MISSING BRIGHTNESS CONTROL SLIDER on 27" Cinema Led Display

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ILoveSax Author

Level 1

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MISSING BRIGHTNESS CONTROL SLIDER on 27" Cinema Led Display

There is a bug in the Apple Cinema Display or the iMac that controls it.

THE CINEMA LED DISPLAY BRIGHTNESS CONTROL SLIDER IS MISSING.

1. The apple support did not know anything about the problem.

2. It happens over and over on both of my iMac/Cinema systems.

3. I fix it, and then it happens again.

This time, after numerous unsuccessful trys to get the brightness slider to work on the Cinema Led display, I tried holding both keys down at the same time:

"Command" +"F1", and low and behold, up popped my Display Preferences WITH THE BRIGHTNESS CONTROL/SLIDER ENABLED!

*************APPLE SUPPORT, PLEASE TAKE NOTE AND GET THIS PROBLEM FIXED PRONTO. IT IS VERY FRUSTRATING TO HAVE TO FIX THE SAME PROBLEM OVER AND OVER!*******************

Apple Cinema Led Display 27"-OTHER, Mac OS X (10.6.8)

Posted on Sep 29, 2011 9:16 AM

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Answer 1

ILoveSax Author

Level 1

0 points

Sep 29, 2011 9:20 AM in response to ILoveSax

P.S.

I reset the iMac numerous times and that did not help at all.

1. I unplugged both Cinema display, and iMac

2. I held the powder button for 1 minute.

3. Replugged everything

4. Pressed and held the power button until it "made the startup sound", then

5. Pressed and held "Option"+ "Command" +"R"+ "P" until it made the "startup sound" again.

Still, the brightness control would not come up until I pressed "command + F1"

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Answer 2

gooober

Level 1

41 points

Oct 3, 2011 4:19 PM in response to ILoveSax

Mine just started missing yesterday after bringing my Macbook Pro in from the living room and hooking it back up to the 27" Cinema display.

No longer do I see a brightness control for the Cinema. Command + F1 just turns on mirroring and doesn't reveal the slider for me. Very frustrating as I used to adjust the brightness of the Cinema often.

:|

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Answer 3

rudy_

Level 1

0 points

Apr 30, 2012 11:32 PM in response to ILoveSax

The exact same thing has happened to me.

I am running a 27" Thunderbolt display off of a Mid-2011 MacBook Air.

Suddenly, last week, my brightness control keys on my external keyboard stopped affecting the brightness of the Thunderbolt display. The brightness keys on the MacBook Air, though, still affect the brightness of the laptop's screen.

I went into the Displays preference pane, and sure enough, the brightness slider has disappeared.

Have you been able to resolve this? (zapping PRAM, etc doesn't work.)

I'm wondering if this is a glitch that came with 10.7.3...

Anyone have any ideas? I have no way, now, to control the brightness of my Thunderbolt display. It is EXTREMELY frustrating.

rudy

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