for the help.