Wisconsin Pinball

I have an SF2 that has an intermittent problem where I get Chun Li jackpots (an opto on the top-left habitrail... I think it's SW91?) when other things happen. I haven't nailed down all of the things that make it happen, but I've seen:

* On plunge
* When hitting the Dhalsim hole (huhuhuh)
* When pressing the left flipper button

These are all intermittent, and while the first two are in the general vicinity of the Chun Li jackpot opto (vibration?), the flipper sure ain't, and it's the most repeatable method. I haven't figured out what makes the issue occur or not occur. The Chun Li opto works just fine on its own. I went through switch matrix test and see no anomalies. I read that the lamp matrix on Sys3's can cause switch matrix problems, but I see no lamp matrix problems, either. I did the ground mod on the table already. I'm generally baffled.

Does anybody have any tips on likely culprits?

If the switch tests check out okay and you cant get any false switch readings, i would look at the controlled lamps next. on system 3, they share the strobes with the switches. i would look at your manual and see which controlled lamps share the strobe as that switch, and then start taking the bulbs out one at a time and see if you can eliminate the issue.

do you have a manual? if so can you upload a pic of the switch strobes and the lamp strobes?

I didn't see any spurious results from the tests... I had the left flipper tripping the jackpot every time, and quick jumped into the switch test. The switch test looked normal.

If I disconnected the entire lamp matrix at the connector, would that effectively "remove" all the bulbs for the sake of this switch/lamp matrix cross-connection issue? That would be a handy first step to quickly check if so.

I attached the switch and lamp matrix photos.

Thanks for the help!

are you using LEDs in the flashers?

I had a previous GTB where that cause issues with optos.

Oh! I am in a few, actually. There's a couple spots where I wanted eyeball nuking brightness. I can swap those out quick tonight and see if that helps.

Can you post the two pages that have the playfield showing switch locations and lamp locations?

Here they are. The Chun Li opto is in the upper left corner, inside the habitrail for the left inlane return.

I pulled most of the LED flashers tonight, and I didn't get any spurious jackpots until my fifth game, which is much longer than usual. There are a few more flashers that are really deep in the table that I'm not going to be able to get to until tomorrow. I'll try those too and see if that fixes it completely.

I did get a Vega victory (which is a standard rollover) when I wasn't supposed to, but that's a new one to me, so I'm going to go after Chun Li first.

So, I thought I had fixed this a few months ago with an opto cleaning. It came back a couple weeks later. Then I thought I fixed it again with the ground mod, but it came back again shortly thereafter. This morning I changed out the remaining flashers, and the game seems rock solid! I'm pretty gun-shy of calling it fixed given how this thing seems to keep rising from the dead on me, but I'm cautiously optimistic!

Thanks for the help! I hope I'm not back here in a month or two announcing the return of this problem, but for now I'm pretty excited to have SF2 back in the lineup! Unlimited free points made it a bit tough to play versus people.

This forum rocks. I thought about posting on Pinside, but wasn't looking forward to the snarky SF2-targeting "douse it with gasoline" comments. Wisconsin Pinball has "all the techs, none of the trolls".

Good to hear.... thanks for posting the manual portions, it will help a ton if you still experience issues.

Yeah, I know the Gottlieb manuals are "not for posting", so fair use snippets it is.

You can post individual pages without issue. A few years ago I was working with a few guys on a Gottlieb System 3 repair guide, and Steve Young was very nice and supportive, and didn't have an issue posting portions of a manual (obviously not the full manual though).

Good to know. That's reasonable. I like having paper manuals when possible, cause reading schematics in a PDF is pretty rough on a laptop.

glad to hear this is fixed (fo now )

Yeah, I was useful for a tech post (finally!)

Hopefully it holds steady...