Has the battery leaked on the MPU?

Another problem area is the daughter board on the MPU that holds the game ROM.

http://pinwiki.com/wiki/index.php?title=Gottlieb_System_80

If theres no battery damage make sure the reset board is plugged in (small circuit board next to mpu that has wires coming off the mpu to it) then while the machine is on push on the daughter card (small circuit board soldered to mpu) with your finger and see if that does anything. Sometimes you have to hold pressure with your finger for it to boot up sometimes you don't, if it boots up then there is cold solder joints on the underside of the daughter card.

system 80B boards don't usually have a problem with the daughter boards. They have thru holes and solder pads on both sides of the socket, but no harm in trying what you said. If any of the RIOT chips are very hot, there bad. I've repaired many system 80B mpu's, they are not hard to troubleshoot, logic probe or scope is pretty much required. PM me if you have any questions.

I got the same issue now with my robo war just sort of started, gone thru the basics, re pin the connectors clean the fingers on the board, check power, nothing really jumps out and says it me I am broken, I am leaning toward s a chip on the mpu but I am not talented enough to know how to find it.

gary

please help kind at a stand still, heres a small up date, what has quit working is the # 3 drop target and the rh roll overs and the top 4 rollover. now the fun part when the game has been off all night I first turned it on it worked like a dream no problems for about a minute or so then it slowly started to fail but just the items noted above obviously heat related but where do you start.
thx gary

ok great update I got it all working, turned out to be a connection issue on the j6 edge connector the fingers on the board needed to be retinned all is great or was. now I did a dumb thing I put one of the game proms in the wrong way and toasted it what a dummy I am, anyway where can I get a set of game proms for the robo war game. your help would be appreciated