I have an Apple Cinema Display (20-inch DVI 2005) that isn't working after installing the 10.10.3 update. The screen is just blank, and the power light just blinks a few times every 30 seconds or so. I use this as a second monitor with my iMac (27-inch, Late 2012). Any way to fix this? Thanks!
iMac, OS X Yosemite (10.10.3)
Howdy Josh,
It sounds like your LCD Cinema Display's power light is flashing 3 times quickly a couple times a minute. According to the following article it sounds like you should reset your PRAM:
Apple LCD displays: Power light flashes
Pattern Meaning short, short, short The display is detecting wrong video format or an unsupported resolution.
Verify that your equipment is compatible and restart the computer. If the issue continues, reset the PRAM
If it is not three short blinks, refer to the article for other troubleshooting for that. Here is also the updated PRAM reset article for Yosemite:
OS X Yosemite: Reset your computer’s PRAM
Thank you for using Apple Support Communities.
Cheers,
Sterling
Thanks for the suggestion, but sadly it didn't take care of the problem. I tried it 3 times. After watching the blinking light closer, the pattern is short, long, short. And according to your link that just means I should make sure I'm using the correct power adaptor, which I am. It's still the same factory power adaptor I've been using with it for 7 years or so. This started right after I did that OS update, so I feel like it has to have something to do with that. Any other thoughts?
Thanks!
Not sure this is for everyone, but this might be a workaround. I had the same problem, but this worked:
after a restart, I waited until it would have been the password screen
entered my password as usual (blind with no monitor)
used the command+option+power button hotkey to put the system to sleep
counted to 20
clicked the space bar, and the monitor started working again.
Could fail on a restart, but it's working now
Thank you for the update!
Next I would recommend the Reset the System section of the following article for additional troubleshooting:
Apple computers: Troubleshooting issues with video on internal or external displays
Reset the system
You can reset the Mac's parameter RAM and SMC.
Reset the resolution
Start by resetting the Mac's parameter RAM. If the display does not come up, was previously set to an unsupported resolution, and still results in no video:
- Start up in Safe Mode.
- From the Apple () menu, choose System Preferences.
- Choose Displays from the View menu to open the preferences pane.
- Select any resolution and refresh rate that your display supports.
- Restart your computer.
I would reset the SMC and the PRAM together, in that order one more time, then do the Safe Boot if needed.
Apple Cinema Display (20-inch DVI 2005) not working after 10.10.3 update
