Power Mac G4 (mirrored door) totally dead--power supply?

[4seasonphoto]

Anyone experience this? No signs of life whatsoever: No fans spin up, no relay clicking, no noises, no nothing. Nothing obviously blown on the motherboard, no bad smells of burnt electronics. Tried a new battery but that made no diff. Wondering if a fuse in the power supply has failed, but it looks like kind of a pain to get in there and take a look. It's one of the company giveaway machines, but I think if I don't fix it, it'll likely wind up as a throwaway, and we can't have that can we.

 

[MacMan]

Have you tried a CUDA reset? Look for the little button on the motherboard and give it a push for a few seconds. I've had to do this with G4s before and it sometimes works, my G4 needs it pretty much every time after the power has been unexpectedly cut off.

 

[Quadraman]

I'll take it as is if you want to get rid of it for cost of shipping.

 

[4seasonphoto]

Have you tried a CUDA reset?

Yes thanks, I did try that, but to no avail.

 

[4seasonphoto]

I'll take it as is if you want to get rid of it for cost of shipping.

Maybe! Can you issue a UPS call tag or something similar?

 

[Quadraman]

I'll take it as is if you want to get rid of it for cost of shipping.

Maybe! Can you issue a UPS call tag or something similar?

I don't have a UPS account.

 

[4seasonphoto]

I don't have a UPS account.

If it's anything like FedEx, it's real easy (and free) to do this.

 

[Quadraman]

You couldn't get the money from me first and send it yourself?

 

[Bolle]

just take the PRAM batt out and leave it unplugged over night. one of my dads MDDs acted the same way as yours and not even a CUDA reset did the job. the battery trick finally did put it back to live.

 

[4seasonphoto]

Thanks Bolle, I'll try that next time!

I found a taker for the machine locally, and I think it's in pretty good hands now.

I don't accept payments for shipping because I don't want to run charges through the company's own FedEx account. Even if it's reimbursed, they account for every penny and that makes more work. By call-tagging it, we avoid that. I also need to avoid even the appearance of profiteering from the company's goodwill.

 

[spuntotheratboy]

just take the PRAM batt out and leave it unplugged over night. one of my dads MDDs acted the same way as yours and not even a CUDA reset did the job. the battery trick finally did put it back to live.

I've just taken my PMU battery out, waiting till tomorrow to see if it helps...

This has just happened to me too on a G4 'digital audio', except that after a PMU reset (which I did very carefully by the book) I've noticed a clicking noise from the power supply whenever the power is plugged in.

But there is still absolutely no other sign of life, not even the power button light coming on while I press it. Moreover, the monitor completely died, in a similarly absolute way, at exactly same time! That seems to be the oddest thing about it. The fuses for the cpu and monitor are both fine.

I can't say exactly what was happening when it happened because i was out at the time and my 11 year old daughter was using the machine. She reported that the power light on the front was flashing, although it wasn't by the time I saw it.

So, although I'm hoping for a result from Bolle's battery trick, I'm kinda guessing it's not going to work... does anyone have any idea what the next step is? Short of hiring someone to fix it? A new power supply, for instance?

[xx(] ]'>

Thanks in advance,

Ben

 

[equill]

You appreciate that, kind advice notwithstanding, 'tain't a CUDA in G4 towers but a PMU, so treating it as a CUDA just flattens the battery overnight. Your clicky, clicky, flashy sounds just like a failure of TRKL in the power supply. It's either deep delving and surgery for you or a new PSU. Before desponding, measure the output voltages from the PSU at the MLB connector and compare them with spec.

de

 

[spuntotheratboy]

Thanks a lot for your help.

This morning, however, the situation has resolved somewhat. The machine will boot as long as the monitor is not plugged in! At least it sounds like it's booting up properly, I get the chime and all the other noises I'd expect, but of course I can't actually see what's happening. And the clicking from the power supply seems to have vanished.

With the monitor plugged in, nothing. Not the least sound or light when I press the power button.

I don't know if taking out the battery overnight and resetting the PMU (yes, not CUDA, my error, sorry) had anything to do with it, but at least at the moment it seems as though the problem is either in the monitor or the graphics card...

So my next plan is to a) plug the monitor into another ADC-compatible machine and B) borrow a VGA monitor to plug into the other connector on my machine...

Then it looks like either a new monitor or a new graphics card, or maybe both since ADC isn't widely manufactured these days.

Thanks again, I really appreciate that people are prepared to help out in an emergency!

[] ]'>

Cheers,

Ben