2011 iMac screen goes and stays black
Ready to throw it out the window! I can hear it start up but the screen is black. Took it to get fixed and they reset the LCD cable and it worked at the store got it home and back to black. Now what?
I bought an iMac with this problem for a good price to solve the problem. I got it temporary worked around, maybe you can try it.
Unplugging the power for a while and putting display brightness to lowest seem to have worked around the problem for a while.
I think the built in power adapter or backlight board is the issue. These are both always powered when plugged in.
This week this workaround didn't work anymore and I'll replace both. I'll let you know what the culprit was.
Dennis van der Pool
Any ideas what’s going on here.
Same issue. Tested with 3 different invertor boards as wells as 3 different power supplies and 3 different screens. Still get random black screens but working fine on external monitor.
Anonymous UUID: E2C6C9FC-2B6D-4C49-920E-42CB10BC9EEF
I have the 2011 iMac 27 inch and in the past few months the black screen problem has started.
I have a second monitor attached and can see that the system is still operating normally, except for the black screen of course.
Hitting the “control shift eject” sequence works as does hitting the sleep tab on the drop down menu on the Apple symbol. To simply bring the main screen back on hitting any key on the keyboard seems to work, especially hitting the “eject” button.
So to me, clearly this is not a graphics hardware related issue, or an over heating one either.
I believe this is an operating system issue, one which I believe Apple could easily identify and fix if they had the best intentions of their loyal customers at heart. Maybe the want people to get so frustrated with the problem that they will go out and buy a new systems, or am I being cynical!!!
It would be interesting to go back to previous versions of the operating systems to see if at any point an update caused the problem to start but I don’t have the time or inclination to try this out.
I fixed it by replacing the faulty GPU. Same issue; only video at the external video output.
I tried another LCD, inverter and powersupply. No succes, so I replaced it with a K1200M with custom firmware.
for this issue it’s crucial to know if the external screen is attached as secondary or primary.
logon screen at secondary screen: LCD is not being. Initialized due to loose connection.
I found out troubleshooting that the external screen is mounted as primary when I disconnect the internal lcd partially.
The external screen get primary if the internal lcd is not connected right. if you get a loginscreen at the external screen, this might indicated a loose connection.
with the logon screen on the faulty internal LCD you will get a blurred background visible on the external. In my situation this was a result of a faulty GPU that didn’t feed the internal LCD properly.
I agree with Tony Wood , its only bad apple software , ( and a locked donw sytem so its hard to find settings )
even a 1 hour tel contact with a very helpfull Apple support agent did not point me in the right direction :(
can anyone help me my iMac won't turn on. I installed the gtx765m which I tried in the iMac on May 21, 2011 and it works perfectly. I tried the screen on another iMac and it works. could there be a problem on the main board?