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iMac stopped booting 1

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siituser

Programmer
Sep 30, 2002
67
CA
Hi there,

I've read other posts with similar issues but I want to sure before I go riping his computer apart. I'm more knowledgable about the inner workings of a PC then an iMac.

I have an iMac 350 slot loading, 512 MB ram, orignal 40GB HD. I upgraded to OS X version 2 a year ago and had no problems with the upgrade or it running since.

The computer was running fine last night. This morning it was frozen, did a hard shut down and rebooted again no problem. Came back a hour later and it had frozen again. Another hard shut down but this time it doesn't come up.

When I press the power button, I get a chime, I can hear the hard drive accessing for about 2-3 seconds and then nothing. I have tried putting in the OS X cd again, it spins but nothing happens. I tried an old utilities disk and held down the C key and again nothing. I'm also seems I'm getting no power to the USB keyboard and mouse. I've swapped the mouse and keyboards ports.

I'm not familiar with zapping PRAM. not sure if that would help. Does it sound like a motherboard issue? HD? Do I have a new doorstop?

Alao, might I be able to hook this drive up to a Windows or Linux box to access the drive and get some data off of it? My wife has all her picutures on there...

 
I fixed this problem on an identical machine by changing the PRAM battery after zapping ( Restart and hold down Command-Option-P-R.  The computer will restart, continue to hold buttons until the computer has restarted several times.)
had no effect.

Paul.
 
If nothing's booting, it's not looking good. I'll give you a few hints. If you can't boot from the CD (this can take a l-o-n-g time for that boot on your machine) it doesn't look like a hard drive problem. You might try starting from the original iMac disk. If you get a start from this disk, you'll know that the motherboard isn't fried. But you won't be able to fix your HD with this because yours is now set of OSX

Isn't there a reset button on the side? We have a couple Imac 266s and there's a hole near the usb ports where you stick a straigtened paper clip if necessary. I thought Apple put a button there with later models.

Try starting the machine - from it's hard drive, but with the OSX cd in the drive - holding down the option key. This should give you a choice of startup disks. If you don't get this there's a chance that you have a motherboard problem. If you do get it try starting from either OSX on the HD, OSX on the CD, or OS 9, if that's installed. I'd try 9. If you can get a start from the CD, that would indicat that your hard drive needs repair. Lauch disk utility and repair it.

You can also try to startup in Safe mode. As soon as you hear the chime press the Shift key. Release the key when you see the progress bar.

You can try a PRAM reset by holding down the command, option, p and r keys while starting. Relkease after the second chime.

There's one nasty thing that happens and prevents starts - the CUDA switch. I don't know if your machine has one, but I've worked on a lot of macs with them. It's on the logic board - usually near the PRAM battery. Sometimes, when the battery dies, the CUDA needs a reset. You have to find it. Look on Apple's support site - they have an area for older imacs.

If you can't do these, because there's no signal from the USB ports, It would indicate a really big problem - motherboard.

One cheap solution, if your motherboard is fried, is to go to Ebay and look for one like yours - if you're in a metropolitan area localize your ebay results for your area so you can pick it up and test before paying. You might be able to get one of these things for 100 bucks or so. Pull both machines apart (a total PITA but I've done it many times) put your hard drive in the "new" imac and off you go.
 
Thanks for the advice. I think I'll test the battery first as it that will be the cheapest way to go.

I'm not getting ANY power to the keyboard or mouse there is no way I can zap the PRAM and I've waited 30 mins for the CD to show up with anything.

Unfortunately, I have this feeling that the board is gone...
 
Got it to work - kinda. While is was upside down I pressed the button on the motherboard and it did boot again. Only thing is that you have to use that button. Sounds like the motherboard is starting to go. Moving all needed files as I type this.

Thanks for all info guys.
Cheers.
 
Situser: If you have to keep hitting the CUDA button, that's an indication of a dead PRAM battery that won't jold a charge. You might try putting in anew battery, hitting the cuda and leave the machine plugged in but off.

Had the same problem a few years ago with some Motorola 3000s (Mac clones). We would turn off the power on each machines surge protector every night - due to frequent power outages at the time. Solved problem by replacing PRAM batteries, pressing the cuda and leaving the things plugged in to live sockets. No more problems.
 
Here's the update - replaced the battery. If I shut down, the computer will still no boot. Have to press the button. Next step - find a motherboard.

Thanks for everyone's input.

 
Most of the time it is fine and wakes up. Only occassionally does it freeze and I ahve to do a hard reboot.
 
Let it on - sleep - for a while. Then try a reboot with resetting PRAM - Hold down Command, option, P & R keys till you hear second tone.

Another trick is to try repeated cold starups holding down the shift key - starting in Safe mode. If this works consistently, it's unlikely to be the board.

You might also disable Classic at startup - System prefs/Classic - uncheck "start classic at login".

 
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