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Ericompton

macrumors newbie
Original poster
Dec 21, 2018
7
0
I'm not quite sure on the year as this computer is a family members. They gave it to me and I'm wondering if there's anyway I can fix it without spending more money than it's worth. As the title states it's an iMac with an i5 processor I would suspect it is about a 2014. When powered on it chimes and that's it. They paid a repair person to replace the screen but that didn't fix it. I suspect the video card is the problem. I plugged a mini DV to HDMI cable from the iMac to my TV and got no picture, but when I did the same thing with my macbook pro I got a picture. The computer was in good shape prior to this issue and I hate to just scrap it. Just looking for some suggestions from more experienced techs. Thanks for looking and Merry Christmas.
 
Got an external USB3 drive with a bootable operating system on it?

Try that as it may be the hard drive that has failed. That paying a 'repair person' to fix the screen sounds bad. 2012 iMacs and later have a fused glass screen that must be replaced at a cost of around $500 so who knows what has been done to it. Trust this was a Mac service repair guy as slicing them open and reconnecting cable and particularly screen cables can be a little tricky.
 
The repair man replaced the screen is what I was told. In the event of HD failure will the monitor just remain black? I have an external HD with time machine backing up my macbook. Is it possible to boot from that just to test the issue? Thanks!
 
Additional information. I'm trying to create a bootable USB (tips on that would be great. Not sure where to download a .dmg for El Cap or something close). I turned on and tried to press and hold and R, no results...then I tried a pram reset and got 2 chimes. I left it running and the fan started spinning. So for what it's worth that's what is and isn't working. Still just an unresponsive screen.
 
I think you need to have downloaded El Capitan via the App Store previously or you may be between a rockm and a hard place. Use the appropriate Diskmaker X to make a bootable 8GB thumb drive, pop that in, reboot and hold down Option and proceed with the install.

Mojave has not made it easier with purchases having previously included all downloaded operating systems, but that does not seem available any longer.

Perhaps another contributor will help with where El Cap is available but Apple certainly do not havebit available down nunder.
 
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Are you certain that the screen stays black? (no image at all)
Make sure by trying to boot. Let it sit for a couple of minutes, so it does try to boot, and --- if the video was working properly, you would expect to see (something/anything) on the screen. After that wait, shine a bright light into the screen from several angles. If it needs to log in, you may see something that looks like a login screen in the center, even if the image is very dim (because the screen backlight is not powered on to provide normal brightness to the screen) If the Mac is set to login automatically, you should be able to see (something) at the top of the screen/menubar. You have to shine your light into the corners, looking for the Apple icon in the top left corner, or the clock near the top right corner, or the dock/icons along the bottom edge of the screen, or ANY other icons/files, or any other screen elements. Those may be difficult to see, but you need to rule that out.
(If you can see dim items, then there's other parts that might be replaceable, not the LCD screen itself. That will then depend on which iMac model you have)

just my 2 cents: Sounds like your relative was taken for a ride by that repair shop. I hope they didn't have to pay much for the display replacement.

It can help if you can determine which iMac this is... You can find the serial number for this iMac on a label on the bottom of the stand. You can then search for "Apple serial numbers", where you will see several sites that will decipher the serial number, telling you the exact model, and other tech specs for that iMac.
 
Turns out they were mistaken. It's an i3. Mid 2010 3.06 Ghz. Model A1311. I have previously shined a light to make sure it wasn't a backlight issue and thought that trying to plug it up to my TV would eliminate that possibility. At one point I had a .dmg of el capitan on my macbook and put it on a thumb drive but I have misplaced it at the moment. Newton's law
 
You can find the service manual for this. Search for the file: imac_21_mid10.pdf
The service manual has steps to troubleshoot the diagnostic LEDs on the logic board.
But, I suspect that you have a bad video ribbon cable (displayport cable) -- easiest to replace
or, the video card -- more involved to replace (and you have to find one that works, I suppose)
And, last, but not least, the logic board may have failed.
I will guess the video card is the culprit. I think you mentioned that already in your first post.

Not sure which of Newton's laws you have mentioned. Maybe you became ensnared by "Murphy's Law" :D
 
Gravity... everything falling down around me. Lol.
One other bit to add. I stuck a DVD in the drive to see if I could eject it. No luck. I also have pressed the volume up and down keys to see if I could hear the pops sounds it usual makes. That didn't work either. I know the keyboard is connected because I'm able to reset the pram. Would the volume and eject work if it was a graphical problem? Thanks
 
Are both the mouse and keyboard wireless (bluetooth), or wired USB?

You should able to eject the DVD: restart, holding your left mouse button down. The DVD should eject (or make the eject sounds, even if the drive is not able to fully eject the DVD), just continue to hold the left button down. This will work best with a wired USB mouse, but SHOULD also work with bluetooth mouse, if that is what you have available. I would expect that DVD to eject shortly after the screen lights up --- however, with no screen, just hold the left button. 30 to 45 seconds should be long enough to wait.
I think it is possible that the iMac does not get far enough in the boot process to support the volume keys (the operating system has to finish loading) - but, the DVD should eject, particularly by holding the left mouse button. The eject at that point doesn't need an operating system, it is a firmware command.
 
Both the keyboard and mouse are blue tooth. The drive makes a sound when it turns on (since there's a DVD in it) but no change if holding the left mouse button down or not.
 
Try a USB mouse, at the minimum. That doesn't have to be an Apple-brand mouse. Any USB mouse would do this.
Should be easy to borrow, if you don't have one.

If THAT doesn't eject the disk, then something has failed on the logic board.
The only way to get the DVD disk out of the drive will be to open up the iMac, remove the optical drive, and remove the cover on that drive. The DVD will be loose inside the drive.
 
It's 8 years old, going on 9.
Whatever you do, don't spend too much money on it.
 
Bad news for me. I created a bootable thumb drive and tested it on my laptop, worked fine. Stuck it in the iMac and same results, fan runs, chimes, black screen. Bummer I was really hoping it was just the HD. Any other suggestions, I'm not against opening it up. I replaced the keyboard on my macbook, now I can do anything lol. Thanks
 
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