Judging from that picture (tough to fully see online), that board needs quite a bit of work. The batteries leaked and had a party there. Headers, the whole bottom row, and most likely more. It acts like a very slow burning fire. Even if you find the exact thing causing the current problem, it will keep spreading. Sorry to be the bearer of bad news.

Yeah that board is a hot mess and the corrosion is probably the issue and it will only get worse. Consider replacing it, you can them for like $200. I'd just replace it for an easy and quick solution, and it's relatively cheap for what you get.

https://ksarcade.net/rottendog-security-cpu-a-17651-mpusec.html

If it weren't for the board my suggestion would be check every switch in the slam tilt column/row as it's probably shorting.

That probably IS the reason, except that the short is in the board not the playfield. Either way that board needs repair or replacement.

Don't be annoyed or upset, it's not the end of the world it's just pinball and this is what pinball does. I've lost count of the 90s games I've gotten in with a board that looks just like that. If I'm not buying from a collector, I expect it now. And even if I am buying from a collector it's still like 50/50.

It looks like every single resistor in that line of two rows has been hit. Look at the dark solder dabs. They should have a shine or at least silver look to them. Those look darkened.

Yeah, you have battery damage. A lot of it. Send it off to a professional to get fixed before that spreads more (and it will).

No, those are all a different earlier board system.

I don’t know what you need to confirm. 100 percent that board needs to be repaired or replaced.

Also spend a few bucks on a chip puller, which you will probably need depending on which new board you order.

World Cup 94 is WPC-S so you can swap U6 and U22 to see if the problem persists.

The other location that can often cause grief with column/row shorts is the opto board (if a machine has one). Dirty Harry has a 16-opto board. You can disconnect J5 from that board (to isolate it from the switch matrix) and see if the problem persists.

Edit: I should add that I concur with everyone that is saying that board needs repair. In my opinion the alkaline corrosion looks to be shallow but widespread. It is the likely cause of the problem but if you send that board out for repair and the problem is on another board you will be sending that other board out for repair (or replacing it with a new one).

No confirmation of that type necessary. That board is a mess. Send it out to be fixed up and arrest that corrosion before it gets worse.

Maybe check plugs on the coin door interface board. I believe both areas of concern go through that board.

Make sure the plug on the opto board is not a pin off.

Have you checked all the wiring on the coin door and components? I had a similar issue when two wires came off of their lugs on the switches for the coin slots and would cause some funky stuff to happen with the game and service buttons.

Chris Hibler ChrisHibler comes highly recommended by a lot of people.

This is because the game cannot see any of the optos (they are disconnected). It is expected. Enter test mode and select any switch test (edges or levels). Note which switches are closed (by default). You are looking for entire rows / columns or patterns. If you cannot enter test mode then you have a bigger problem that requires the CPU board to be repaired (or replaced) first. Swapping in a known good CPU board can help diagnose and isolate.

As mentioned it's likely the CPU board is the cause of all your problems but it is also possible that you have another problem that is being masked by this problem. You can differentiate (or exclude) that by swapping in a known good.

chris will just tell you to replace it i imagine. pretty rough!

Jakers I can take care of that. It’s a good afternoon removing parts, cleaning up corrosion, conformal coating and replacing parts.

If you’d like to send it to me, following are the instructions and shipping form:

Http://chrishiblerpinball.com/contact

I’m a bit backed up. But I can take care of it.

—
Chris Hibler - CARGPB #31 http://chrishiblerpinball.com/contact
http://www.PinWiki.com/ - The new place for pinball repair info