Anyone have any troubleshooting ideas for a CPU led code 7 on my Space Shuttle? The Marvin guide hints at "the dreaded black and white connectors" being swapped- I'm not sure what that's referring to, but this machine has worked 100% for months then just quit on me. I did notice about a week ago that it wouldn't turn off with the switch, but it didn't happen again- then this week, all of a sudden nothing, other than the 7 on the CPU. It's a restored machine, among other things with an updated power supply, and I confirmed I have the 5 and 15 volts on the power supply heading to the CPU. Great pin and my kids are ticked that it's not working ( and so am I).

Well, that's what I get for overthinking my search query- shouldn't have said "led" or "CPU". Several good posts on several sorcerers with an error 7- sounds like it's either u20, one or two other ICs, and/or cold solder joints, probably from my basement which I thought was warmer than what it should be for my pins. I'll try a couple of things and write back how it goes, thanks for the suggestions, everyone. I think either you or Collin said it, ranhorton- the vast majority of the time in my troubleshooting my pins, it's Occam's razor, something simple- only with barn sitting machines do you get the really squirrelly issues( or a HH that had caught on fire, that was a fun repair).

Finally got a chance today to take a look- no sound when I hit the sound diagnostic, so that's good, but zero VDC on pin 20 of U17. I took out the game rom at U20, for what it's worth, still get a 7. I'm going to try the additional logic probe steps in the sys 9 guide to see if I can determine if it's a bad U17 or a bad u20( before I look for the weird problem ranhorton had).

I did notice ( shame on me) that one of my batteries had started to corrode, but it hadn't got far, luckily, nor have I read where this would make the error 7 code. For reference, my pinbot had a completely destroyed battery holder, but never gave me a 7.

Replaced u17, no change- time for a new game prom, it looks like, I'll try that next.