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drmcnutt · Feb 13, 2005, 02:47 AM

Been working exclusively of my Powerbook the last few months after a long move. My G4 hasn't been powered on since the move in November. I recently tried to power it up and nothing happens. Any suggestions?

I have attempted to use the motherboard reset. I pulled the battery out of the motherboard and made sure it was in properly. I think everything is okay since the move, I don't think anything happened to it on transit. I do have a processor upgrade installed, but I can't even get a whimper out of it.

Thanks for any help, I looked through the search function, but couldn't find a case that's similar.

Macola · Feb 13, 2005, 11:59 AM

I had this happen a while ago with a used GigE model, and ended up gettig the logic board repaired. Apple has a list of troubleshooting procedures that may help identify the problem:

http://docs.info.apple.com/article.html?artnum=95038

Detrius · Feb 13, 2005, 05:55 PM

Originally posted by Macola:
I had this happen a while ago with a used GigE model, and ended up gettig the logic board repaired. Apple has a list of troubleshooting procedures that may help identify the problem:

http://docs.info.apple.com/article.html?artnum=95038

They didn't mention reseating the processor.

You can check for ANY voltage on ANY of the pins of the power supply to see if it's good. When the power supply is plugged up to nothing but AC, there should be one pin that is live--usually 5V.

drmcnutt · Feb 13, 2005, 07:26 PM

Originally posted by Detrius:
They didn't mention reseating the processor.

You can check for ANY voltage on ANY of the pins of the power supply to see if it's good. When the power supply is plugged up to nothing but AC, there should be one pin that is live--usually 5V.

So I should check the processor? Reseat it?

Thanks for the responses.

Is memory a possible problem to look for? I gave a friend a stick out of it when it was in storage as a trade, but I took it from the top slot. I think this was okay, but I forgot to mention it.

If the logic board is shot I may just buy another system off Ebay since the proc upgrade is less than a year old.

Detrius · Feb 15, 2005, 06:33 PM

Originally posted by drmcnutt:
So I should check the processor? Reseat it?

Thanks for the responses.

Is memory a possible problem to look for? I gave a friend a stick out of it when it was in storage as a trade, but I took it from the top slot. I think this was okay, but I forgot to mention it.

If the logic board is shot I may just buy another system off Ebay since the proc upgrade is less than a year old.

It's worth a shot. Statistically, it's rare that this fixes the problem, but it does happen, so it's worth trying.

BTW, precisely what do you mean by "I power it up and nothing happens?" You hit the power button... does it light up? Do any fans spin? Any sound?

drmcnutt · Feb 15, 2005, 08:09 PM

Originally posted by Detrius:
It's worth a shot. Statistically, it's rare that this fixes the problem, but it does happen, so it's worth trying.

BTW, precisely what do you mean by "I power it up and nothing happens?" You hit the power button... does it light up? Do any fans spin? Any sound?

Not a thing happens. No lights, no sounds, nothing. I've had it plugged in the last few days and that hasn't affected it. Right now it is making the best imitation of a doorstop. This weekend I will try to look at the things suggested.

Again thank you for your help and suggestions.

Detrius · Feb 15, 2005, 08:55 PM

Originally posted by drmcnutt:
Not a thing happens. No lights, no sounds, nothing. I've had it plugged in the last few days and that hasn't affected it. Right now it is making the best imitation of a doorstop. This weekend I will try to look at the things suggested.

Again thank you for your help and suggestions.

In your case, check the power supply for voltage first. Next, if you can, swap out the processor and see if that makes a difference. If not, unplug everything from the logic board except what you must have to either here a beep or see a picture (not necessarily at the same time) and try again. There's a freaking tiny possibility that the problem could be the front panel board, but I've never had that problem (the other guy I used to work with did, though). More than likely, it's one of these in this order: power supply, logic board, cpu.

drmcnutt · Feb 16, 2005, 09:32 PM

Originally posted by Detrius:
In your case, check the power supply for voltage first. Next, if you can, swap out the processor and see if that makes a difference. If not, unplug everything from the logic board except what you must have to either here a beep or see a picture (not necessarily at the same time) and try again. There's a freaking tiny possibility that the problem could be the front panel board, but I've never had that problem (the other guy I used to work with did, though). More than likely, it's one of these in this order: power supply, logic board, cpu.

Yeah, I'm leaning toward the power supply. I haven't Googled for a replacement yet, is there a good place to look?

I did do some of the things suggested here, but I need to check the power supply for voltage next.

Thanks again for your replies.

Macola · Feb 17, 2005, 12:12 PM

Originally posted by drmcnutt:
Yeah, I'm leaning toward the power supply. I haven't Googled for a replacement yet, is there a good place to look?

I've used these guys both for logic board repairs and power supply purchases:

http://www.galaxyhp.com/PMG4/pwr_pmg4xs.html

Edit: They have a free diagnostic, so if you suspect a logic board problem, give them a try.

Captain Curt · Feb 19, 2005, 03:35 PM

I'm not familiar with your particular mac but I would suggest you check to see if you have a 110/220 voltage switch on the outside of your mac. If you do, you may want to push the switch to 220 and then back again to 110 to get a good reset. It's a long shot but hey you never know.

jmiddel · Feb 28, 2005, 11:22 PM

I have a somewhat similar problem, only that I do get fan and logic board light activity. The front switch lights up as long as I press it, then fades out, only the above work. If I press the switch again to turn off, it lights up again and shuts off. No startup chime. I have tried all of the above tests, including new power suppply and cpu. It would seem to be the logic board, but because there is some activity, differently than the case of the original poster, I just want to double check here before I take it out and send it in.

Quicksilver 733 (not digital audio)