Working on the Data East Jurassic Park pinball (1993) and the DMD is not lighting up. Didn't look too much into it as I thought maybe the display just went out.
So I wanted a ColorDMD anyways and bought and installed one. Did not fix the issue. Now that I have a ColorDMD I can see that it powers up in the test/ info modes. Shows nothing, just like the original display in regular play mode.

I tried swapping the long ribbon cable from a known working Lethal Weapon 3 machine. Display still out.

Maybe it's the DMD controller board that is on the backside of the DMD?
Can I try a DMD controller board from a Lethal Weapon 3 or Last Action Hero? Or will that mess things up?

Tried swapping in display/ speaker unit from a Lethal Weapon 3 to see if it would display anything and it was still dead.

Reflowing header CN2 (+5V & GND) and also there was some rust or corrosion on the wire side of it. Probably why the Lethal Weapon 3 one didn't do anything.
That helped figure it out. Thanks.

Now to figure out why the top half of the backglass does not light up.

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