23" Cinema HD Display Won't Illuminate, LED Flashing Short-Short-Long

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Level 1

26 points

23" Cinema HD Display Won't Illuminate, LED Flashing Short-Short-Long

According to Knowledge Base Article HT2811, the LED Flashing Short-Short-Long means "the display is detecting a backlight error." Does "error" mean "failure" of a component? Is it not the case that failure of the backlight means the LCD is bad? If it were the inverter that failed, you would be able to see the image but it would be dim. Will replacing the LCD take care of the "backlight error"? How do you take this thing apart?? Context:the display is 18 months old; it is not covered by AppleCare; I bought it one week ago in this condition for $50.

Power Macintosh G3 Rev1,400MHz/1GB/73GB 15K SCSI/Combo/Radeon 9200 128MB, Mac OS X (10.4.11), MacBook Pro Core 2 Duo 2.33GHz/3GB/250GB; Power Mac G5 DP2.5GHz/4GB/700GB

Posted on Sep 20, 2008 3:07 AM

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Answer 1

japamac

Level 7

24,400 points

Sep 20, 2008 9:32 PM in response to Toolshed4

Does "error" mean "failure" of a component?

If the graphics card is capable of supporting the displays optimal resolution, typically, yes, this means component failure.

Is it not the case that failure of the backlight means the LCD is bad?

No, it is not the case.The backlighting system and the LC panel are different in respect to the error.

If it were the inverter that failed, you would be able to see the image but it would be dim.

No. If the inverter has failed, there will be no image. The image would be dim if CCFL lamps were failing, but the inverter was still working.

Will replacing the LCD take care of the "backlight error"?

No, as the backlight system is different than the LC panel. I'd consider the inverter board to be culprit. Could also be CCFL backlight failure at a connection, etc.

How do you take this thing apart??

Apple Cinema Display Take Apart

Good Luck!

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Answer 2

Toolshed4 Author

Level 1

26 points

Sep 28, 2008 12:18 PM in response to Toolshed4

Thanks for an informative answer. However, it turns out the error message is shot-long-short, meaning the power supply, and not the backlight. Switching out the brick with the one from my other 23" makes no difference.

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Answer 3

Toolshed4 Author

Level 1

26 points

Oct 8, 2008 6:57 PM in response to Toolshed4

I sold the Cinema Display without resolving its issue for more than I paid for it, but well below its retail value. The new owner took it to generic computer shop and they connected the power brick from a 30" Cinema Display to it and it came on immediately and has been working ever since.

Why didn't I think of that??

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Answer 4

ClarkDV

Level 2

185 points

Oct 9, 2008 2:40 PM in response to Toolshed4

In your previous post you stated that you switched the PSU with one from another 23" Cinema display that you had and nothing changed.

Why, then, when the fix-it shop switched in a PSU from a 30" would it start working?

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