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1 iMac Will Not Boot With LCD Installed
Hi, I will preface by saying I fix Macs for a living and am pretty skilled at troubleshooting and diagnosing, but this one has got me a little stumped, so I’m looking for some second opinions.
I have a mid-2011 27in iMac that will not boot when the LCD is installed. It powers on starts loading the boot progress indicator, then goes to a white screen for a couple minutes and reboots. If I take the LCD off and use an external monitor it boots up and works normally every time. The condition is 100% reproducible. Weird, right?
Here’s troubleshooting I’ve done so far:
- Passes all hardware tests on ASD 3S145A EFI boot disk
- Replaced video card
- Installed known good hard drive and installed macOS High Sierra
- Installed known good power supply
- Installed known good screen inverter board
- Alternated pairs of memory to ensure no bad RAM or memory slots
At this point, I feel like it has to be the logic board, but looking for some additional input before I throw more parts at it since I don’t have a logic board laying around for this model.
Is this a good question?
Try this, either get the Apple service cable extensions so you can have the display connected but on the side or careful connect the cables but make sure you don't let the metal surfaces touch between the display and the case.
Did that solve it?
by Dan
@danj Thanks for the suggestion. I gave that a try, but unfortunately it did not change the behavior.
by Joe