That game has no posted documentation on IPDB (ipdb.org); but it does say that it’s a Whitestar game.

Do you have a manual? Does it have schematics? Is there anywhere else in the game with a fuse list describing F23? And what attaches to J3?

520-5055 is the Display Board.

Lord of the Rings is also Whitestar. On that game, the F23 fuse is “5v DC logic”. F22 is 18v controlled lamps.

Smells like a short to me.

While the game is different, the board schematics should be the same.
https://www.ipdb.org/files/4858/Stern_2003_The_Lord_of_the_Rings_English_Manual_complete.pdf

I’m concerned that J3 might be wrong.

Page 127 for the display board.
Page 131 for the i/o board, which includes various forms of power supplies.

L204 not being lit makes sense if your 5v is blown and/or shorted somewhere.

If you leave your display board disconnected, does the 5v rail light up? Does L204 blink?

Pinwiki is super handy - when it’s working properly.

https://www.pinwiki.com/wiki/index.php?title=Sega/Stern_White_Star_Repair

4.3.2 Game Resets with DMD Controller Board Connected
This may be a bit of an anomaly, but it is worth mentioning. If when the DMD controller board is connected without the data line ribbon cables, and the game continues to reset, replacement of BRDG21 may be required.

In one particular instance, a game was resetting continually with only the +5v / ground connection connected to the DMD controller board. If the board was not connected, the driver board would output ~+5VDC. If the DMD controller board was connected, the driver board's logic line would dip down to around +4.85VDC. Logically speaking, this type of symptom somewhat points to the DMD controller board having issue. However, the end result was replacement of BRDG21 per Stern tech support.

It is worth mentioning that the bridge rectifier did test correctly (using a DMM in diode test) both in circuit and out of circuit, but these tests were conducted while the bridge was not under load.

Just to point out the obvious: Make sure your ribbon cables aren’t connected “off by one”; and make sure that pin 1 on the MPU board goes to pin 1 on the video board. Ditto, video board to the plasma display.

Looking at the schematics I can’t tell where J3 actually *goes*.

Hmm Interesting. BTW schematics for TSPP are much better. https://www.ipdb.org/search.pl?any=Simpsons&search=Search+Database&searchtype=quick#4674

FRom that, I saw this:

PNG image (resized).png

Other things I’d check:

Unplugged, that J3’s cable is giving you +5v. And that it’s not accidentally reversed.

On the J3 connector of the video board, unplugged, make sure it doesn’t look like a dead short with the ohm meter. Try both polarities in case there’s a diode protecting things somewhere.

Powered off, and connected, make sure that the 5v pin doesn’t look like a dead short. Same as before.

If you have anyone nearby with another Whitestar game, see if they’ll loan you their dmd driver board.

And .. *please* put a manual in that game. Even if you keep this, you’ll want it in case someone else has to service it. the TSPP schematics are somewhat helpful, but lack all the mechanical and game specific bits.

FYI - https://www.marcospecialties.com/pinball-parts/780-5087-00 . Third edition differences appear to be in art and finish, but otherwise not materially different. eBay may occasionally have it cheaper.

I’m just glad this didn’t do any real damage. If it’s just that plug swapped, it should have been a clean short affecting only the voltage regulator on the io board, and not any of the chips that would *normally* be powered.

Hot glue, I always cut with a razor blade before removing the connector. It’s completely reasonable to hot glue things, especially in a big box of vibrating parts.

Pick up that manual. It’ll save you. It’ll save whoever does a service call (if needed) for you. And it’ll stop an awkward phone call from whoever you send this to next in the game’s life.