iMac G5 won't boot to either HD or CD

Question

iMac G5 won't boot to either HD or CD

I am working on an iMac G5 (no iSight) that gets power, but boots to the little folder with the ?. I have tried booting to the hardware test CD that came with the computer, and the OS reinstallation CD that also came with the computer, both with the same result. If I hold down the Option key while booting, it sees both options (hard drive and cd) but when either one is chosen to boot to, it appears to be in a loop and comes back to the same screen to choose something to boot to.

I have removed the HD and run Disk Utility to repair the disk. It repaired an invalid leaf record count, but that didn't fix the problem either. I have tested RAM to no avail, I have reset the SMU. I am afraid it might be the SATA channel(s) on the logic board. Any other ideas would be greatly appreciated!

Patty

iBook G3, Mac OS X (10.3.x), I also have an iMac Flat Panel

Posted on Dec 17, 2008 10:09 AM

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Answer 1

a brody

Level 10

82,941 points

Dec 17, 2008 12:14 PM in response to Patricia Van Cleave

Try replacing your clock battery.

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Answer 2

Dec 17, 2008 1:11 PM in response to a brody

Thanks for responding. I tried a new battery, but it didn't fix the problem.

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Answer 3

Dec 17, 2008 3:02 PM in response to Patricia Van Cleave

By the way, I don't get a chime at startup, either.

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Answer 4

MGW

Level 7

27,041 points

Dec 17, 2008 3:15 PM in response to Patricia Van Cleave

I know you have tested the RAM, but try switching it around and starting with/without different sticks. No chime can be an indication of faulty RAM.

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Answer 5

Rod Hagen

Level 7

32,000 points

Dec 18, 2008 3:29 AM in response to Patricia Van Cleave

Which model is it, Patricia?

The "ALS" model or the earlier one from late 2004 to April 2005?

If it is the earlier one what do the capacitors on the motherboard/ midplane look like? Any sign of bulging or leakage? See http://www.flickr.com/photos/23270082@N03/2644122775/ for an example of a leaking one, but a very slightly bulging top on one can be just as bad. http://jimwarholic.com/2008/07/how-to-repair-apple-imac-g5.php provides some more images etc.

THose "invalid leaf" issues can be devilish to get rid of , by the way, so even if DU said the drive was repaired you should run it again to make sure it comes up "clean" on a second reading.

Cheers

Rod

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Answer 6

Dec 18, 2008 9:25 AM in response to MGW

I tried each RAM stick individually in each slot, then tried both together and switched slots. I think I have tried every combination of RAM now. Nothing made any changes.

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Answer 7

Dec 18, 2008 9:46 AM in response to Rod Hagen

This is the earlier model, from August 2004.

Would the leaf record count keep it from booting, but still allow the hard drive to be seen as a boot option? I will run Disk Repair again and make sure it's clean. I will let you know if it helps.

Thanks,

Patty

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Answer 8

Dec 22, 2008 9:46 AM in response to Patricia Van Cleave

Sorry for the delay in working on this.

I have run the Disk Repair a second and third time. Now the message is "invalid map code". 1 HFS volume repaired. 1 volume could not be repaired.

I suspect at this point the only option is to format and reload. Since the iMac G5 won't boot to a CD either, I will do the format in target mode. Then I hope the computer will boot to a CD once the hard drive is clean.

Patty

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Answer 9

Dec 22, 2008 10:50 AM in response to Patricia Van Cleave

"I have run the Disk Repair a second and third time. Now the message is "invalid map code". 1 HFS volume repaired. 1 volume could not be repaired."

You will need a stronger utility to repair. The following will do the job:

DiskWarrior
Highly recommended for *directory damage* repairs.

TechTool Pro
Multi-functional utility.

Drive Genius Multi-functional utility.

You will need to make your own decision on which to purchase. Read up on them on their websites because each does something a little different.

You must use the versions that are compatible w/your OS system & keep the utilities updated to avoid damaging/harming/trashing your system.

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Answer 10

Dec 29, 2008 12:47 PM in response to Baby-Boomer-USofA

OK. The holidays have slowed me down working on this. I have TechTool Pro 4.0, which I ran on it with no changes.

I have now formatted the hard drive thinking that if it was blank, maybe I could boot to an installation CD, but that hasn't changed, either. I'm about to give up on this one. The hard drive has passed tests. Unfortunately I don't have another SATA drive with a Mac OS on it to try booting to. I did try using our SATA drive with XP, just to see if it would recognize anything more than it was, but it didn't. Now I'm wondering if it's possible that the optical drive is bad.

I also wanted to install a generic version of OS X 10.3 on the troublesome hard drive via USB, but wasn't allowed to do that. I was told I couldn't boot to that hard drive (I don't want to boot to it via USB, I only want to install the OS!)

Any other suggestions would be very much appreciated.

Patty

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