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Happy Ending 

I noticed that the 5 PAL chips get pretty warm. No other chips do. Edit; Replaced the Video ROM and all is good now

So as I said, I didn't have a connection from C2 to UB10 or UB11 on the 12v line. Once I connected it I get a simasimac with normal chime That means there is a non connection to the ROM, correct? or was it the RAM? or both?

The one I have is from crest. It holds 3.25 gallon of fluid and costs $1150. Not sure if that is the kind of money you are looking to spend

Here is an update, I now have 12v at C2 and on the other side of the board at C25.No 12v at the UB11 pin 11 and 12. I can run a jumper from C25 to UB11 pin 11. and the board will boot to a SIMASIMAC screen and start up bong. Somehow the schematics do not correlate to the components on the...

So I should be getting 12v+ on C2 but I do not. .42v.

I think I found something. For some reason I don't have connectivity from C2 to pin 11 and 12 of UB11 which is the 12v+ input of the sound chip.

I don't have one of those, but I can connect the board to my bench supply tomorrow. or better later, it's tomorrow already.

I don't have access to the logic board while it is on the power connector. If the line by the C2 capacitor has an issue it's either shorted to ground or OL

No short to ground on pin 5 of UB11. Do you mean the power and video connector J12? I think that line you're talking about goes from pin5 on UB11 to pin 40 on UE10. There is no short to ground. not OL between the two 

Im not sure , what through hole resistor you are talking about? 

I tested another Logic board in the same computer and it works. So I doubt it is the analog board.

Yes, to both... the supply works I tested in on another SE/30 logic board and it works fine . The logic board is recapped and cleaned in the ultrasonic cleaner

Seriously , It doesn't even make a bong or beep. just black. any ideas?

and here is the result

I think I found it Pin 5 on the ls166 (vid3) to UC7 pin 23 is OL. Pin 5 to via on the ls266 is OL. via to pin 23 on UC7 is .3ohm a closer look reveals that the pad is disconnected from the Via thank you for the help  techknight

The LS166 is new. I am not 100% sure anymore if I changed out the VRAM. I'll check the UE8 traces again.

I noticed that there is a slight difference between the OP's screen output vs mine. My lines seem to go through the mouse icon and the question mark disk.

any more or other suggestions?

I swapped the PAL (all of them) and cleaned the pins, I swapped the  PAL sockets, I swapped all the 8 bit shift registers, I swapped the ROM SIM socket and I swapped the memory SIM sockets. I replaced the capacitors and some of the resistors underneath the PAL chips.