Herg, good observation. There is a cap in parallel to R91. Actually, this reminds me of the similar failure that movie theater in SD saw back in May...

https://pinside.com/pinball/forum/topic/does-anyone-know-about-the-wozle-that-supposedly-burned-in-s-dakota#post-2462239

Looking at the photo Lloyd posted, it's clearly the exact same problem. Failure of Q20 and the choke coil. And once more, R88 has gone open by melting itself off the pads. I wonder if it's part of a feedback circuit for Q20. Maybe this caused Q20 to overheat, short, and fry the choke? However, it doesn't appear that R91 has a cap in the operator's photo.

image.jpeg

Does JJP have an approximate date range for this failure?

I know, but it's good to observe as many details as possible. Now we know R91 is most likely not a factor. Do you know if lamps use part of the 12v circuit to operate?

Do you know if this affects all power supplies prior to the new design?

For reference...

Old: 15-0015-00,REV3 11/5/2013
New: 15-0015-00,REV2 3/10/2015

That's quite a large time span. Here's another case that happened just 3 months ago.

https://pinside.com/pinball/forum/topic/woz-burning-smell-inductor-coil-very-hot-help-please

Does anyone have a scan or photo of pages D142 and D143 of the print manual? I would like to know what is causing this and what to look for if you have a REV3 Unified Power Source Board.

What is your manufacture date?

I know it was yours, summarizing dates. The D section doesn't go beyond around page 70 in the PDF copy I found on their support site. Am I missing something?

Thanks. I thought I read somewhere that schematics were only available in the print version.

I read somewhere you have to have a bad board, but I'm sure that's negotiable if you can confirm you have a problematic version.

I would say you're fine. See if you can peel the number label off the part label and see what revision your board is.

I was wondering the same thing. Maybe they are falling back on an old design?

If that's true, why does this section of the board appear to be 12v?

Sorry Herg, I was actually replying to CactusJack.

I'm sure it's because Jack is too proud of his system. They had no trouble giving us a full color 100+ page illustrated manual.

Is that a transformer or just a choke? I can't tell if there is a winding underneath or a ceramic insulator.

That's crazy. I would assume since the "newer" inductor we have seen is bigger with more wire it would dissipate more heat.

Hmm, seems like the larger inductor isn't exclusive to the REV2 boards.

I really wish we could find some info on the original choke.

So now we have to entertain the idea of the inductor failing under normal conditions, regardless of the two switching regulators. On every photo of catastrophic failure I've seen at least one of the regulators as literally fried or exploded. Did the heat from the coil cause this, or vice-versa? I don't fully understand the conditions if one regulator fails, but I would assume it would be working quite a bit overtime to compensate?

Great observation louvnj. L9 is what danisme said in his thread.

Now that I think of it during the big LED craze JJP had technicians replace the LED power supplies on some games. If this board powers the new LEDs, maybe the design of the 12v circuit was a bit rushed.

Are you saying all of these things were destroyed as a result for the failure?? That's incredible! What probably happened was this:

Maybe the new boards are backward compatible with 5v. I talked with one of the engineers a year or two back and they replaced the power supplies along with the new boards because IIRC 5v wasn't enough to activate some kind of voltage regulator in the new boards that would prevent failures.

That was the LCD controller which also runs on 12v.

Speak with your wallet! Amend a threat to sell or return your game to the ticket. That should get their attention.

Pretty obvious it's a stock photo.

No need to apologize to Lloyd, he doesn't make the high up managerial decisions in the service dept. He seems to be doing what he can per usual, and that's providing excellent service to JJP's customers.

Good job raising awareness!

This is clearly getting a bit out of hand. How in the world can 80° temps cook a processor or GPU with full heatsinks, with 127° considered perfectly safe to use on a major component with no thermal transfer system? And that's just 10 minutes! What if you have a machine on location that runs for many hours a day, most of the time in attract mode? I'm certainly no electrical engineer, but I fail to see the logic.

Keep in mind, Lloyd is a volunteer support rep. For all that JJP has been doing to aggressively resolve the problem he and his crew have been doing an awesome job. I understand you're not referring to him specifically, but I can't help but imagine phones are ringing off the hook at the moment.