Quoted from boscokid:
Chad, I would not buy a new MPU as I don't suspect that is your issue.
Have you tried wiggling the power supply connections while the game is on? My guess is you are losing either power or ground from a loose connection or short. Can you post your voltages from the PS test points and maybe post a picture of 3J5 and 3J6 (top of PS board) from front and back. Did you repin any connectors on the PS? Verify that board is screwed in tight and the ground is good.
Someone above mentioned checking all your coil and switch diodes, did you get a chance to do this yet? It's always a good idea to do this I've had a broken diode cause all sorts of weird issues but never a total shutdown.
Intermittent issues are the worst; just when you think it's fixed..........
After thinking this out further, I also agree that a new MPU isn't the route to take since I sent the board over to Ed who stress tested it for days with no issues. Instead of waiting and trying to track this problem down to a new PSU, and the fact I'm keeping this game forever, would it be wise to go ahead and replace the PSU for the hell of it and then rule out all of the stuff related to power?
As for checking every diode, I believe I did this and didn't notice anything broken.
As for the flippers not working, I don't recall at the moment. I'll keep playing it and the next time it dies I will report back.
All that was done to the PSU was install all new caps, which I didn't do the install. Does installing new caps also require re-pinning or is that another step? I know for a fact my guy only put new caps in, but I don't know what all that entails.
For the voltages, do you want a reading now as the game is working as intended, or do you want a reading once the game dies? I have not wiggled any PSU cables while the game is on.
Quoted from snyper2099:
I had this happen on a game with a new power supply once (TFTC). The game would play for hours (sometimes days) on location and just crash for no reason at all. It was so annoying. Every socket and power test point was checked and all were fine and the test points never fluctuated thought the months that the game was on location. It turned out to be a flakey EPROM. I burned new ones and it solved the issues. I would at least look at replacing the game and sound EPROMS before you buy a new MPU. They are not that expensive.
Are you able to burn these ROMS for me?