View Full Version : One dead iMac G3 - WHY?!

Apr 14, 2005, 03:24 AM
I have a bondi blue iMac G3 233MHz/B and it seems to have 'died'. When I push the button to switch it on, it starts to boot up but just as the button turns from orange to green and the oint where the screen would normally light up, it conks out. After that, if I try to switch it on again, nothing happens. I have to leave it for an hour or so before it'll just do the same thing. Someone suggested it might be the Lythium battery so replaced that but it hasn't worked. Now someone else thinks it might be the power supply unit - an expensive item to buy if that's not the problem! Can anyone shed anymore light on this? :confused:

Apr 14, 2005, 03:28 AM
does it make any beeps as it does this?

Apr 14, 2005, 04:13 AM
No beeps, it just dies. :(

Apr 14, 2005, 04:23 AM
This could be the analogue card - the bit that translates stuff the the screen. This common failure on the original iMacs is expensive to replace. Hopefully you have backed up your data.

What version of macos are you using? 8, 9 or X ?

Apr 14, 2005, 04:37 AM
No - I have lots of things on it that I hope I can recover. Is it possible, do you think? Can the memory be transfered to a similar computer so that data can be burned onto disk?

Apr 14, 2005, 04:40 AM
Am running Mac OS 9

Apr 14, 2005, 04:57 AM
I'm also remembering there used to be a problem with the power switch on the iMac - have you tried the 'on' button on the keyboard?

Apr 14, 2005, 05:06 AM
Yup - tried that and that doesn't work either

Apr 14, 2005, 05:38 AM
It does sound like the power supply. If you know someone with an iMac then you could put your hard disk in that to get your data off. But it doesn't sound good for the iMac itself.

Sadly there is a lesson to be learnt here.

Back up your data.


These pages may be of help to you too.

Good luck and hopefully you will stick around

Apr 14, 2005, 07:01 AM
This is a problem with the flyback transformer that is known to fail in the older iMacs in time.
You probably experiance something simiar to http://www.digitalconnection.com/products/video/kdmfhdmi.asp

"After about ten seconds the power button light turns to green and immediately the computer turns off (probably accompanied by a “zap” sound from within). Typically the computer will not even begin to power up again unless you have let it sit for a while, at which point the same thing happens when you try to start it up again. If you open up the underside and disconnect the video cable, the computer will boot and operate normally (assuming nothing else it wrong with it) and you can actually use the iMac with an external monitor."

You may want to try opening the underside and disconnecting the internal monitor just to see if it works. It uses the same technology as teh old DB-15 apple displays. Just be careful around CRTs. They have the power to kill -- even after being unplugged for years. Source of information:

Apr 14, 2005, 10:51 AM
I have a iMac G3 500 DV SE and the same sort of thing happend. I would hit the power button it would turn green, no display at all would come up then it would switch off. When i took it in for repair (at the time the only local repair shop was CompUSA) they wanted to blame first the logi board/video bard, then the display, then after all that they replaced the power supply and all worked well. What it seemed like to me was the power supple went out and idnt have sufcient output to power up the whole unit so it just shuts down. Luckily at the time i still had apple care on the iMac, but im sure replacing a power supply is cheaper than buying a new system :) Check ebay i would bet people are selling them for cheaper than apple will sell it to you for. Also be carefull around the CRT, they hold a lot of power even when there is no current runing through it, either discharge the CRT or be really carefull around it :) good luck!


Apr 14, 2005, 06:35 PM
I saw this exact problem on a lot of iMac's, weather it was the original Bondi, the 5 flavore, or any of the slot loading iMac's. The difference is, on the Bondi iMac's the Analog board and Power Supply were two completly different boards. On you Bondi this is most likely what is wrong, I believe it was about a 150 - 200 dollar repair back in '03, not sure what it is now. I'd call your local Apple store and see what replacing the Analog board would cost. Might not be too much now. They might have a used one as well, I know we used to strip old machines that people gave to us to be trashed and used the parts we were able to pull.

EDIT: I would not recomend replacing the analog board yourself unless you know how to discharge the CRT, or have the complete take apart for the Bondi iMac which will tell you how to do it.