Hi Hotrob,

Was the machine oké when u picked it up?
4.9 Volt must be enough to start it up, did u checked all IC,s in there sockets?

Fritz.

What are the diagnostic LED's doing on the MPU board ?? If they are on or blinking there is a problem. 4.9V should be close enough for operation.

I always check the fuses first, you know, after the incident...

I would check out all the proms/eproms next.

That sounds like a fully booting board to me? (per some info previously posted in the internet)

System 11a, 11b, 11c CPU board LED's.
On system 11a, 11b, and 11c CPU boards, there are three LED's about in the middle of the CPU board. For a working game, here are what these three LED's should be doing when the game is turned on and in attract mode:

Left LED (labeled "+5 vdc"): shows that +5 vdc is present. This LED should always be on.
Middle LED (labeled "diagnostics"): should be continually flashing.
Right LED (labeled "blanking"): shows the blanking circuit is working, and should always be on.

So that appears OK. But, looking at the pic you posted, I also remembered this:

I turn my system 11 game on, and the score displays will only show 0's and X's in the middle of them.
Problem: the game thinks you have "slammed" it.

Answer: there is a slam switch inside the coin door, just above the coin door lock. This switch should be normally open. If this switch is shorted or bent closed, you will have this problem. Often people will accidentally bend this switch when putting credits on the game (a good reason to have the game set on free play!). If the switch is not shorted closed, the switch matrix could also be damaged, as the slam switch is part of the switch matrix.

From looking at your pic, I'd be all over this as a possible solution. You've obviously got some segments missing from your displays, but otherwise it appears to be the same symptom.

With chip in the board and game off - using DMM on diode setting - red lead to pin one and black lead to other pins should be reading .4-.6 volts. A short between Pin 1 and any other pin would indicate a bad chip.

With the chip out of the socket, are you getting a dead short between pins 1 and 9 of the socket itself? If so, ya, that's a problem too. If the socket itself is indeed shorted, I'd assume it took the chip with it. Not sure how to advise you on that, but if that is what is happening you do need to sort it out. Probably pull the board and inspect the socket to start with, then start buzzing out traces.

Check the under playfield fuse(s) if the flippers are not working

That's good news. You are 90% of the way there now.

Reset all the connectors just for kicks?
2 displays in that machine or 4? Try disconnecting various displays and try to boot with only one plugged in (sometimes one bad display can impact other displays)

It may go back to that issue with U51, as that chip is in the display circuit I believe.

Ah, the first game!

Did you have to do anything to the flippers, or did they just mysteriously start working?

On the displays, I assume both the upper and lower display glass is the same? (sorry, my Sys 11 has 4 smaller displays, 2 of which differ, so I am guessing a bit here). If so - to further diagnose your display problem, just switch the cables. Probably the easiest way (assuming you have the length) is to switch them at the display board itself.

By doing this, you are rerouting the "signals" from display 1 to display 2. We know the machine is sending good "signals" to display 1, so now we should be able to read the exact same information on display #2. However, if display 2 is still dead - that's a pretty good indication you have a bad display itself. However, if display 2 now works (receiving the signals from the display 1 output)....that means all of your displays are good, and you have a problem upstream in the display boards or the wiring.

On your backbox lights, I'm sorry, I don't know the exact board you are describing. But I assume those are just regular GI lights - I guess there is a good chance what you are talking about is a simple relay used to turn power on and off to those lights. The lights that don't work - are they all on the same wire string/circuit and trace back to that relay? Check the wires on both sides of that small board? Trace them back up to the backbox and check for burnt pins/connectors? (that's the most typical cause of non-working GI lights)