PowerMac G4 won't boot

jfpoole · Feb 6th, 2003, 05:57 PM

We've got a dual 1GHz PowerMac G4 here that won't power up at all. Pressing the power button causes it to light up, but as soon as it is released it goes dark again. Nothing spins up. I suspect the power supply has gone south, but I thought I'd make sure this wasn't an easily-solved problem first.

Any ideas?

monokitty · Feb 6th, 2003, 07:37 PM

The seconds it does power on (light turns on) do any fans start to spin? If not, I would highly suspect a bad power supply. If the fans do go up, I hate to say it, but I'm thinking a damaged logic board - which would be a pain to fix/replace at a heavy cost.

jfpoole · Feb 6th, 2003, 08:29 PM

Lars wrote:
The seconds it does power on (light turns on) do any fans start to spin?

Nothing spins up, which lead me to believe that the power supply is kaput. Luckily the machine is still under warranty, but it's going to be a pain to ship the machine away....

monokitty · Feb 6th, 2003, 09:47 PM

<BLOCKQUOTE>quote:</font><HR>Originally posted by jfpoole:
Lars wrote:
The seconds it does power on (light turns on) do any fans start to spin?

Nothing spins up, which lead me to believe that the power supply is kaput. Luckily the machine is still under warranty, but it's going to be a pain to ship the machine away....<HR></BLOCKQUOTE>

Hmm... weird, because it sounds like the power supply is toast, but if a light goes on, even for just a second, it means there's power - the power light does get its energy from the computer's power box, I do believe...

jfpoole · Feb 6th, 2003, 09:54 PM

Lars wrote:
Hmm... weird, because it sounds like the power supply is toast, but if a light goes on, even for just a second, it means there's power - the power light does get its energy from the computer's power box, I do believe...

It does, but the light runs on a different voltage, so part of the power supply could be toast (i.e., the bits that supply higher voltages to the motherboard and the hard drives), but other parts could be okay.

It's a very confusing problem.

monokitty · Feb 6th, 2003, 10:09 PM

Confusing situation indeed... bits and pieces of the power box toast - now that would be a pain. Since your machine is under warranty, I would have it checked out and repaired. It may take the machine away from you for a while, but on the bright side, you're getting free repairs and are just delaying the return time of it by keeping the check-up off.

jfpoole · Feb 7th, 2003, 01:15 AM

pras wrote:
I think the KBase article is no. 95037

Thanks. I'll give this a try tomorrow morning. If that doesn't work, then we'll ship it off to Apple and see what they can do with it.

pras · Feb 7th, 2003, 12:07 PM

<BLOCKQUOTE>quote:</font><HR>Originally posted by jfpoole:
We've got a dual 1GHz PowerMac G4 here that won't power up at all. Pressing the power button causes it to light up, but as soon as it is released it goes dark again. Nothing spins up. I suspect the power supply has gone south, but I thought I'd make sure this wasn't an easily-solved problem first.

Any ideas?<HR></BLOCKQUOTE>

Two things you can try:
1. Make sure no USB peripherials (except keyboard and mouse) are attached when starting up. Once up and running attach items one at a time, etc.

2. Read Apple KBase article at http://docs.info.apple.com/article.h...chMode=Assiste d&kbhost=kbase.info.apple.com&showButton=false&ran domValue=100&showSurvey=false&sessionID=anonymous| 160421355

If the machine is new, you don't really need to worry about the battery, so just hit the switch once, as per instructions.

Hope one of these works for you.

pras · Feb 7th, 2003, 12:12 PM

I think the KBase article is no. 95037

gordguide · Feb 7th, 2003, 01:42 PM

Apple has had problems with the sub-board at the front of the computer behind the power switch. The issue affected Graphite G4's made on or about fall 2000. This sounds identical.