Display wasn't working in a STTNG, moved the DMD, display controller board, and ribbons over to another WPC game and all works fine.

Voltages were fine in STTNG, although 12V was low (8.5V), but I wired 12V to the display directly from another source and it didn't fix it.

My next guess would be issue on CPU board, but my WPC schematics don't show me data bus to display, not sure what chips are involved. I suppose it's possible it was just a bad ribbon cable connection on one of the boards in STTNG, but I cycled most of those connectors during troubleshooting.

Thoughts?

Thanks!

Haven't worked on this one in a while, still want to try the CPU board from the STTNG in the other game. Maybe the ASIC chips needs to be reseated?

Yes, 12VDC from driver board.

All voltages to DMD were fine, at the DMD connector, except 12V was low (created at DMD controller board). However, DMD and DMD controller board worked fine in another pin, still with the low 12V.

No flicker

Wow, this thread really got hijacked. Now back to originally scheduled programming.

UPDATE;

Replaced the 12V Zener on the DMD controller board and installed tested CPU board, DMD controller board, and DMD. It worked fine for about 5 minutes, then the display stopped working. Swapped the power driver board and it did not improve the scenario. Do see some dots flicker when powered on, if it's been left off for a while.

Voltages to DMD are now fine (12V was previously low). Ground is good. Ribbon cables are good. All boards work in other machines. Only other issue I found was a bad fuse (F116-12V) on the power driver board, but replacing it did not fix the display.

Yikes!

Ok, some more interesting phenomena...

Another DMD (Dale) was installed in the ST:TNG, and it worked. However, the ST:TNG DMD (Cherry?) still doesn't work, but it works in other games (T2 and TZ).

Any ideas why a DMD would work in one game and not another, when a different DMD works in all the games?