i don't a good enough schematic to locate controller chip for switch 41,42 and 43 for some reason they all quit working at once which leads me to think that it is a ic chip that went bad since no broken wire no loose diodes in any help would be greatly appreciated THANKS!
System 11a MPU, right? Sounds like you may just have a bad transistor on your switch matrix. Probably not an IC, or more stuff would be wrong with it. If you don't have a schematic, there is a quick and easy way to find out which one. With the machine on, set your multimeter to DC volts. I use an alligator clip and just connect the negative probe to the ground strap so you don't have to hold it and potentially slip/damage more stuff. Check the right/top leg (collector) of each of the 2n3906 transistor over on the bottom left by connectors j10, j11, and j12. You should see a small voltage on each (I think like .5v). If you see zero volts on any of those, it is shorted out and needs to be replaced.
cool yeh i have replacement parts so that's no prob the reason i thought might be an ic is usually when mutipull things go wrong on my firepower that's what it ends up being usually though it is 4 things not just 3
That is common for problems like that and random resets to show in multi-ball because of the same targets being hit on that line in the switch matrix. All kinds of crazy things happen when one of these pre-drivers for the TIP102s blows. Easy fix though.
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Hilliard, OH
hope it fixes it