I’m stumped. Bad PIA?

Picked up a Game show plays fine except some of the flashers not working correctly. In coil test, some of the flashers flash when they’re not supposed to. Some of them don’t flash at all. I have traced wires and believe the terminations are per the book. I did find evidence of some wire hacks and fixed them. I’m wondering if it could be a bad PIA on the MPU. Any suggestions?

The A/C relay is activating. I am attaching the results of the coil test. As you can see, coils are activating that shouldn’t, or should I say, some (most) flashers are activating when they shouldn’t and vise versa. Additionally, I should mention that the BG GI’s are on throughout the entire testing except when they flash on and off with test 1A outhole.

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Ok. May be on to something here....The wires at the Aux Driver Power board at J11 are not per the book. I know that sometimes the book is wrong....but???

It does appear that someone reconnected (smashed) the wires into the IDC connector (previous work). I hesitate to change to the book description without confirming the book is correct. I'll look for backbox pics online see if I can confirm. Comments??

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Found a good pic in the archived ads. Looks like my game is wired wrong. Will replace the connector and report back.

Replaced the J11 connector. Still not working correctly

This is the latest coil test results. So many things not working! I checked each and every connector on the AUX DRIVER BOARD, THE MPU, AND THE INTERCONNECT BOARD. All the terminations/color wires are per the book.

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It's getting worse! The A and C tests are working backwards. In coil test, when the C side is testing, the relay is not energized. And when the A side is testing, the relay is energized. What could cause this?

Can you elaborate? What would cause multiple coils to activate if the wiring is correct?

Checked and don't see any. I found something I think is wrong though. On one side of the A/C relay the contacts are measuring closed in both positions of the switch. In other words, when I actuate the relay manually, the contacts are visually open, but there is continuity across the open contacts. Could this be a short somewhere? When I pull the connector at J11 the contacts no longer measure closed.

the A/C relay wasn’t switching at all (among other issues). Replaced Q8, Q4, and U18. All tested bad. Replaced with TIP102, 2N4401, and 74F08. The solenoid PIA is soldered in. I have been putting off replacing it. More thoughts?

Yes. The relay clicks on and off. It didn't before, but I replaced the TIP102, 2N4401, and U18 and now it is switching. In coil test, when it shows 1A for instance, the outhole energizes, then when the relay switches to C, the outhole energizes again. What appears to be happening is that the relay is operating backwards. Maybe the issue is that A and C busses are both energized because there is a short. Perhaps?

The game was working with the boards in it except that some of the flasher lamps were not flashing at all, or sometimes when they were not supposed to. At some point in my troubleshooting the AC relay quit switching. That's when I found the bad parts and replaced them (TIP102, 2N4401, 7408). Now the relay switches but backwards...Deenergized relay the A buss is energized. Energized relay the C buss is energized. That's backwards to how it is supposed to be. I have pulled the MPU again and do not find any solder splashes. I did not change any wiring to cause this anomaly.

The book calls the Aux Driver board to be D-12247-566. What is installed is D-12247-559.

Doesn't explain why the AC relay is operating backwards now when it was correct before since I haven't changed any jumpers. But ok, one issue at a time: How do I determine what the configuration should be? See drawings. The dotted lines (jumpers) don't seem to mean anything specific.

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I didn't know the jumpers were listed in the parts manual. I was looking on the schematic. I have verified the jumpers are correct on the board I have.

Now I am confused by your posts. I didn't quote part numbers from Banzai Run. The Aux driver for that game is totally different: D-11813-566. I have D-12247-559. My manual shows I should have D12247-566. If I should be using a different board, can you possibly tell me what games goes with D-12247-559, if in fact it won't work in my game.

Yes, that's what is was doing at different times of repairs. Now....I swapped out the U18 (7408) and it wasn't reversed anymore, but now, again, the relay is not switching. Let me try to clarify:

In coil test...
When I test 1A, the display shows 1A and the outhole fires (along with some lights).
When I move to test 1C, the display changes to 1C, but the outhole fires again, along with GI lights.

Move to test 2A, the display shows 2A and the shooter lane fires (along with some lights).
Move to test 2C, the display shows 2C, but the shooter lane fires again (along with some lights).

etc....
In test 12, the relay is not switching anymore.

I checked the output of U18, pin 6. During relay operation (switching), the output of U18 does not change. Would this point to U10 being suspect?

Thanks for your continued interest and help!

I've made some progress. I replaced U10. Now when the AC relay switches, the coil firing is not repeated on both A and C tests. The issue now is that some things fire when they are not supposed to, and some things do not work (flash) at all. Back to looking for a wrong wire (s) or short? Perhaps another bad chip? The wrong Driver board? The wrong interconnect board (it has an aftermarket one installed).

Resolved. The manual has J11 on the interconnect board backwards. That was part of my problem. The other issue was the new Pindorabox interconnect board had the wrong resistors on it. The part number was correct for my game, but had 5.6K ohm resistors instead of 5.6 ohm.