iMac G5 electrical problem

[Tearose]

Sometimes it just turns off without warning. I've checked for a loose plug, but that's not it. It's very random- sometimes I'll be doing something when it turns off, sometimes I'm just reading something on the screen. It does it several times a week, sometimes a couple times in a day. When it happens, I press the start button and it starts right up every time. Does anyone know what might cause this and where in the computer I need to look for it?
Jill

 

[jmgalvin]

See if resetting the System Management Unit helps

http://docs.info.apple.com/article.html?artnum=301733

Using OSX 10.3.9 on a G4 & G5

 

[jmgalvin]

You might also have to reset PRAM. Hold down Command-Option-P-R keys while starting up until you hear the chime a second time.

Using OSX 10.3.9 on a G4 & G5

 

[Tearose]

I have finally had the oppurtunity to see if doing either of those works. No, they don't. It stayed on a long time- over a week, but then quit twice yesterday, and again this morning. Any other ideas? Thanks for trying,
Jill

 

[jmgalvin]

You might have a faulty power supply. This has been identified on some imacs by Apple and, if applicable to your machine, might include free repair even if out of warranty.

Here is the applicable page from Apple

http://www.apple.com/support/imac/powersupply/repairextension/

If possible it would be best to schedule an appointment at the genius bar at the local Apple store, if there's one near you.

There is another imac repair program for another fault, but it does not seem like the one you have. Here's the page for that

http://www.apple.com/support/imac/repairextensionprogram/

Using OSX 10.3.9 on a G4 & G5

 

[Tearose]

A faulty power supply seems likely, but unfortunately, mine isn't covered by the repair program. And their nearest store is a half hour drive away. I wonder if there's a way to test it. Sometimes it can stay on for a week or more, then shut off several times in a couple days.
Jill

 

[jmgalvin]

AS far as I know, there is no real test for the problem. You might try resetting power management again and resetting PRAM as im my first answer.

Intermittent problems are always the most annoying because their so hard to diagnose.

Using OSX 10.3.9 on a G4 & G5