Apple Hardware Test won't finish - possible disk problem?

[InfoTime]

Apple Hardware Test won't complete. It seems to stop after about 20 minutes. I can still move the mouse, but it's very jerky. The time shown next to "Total Time Testing" has not updated in several hours.

I suspect there's an issue with the hard drive. User tried to install upgrade to Yosemite and it failed with an error about some type of disk issue (sorry, don't have the exact error, but searching on that error indicates a disk problem). Disk Utility from the installation utility and with the Mac attached to another via Target Disk Mode reports no issues.

Can't boot my copy of Disk Warrior. Screen stays white with Apple logo. Might be that my copy is too old for this i5 iMac. Super Duper almost makes a complete copy of the disk to another device, can't find exact error right now.

I was hoping that the Apple Hardware Test would tell me the answer, but it won't finish. I've run the native test and used the Option - D to get it to download the test.

I hate to open it up and replace the drive just to see if it makes a difference. I'd like a better diagnosis. Any thoughts?

 

[InfoTime]

A follow up to my prior post about the AHT not completing. This post on Apple's discussion forum describes the symptoms I'm seeing to a T. For that poster it turned out to be a logic board. But at one point wasn't sure whether it was a logic board or hard drive. I'm doing a clean format and install and see if it holds up.

 

[InfoTime]

I booted from a USB drive with Yosemite installer. Ran Disk Utility. It found errors it couldn't fix. I erased the drive, installed Yosemite and restored from Time Machine backup. Computer seems to run fine. Only question the hardware test.

If I run AHT now I get the same results as in my OP. Hmmm.

 

[InfoTime]

Took the machine to the Apple Store today. Turns out the hard drive is bad as they found after their preliminary scan:

What's frustrating is that I couldn't isolate this myself. I have Disk Warrior, but the machine wouldn't boot with the Disk Warrior CD. I could have possibly ran Disk Warrior against the iMac by putting it in Target Disk Mode and connecting it to my Mac. I didn't try that since I figured my copy of Disk Warrior probably didn't work in Yosemite anyway. I could have pulled the drive and connected it to a Windows machine where I've got tools to test the drives, but didn't want to do iMac surgery unnecessarily.

So, the question: how could I have tested the drive myself without having to drag the whole machine into an Apple Store?

 

[giuarb]

It really sounded like a logic board error. Did u end up paying for the hard drive replacement? Was the logic board ok?

Took the machine to the Apple Store today. Turns out the hard drive is bad as they found after their preliminary scan:

What's frustrating is that I couldn't isolate this myself. I have Disk Warrior, but the machine wouldn't boot with the Disk Warrior CD. I could have possibly ran Disk Warrior against the iMac by putting it in Target Disk Mode and connecting it to my Mac. I didn't try that since I figured my copy of Disk Warrior probably didn't work in Yosemite anyway. I could have pulled the drive and connected it to a Windows machine where I've got tools to test the drives, but didn't want to do iMac surgery unnecessarily.

So, the question: how could I have tested the drive myself without having to drag the whole machine into an Apple Store?

 

[InfoTime]

This was a machine I was working on for someone else and I don't recall exactly who it was or what the end result was. But, I'm pretty sure I installed a new hard drive and it was OK.

 

[giuarb]

It was hard drive related for me too!

This was a machine I was working on for someone else and I don't recall exactly who it was or what the end result was. But, I'm pretty sure I installed a new hard drive and it was OK.