View Full Version : Clamshell Bug in Mountain Lion

Fresh Pie
Jul 27, 2012, 10:56 PM

I know there is another thread with a similar title, but the user who started it was referring to a "bug" that has been around since Lion.

Anyway, my problem is that whenever I turn my Mac on while clamshelled, the integrated display and glowing Apple logo stay on despite the lid being closed. To turn them off, I have to open and close the lid and wait for the blue fade to take effect; no big deal but still a slight annoyance.

I'm wondering if anybody has the same issue, and more importantly, if anybody has a solution, like a terminal command line.

Fresh Pie
Jul 30, 2012, 02:16 PM
It seems the issue is caused by Mountain Lion not detecting displays on startup, so it doesn't acknowledge the closed lid. By pressing command + F2 or option + clicking the Gather Windows button in Displays prefs, I can detect displays manually.

I've spent a while trying to write a script that would do either of those things and put it in my login items, but using F2 as a keystroke (rather than actually clicking it) plays an error sound. Also, System Prefs doesn't acknowledge "option down" for some extremely bizarre reason.

Fresh Pie
Jul 31, 2012, 10:27 PM
Alright, for any future people who find themselves with this problem (the laptop screen stays on even when the lid is closed as the computer turns on), I've developed a workaround.

I found the binary online that performs the display detection, and threw it into an app that I attached. If you put this app into your login items, the closed display will shut off on startup.

BTW, if you aren't experiencing the same problem as me, the app will apear to launch and almost instantly close; it isn't some weird malware process.

Aug 1, 2012, 02:17 AM
Thanks Fresh Pie,

I had this bug in Lion,but not yet in ML. Thanks for writing the script.

Fresh Pie
Aug 1, 2012, 06:47 PM
No problem. I'm fairly annoyed to learn that it was an issue with Lion too rather than just being a glitch that Apple forgot to resolve before pushing Mountain Lion to their servers.