My south park switch for cartman hole is not working. I have changed the switched and traced all the wires. Everything is good on playfield side of the game.
I used a jumper wire to narrow down that problem is on the board.
I changed the 8 transistors, the lm339n chips, 74HCT273 at u203, 74HCT275, And 68B09E's. None of these changed anything. Occasionally the switch does work with jumper but often take 10-20 trys before registering.
The guy that helps me fix them finally said he may have changed that switch (soldered with game on)
That has happened to me in the past but usually the lm339 fixes it.
Can anybody help????