I have some switches that do not work on my Skateball. It appears that an entire row is out because the middle drop targets of the middle and top drop target banks do not register. the “A” rollover and left inlane switches also do not work.

All of these switches were working recently but just stopped. The switches do not show up in the switch test.

I rebuilt the connectors on the MPU. I also swapped out the original MPU board with an Altech board. The switches still don’t work. They worked for a ball or two after the swap then stopped working again. After I switched to the Altech board the saucer and the trough switch started to act up randomly.

I also rebuilt the connectors on the rectifier board and installed a brand new Weebly rectifier board.

What should I look at next? Diodes?

There were no switches that were stuck on.

I didn’t check to see if any switches registered the wrong number, I will go back and check.

I just repinned the J2 connector. I will have to double check #10. Maybe I boogered something up.

Thanks for mentioning the coin door. It turned out to be the easiest solution. The credit switch that someone MacGrubered coming out of the coin door was shorting out against the door.

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