I just picked up a project Fish Tales that was being tossed in the garbage. It has been folded up for the past 10 years in storage and the batteries which expired in 1999 were still in it. The holder was a bit corroded but nothing terrible and a few of the components had a bit of acid creep but not nearly as bad as I have seen in the past. It cleaned up very easily and I installed a remote holder.
Anyway when I booted the game up it of course wanted me to go into the diagnostic report. I opened the coin door and none of the diagnostic switches worked nor the coin switches. After looking for shorts I pressed the diagnostic enter switch again and the game freaked out and start adding credits and cranking the volume up and down on it's own. After pressing it again it briefly it went into the settings menu for a split second but then set the volume to zero and went back into attract mode.
With max credits added unintentionally I tried to start a game and nothing happened. So back to the coin door I went and this time around every button inside the coin door now added credits including the volume buttons. The odd thing is that sometimes the buttons respond (improperly) by adding credits and sometimes they will go completely dead. The coin switches will sometimes add credits too but only when the diagnostic switches are registering credits as well. Once in a blue moon pressing enter will go into the menus but shortly after it moves the volume up and down on it's own and then starts adding credits again for a bit.
Aside from looking for shorts I saw that the coin door switches are not part of the matrix but on a dedicated circuit. J1 and J3 on the coin door interface board connect to J205 on the CPU which are controlled by U16 and U17? I'm not sure if I'm correct there.
Pardon my ignorance but I also noticed the coin door lights go on and off with the GI in attract mode and that when the game is flipped on for the first time it appears to go through a brief ball search everytime for a few seconds. The kick out holes actuate one and the reel mechanism goes through a few cycles. I am not sure if this is normal or not for this title. All 3 balls are in the trough. Sorry for the long winded post but I did not know how to briefly describe what was going on. Thanks in advance!