iMac G4 won't boot - I'm desperate

[s_sador]

Hey guys,

Just inherited a pristine G4 700Mhz iMac and while I was trying it out, it had booted in OS 9.2 after several times (I think I've pressed alt or something) and said something about memory issue but otherwise you could work in it.

The problem is that now it does not want to boot. There is the startup chime and the sleep light goes on but the screen stays black. It won't respond to keyboard commands (reset PRAM, open disc tray, switch start up disks) either.
There is however, a high pitched noise coming from it. That could be the fan because it's full of dust but if the disk had failed, I could have force it to boot from an external USB drive, right?

Please, any assistance will be helpful. I'm an avid collector of vintage Macs and this one is really in in mint condition. Thanks!

 

[Robert Jacobs]

Older macs usually failed to turn on when the pram battery died, but there'd be no chime in addition to a blank screen. My first thought is that it's the memory stick that's gone. The iMac G4 700 (http://www.forevermac.com/2002/01/apple-imac-g4-700mhz) had a PC133 Dimm on the motherboard (internally) and an SOdimm on the underside by the airport card- there's a sort of guide that was posted. Pull the SOdimm and then see if it'll power on. If there's no sodimm (wasn't user upgraded), then it's the internal dimm that's probably faulty and a swap out will highlight that as a possible issue.

If the memory swap doesn't fix it, then it may be on-board graphics and testing that means plugging in an external monitor to the mini dsub port. If it's not that, then it's possibly the ide controller, a failed drive (usually causes a blank screen) or worse.

However, a blank screen after frequent power on and off indicates a faulty memory stick as most likely.

 

[louishen]

I would try the PRAM battery first as that's the cheapest part and on an old G4 like that the first part that will cause a failed boot-up

There is a guide here
Official Apple Inc. repair guide for iMac G4 17" 1.25GHz - iFixit

 

[s_sador]

Thanks guys, I replaced it's ram and its working great now. However, it is a bit noisy, I think that the high pitched buzz might be coming from the hard drive as I was trying to boot it from a CD and the sound was absent. As I said, the computer was picking up dust for a few years, could this be the reason? Otherwise it is working like a dream.

 

[harryb2448]

Yes indeed it could well be the hard drive. Got any system install discs? If so boot from them and run Repair Disk.

 

[s_sador]

Yes indeed it could well be the hard drive. Got any system install discs? If so boot from them and run Repair Disk.

Did that, disk was ok but it's still whining. I'll record that sound and post it on youtube, now I'm convinced that it's the fan

 

[harryb2448]

Well it ain't pristine then. If you get it going okay you may well be disappointed in performance. That model was first released ten years ago, yes early 2002 which is like dinosaur era.

 

[s_sador]

Well it ain't pristine then. If you get it going okay you may well be disappointed in performance. That model was first released ten years ago, yes early 2002 which is like dinosaur spew

Don't worry, I got is as a gift and by pristine, I meant the casing is great, no discoloration and stuff. It simply looks as new.

Anyway, I did a little research about that whining noise, could that be the power supply?

 

[techiesteve]

Open it up and pull the hard drive power connector, then power on again. If the whine has gone it'll be a noisy hard drive. The hard drive sits between the optical drive at the PSU.

 

[dtravis7]

Open it up and pull the hard drive power connector, then power on again. If the whine has gone it'll be a noisy hard drive. The hard drive sits between the optical drive at the PSU.

Excellent Suggestion. I do that all the time to see where the noise is coming from.

 

[s_sador]

iMac G4 buzz - YouTube

here is the video, try to watch it in full HD and with headphones to really hear the buzz, I'm concerned, could this really be the power supply? I mean, to me it sounds more mechanical.

 

[s_sador]

Anyway, the issue is the hard drive - fan and power supply are ok. Thanks everyone