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?