Got a WW a couple weeks ago and it's been rock solid, no issues. I shopped it, added LEDs a few days ago, and played several games since with no issue. Tonight I swapped a speaker and did a few other benign mods and housecleaning: looking more closely at the boards, I made sure everything was seated tight (a few connectors did seem to push in a tad), and even replaced a couple missing mounting (grounding) screws.

Now when I turn on the machine, I am greeted with GI lighting only. No controlled lamps, no sounds, the alpha display (a blue rottendog LED) is dark, buttons do nothing.

MPU board diagnostic LEDs are all dark (the board is visibly pristine with NO alkaline damage). Pressing the CPU test switch does nothing.

I have checked, rechecked, and triple-checked all connections. I even removed the missing grounding/mounting screws I added.

It seems to me that the MPU board is not getting power, hence the lack of controlled lamps. But is a dark Alpha display and lack of sound related to that, or something else?

Trying to test the power supply... I am not sure I'm doing it right? Should be simple: on the 15pin connector use pin 1 for ground, then check the +5, +12, and -12 voltages on the other pins. Right?

But the readings I get make no sense at all! (what should be 5 reads as 0; +12 is 0 while -12 shoots into 90 at first... eventually they come into 12V, but I never get 5V. It makes me think my meter is suspect but when I check known good stable parts, the meter is fine).

...so I defer to the experts here. Help please and thank you!

Thanks adalogue. Before going to bed I did just that: removed all outputs and used the test points (which I originally couldn't see well) on the PSU board. Still the same results: on the 5V rail I get 0; +12 nets 0, -12V nets... fluctuating weirdness. So at least that's "consistent".

Any ideas what would make a PSU *suddenly* die like that? FWIW it looks like a couple smaller caps and one transistor were previously replaced, and the cap at C8 is bulging. The filter cap has to be 25 years old so I'm sure it's due as well. Thing is, the game didn't seem the least bit flaky prior... and suddenly now I have *no* 5V (or 12V) output? Didn't think that was typical.

I'm hoping it's just bad luck/timing/coincidence. There are no blown fuses, there were no alarming sounds/pulses/shocks/smells/magic-smoke-releases when I turned on the machine, as you might expect if you wired or shorted something wrong to *cause* a PSU to blow or another failure. Just... a quiet death, ha ha?

I toned the fuses out and they were good. But I didn't think to take them out of the holders at the time since FWIW they don't even look the slightest bit worn.

Not a bad thought on the transformer and I'll check that tonight. But if it went bad, wouldn't the GI be out as well? Actually now that I recall the GI, the PSU test point measurements make even less sense. The test points check voltage independent of the connectors, right? What does GI run on?

Ah, that makes a little more sense. Thank you for the info and advice! I'll look into this tonight.

Oh man. This situation has revealed that I am two things: 1) An idiot, and 2) a dead one walking. I blame it on the wimmens.

See, while I was working on the speaker and stuff, happily minding my own business, a catfight erupted between my wife and pre-teen daughter in the next room. I attempted to tune this out. But they gradually drifted my way and forced my distraction and reluctant intervention...

...all while I was working, trying to focus and ignore them, when I really couldn't/shouldn't/oh-god-and-once-the-7yo-gets-older-I-am-doomed...

So anyway. As soon as I read you mention the word "transformer" I recalled: "In the heat of that argument, with me trying to mentally LA-LA-LA-LA-LA and mind my own business and pretending to be too busy to intervene, did I kinda absentmindedly distractedly look at the transformer connector and maybe disconnect it... only to be promptly, inevitably, sucked into the femstorm for good - and thus forget all about it?"

Ahem. Yeah. I forgot to plug that ONE transformer lead back in.

I mean, I *completely* forgot... as evidenced by all my desperate troubleshooting hours later once I finally got back to it. And I'd probably still have forgotten if you hadn't mentioned it. I mean, what kind of idiot unplugs the transformer to plug in a speaker???

hahahahaha

But IT IS WORKING THANK YOU!

I need a beer...