I have an Earthshaker with no working display. Being unsure if it is the display itself or something else, I performed some measurements and discovered two things I need help with:

1. Connector J2 on the Power Supply board powers the display and should have +5V, +100V and -100V DC.
I get +4.91V, +99V, -128V DC when display is disconnected. However, when display is connected, the +99V changes to +32V! The other values stay unchanged. Also not sure if -128V is out of accepted range.

2. On the CPU board, display connected, connectors 1J1 and 1J3 (goes to display) has most of their pins measured 4.9V. However, there are a few pins that measures 0.3V on 1J1 and 1.15V, 3.36V and 1.91V on 1J3. Not sure if this is right?

Any ideas where to go from here? Why do the +100V drop when display is connected? And why do some pins measure diffrently than the others on 1J1 / 1J3? It would be GREAT if someone who has an Earthshaker could perform same measurements.

I have measured lots of stuff on the CPU board and Power supply, everything else seems fine. Even changed the ribbon cable that goes to the display (not the one that goes to audio board).

I THINK that game is playing fine, only display is not working. Lost the free-play settings, so I can´t verify the games functionality as it is right now. Need to fix display first!

Thanks! Located two transistors Q1 and Q3 that do have continuty between two of their legs, suppose there are shorted, right?

Well that should hopefuly fix the -128V issue.

How about the +99V dropping to +32V when the display is connected, will that issue be fixed as well or is it the display board that is causing this?

Thanks, will start with the Q1 and Q3 replacement on the power supply, but I doubt they will fix the +100V drop. Worth a try...

Could it be the caps on the power supply that causes +100V drop perhaps? Maybe I should replace all the caps? Hm...