iMac hard drive can't be read

[matthiastj]

So before this gets deleted since it looks like other threads, please read into the present issues because I have searched everywhere for the answer to this. It's an iMac A1224 and I get the flashing folder/question mark on startup. When I booted from an install drive and tried to find the hard drive with Disk Utility the only thing it show for an internal drive is "Media". It's a hard drive that cannot be partitioned or have it's partitions changed. It says that there is 0 space on the disk. I took the hard drive out of the iMac and used a USB to SATA cable and can read the hard drive perfectly when it's being used as an external drive. The user files are all there, but I cannot tell if any system files are corrupted. However, once I put it back in, I get nothing. Trying "Option" on boot up gives me nothing except any external drives I plug in to use as install disks. This isn't my computer, it belongs to a friend of my wife. I can get all the user data off I'm fairly certain, but would love to bypass wiping the drive and doing a fresh install. Not even sure that it would work. Could the cable to the Motherboard be shot? Could there be an issue with the motherboard itself? Thanks for any help anyone can give. I'm new here so I hope I posted this in the right spot.

 

[Samuelsan2001]

It is most likely the cable Apple have used some fairly flakey ones in the past especially in the 2009 - 2012 MBP. They are pretty cheap on Amazon or ifixit. Of course it could be the motherboard but for $20ish it's certainly worth a try.

 

[Fishrrman]

Before you do anything else, I suggest you get a second drive and do a clone of everything that's on the problem (iMac) drive to ANOTHER drive, just in case. If you can't save the computer, save the owner's data.

That's an old 2007 aluminum iMac, correct?

Once you get the iMac back together, you should connect an EXTERNAL BOOTABLE drive, and see if you can get it booted and running that way. Connect via either USB or firewire.

Even if you can't get it to boot from the internal drive, if you can put the existing hard drive into a USB3 enclosure (which is backward-compatible with USB2), you MIGHT be able to get it to boot from the same drive mounted externally.

This will give the owner a usable machine for the time being. It may not boot as quickly, but at least it will run.

I think the best advice you could give the owner at this point is to "start looking for a replacement".
Nine years out of the old one is longer than most folks get!