Saturday, September 11, 2010

Apple 24" LED Cinema Display Teardown

Hi Blogosphere!

This post is a byproduct of a small problem I was having with my Apple 24" LED Cinema Display. I originally purchased the display with a 2009 Mac Pro in March of 2009. I'm being totally honest when I say it was really "love at first sight" with this unit. The clarity! The brilliance! The glossy screen not being a problem in real life use!

Knowing that I had just spent a boatload on a new rig (and also being an Apple fanboy since 1996) I knew I should get AppleCare protection for this setup, but decided to be frugal. "I'll get it before the first year is up..." I kept telling my self. Well, 365 days came and went and there still was no AppleCare purchase. Oops. "Well, I made it the first year, so I'm probably in the clear from any random hardware failures..." was the thought in my head when I realized I had missed the boat.

Apparently Murhpy himself heard me utter that phrase when his Law struck me straight across my jaw. On the morning of April 25, 2010 (exactly 45 days out of my 1 year warranty period) I went to go use my machine as I had every day since I owned it. I hit the space bar to wake the display from sleep and nothing happened. I proceeded to reboot the machine, check all the cable connections (I was using a mini displayport extension), reboot again, and still nothing.

Then I started the next round of diagnosis - lots of adult flavored words usually reserved for rated "R" movies, panic, shortness of breath and finally remorse. My $899 monitor is now a 22 pound paperweight. At that point I decided to take my chances, tuck my tail between my legs and haul it down to my local Apple Store and beg the Genius Bar for a one time exemption. Much to my surprise they were sympathetic to my plea. This was only the second display of this model they had ever seen brought in for any repair - warranty period or no. I can only assume they only saw my black screen as a challenge.

Five days later I get a call from the store. "We've fixed your monitor, come pick it up at any time!". Oh my goodness - they fixed it and they did so under "warranty", or more appropriately a no charge favor. Woohoo!

Here's a list of parts they replaced, just in case anyone wants to know:

661-4823 Logic Board
922-8669 Display Function Cable
922-8679 All-In-One Cable

Why is all this important to a teardown? Well, apparently Murphy takes great joy in striking me twice. About two weeks ago I started to see what looked like "warped paper" in the lower left corner of the display. It was as if something had bent the LCD back into the monitor and caused a crazy "bulge" in the image protruding into the back of the monitor.

Well, let's see now. It has been about 120 days since I last brought in the monitor to the Apple Store. Did I really think I could convince the Genius Bar to do a gratis repair a second time? I really didn't want to push my luck as their work was only warrantied for 90 days from the date of service. Also, looking at the problem I really didn't see how what they did could have possibly affected the LCD panel itself - they just swapped a bunch of cables.

Hmm...how does this thing come apart? Checking iFixIt.com didn't reveal a magical teardown guide, but a couple of forum posts later I finally realized that these are just like the current iMac model design, just short a computer inside. So, I read up on iMac teardown, watched a couple of youtube.com videos and found the secret - suction cups! The outer glass is simply held into the outer frame by a series of magnets.

I was in business now - except for the part about what do I do after I get the outer glass off? I haven't been inside an Apple monitor since the days of the 15" RGB CRT days in the 90s and I certainly hadn't taken apart an actual LCD panel beyond removing a display or two from various Apple portables. This "bowed LCD" problem was deeper than that - it required actually tearing the LCD unit apart even further. My pictures below will describe better than I can in words, so here we go!

Teardown Steps:

1. Using suction cups pull the outer glass assembly from the display bezel. This is well documented elsewhere on the web. I'll spare details here.

2. There are six torx (T10) screws holding the LCD panel to the frame - three on both the left and right sides.

3. Once the screws are out you can carefully pull the LCD panel up and away from the frame to expose the connected cables. There are four of them - I'm guessing they are: display (noted above), power, USB and possibly microphone. I'm totally not sure of the fourth one, but who knows...


OK, now I'm able to remove the LCD unit from the frame. Put the frame aside - we're done with that for now. I'm still no closer to a diagnosis on why my LCD panel is warped - from what I can see the LCD is intact as I would expect. Deeper into the assembly we go!




4. There's two pieces of tape protecting the lower left and right corners of the assembly - gotta remove those.

5. There is an EMI shield protecting the LCD digitizer board, but hooked into the outer metal frame. We need to remove that too. It's held in with three phillips head #1 screws.


6. Now to remove the left and right mounting brackets that held the LCD unit to the frame. These are what holds everything together in step 1. There's three torx (T10) screws on each side - remove them. The brackets have been graciously labeled "left" and "right" for re-assembly.

7. There's two black tabs on the bottom of the LCD unit used to aid in removing it from the frame. These act as tape holding together the LCD plastic housing and the metal frame. Peel them both off carefully.

8. Now with a plastic flat tool you can pry the metal frame from the plastic LCD housing. There's tabs to release all the way around. With some patience the metal frame will pop off.



9. OK, the metal frame is off. Now what? I still don't see any obvious defects. Time to remove the LCD panel from the plastic housing (and underlying LED backlighting assembly). There's a bit of metal mesh tape on one side holding the LCD to the plastic - peel it back.

10. Now the LCD panel can be lifted from the backlighting assembly.


Ah hah! I found the problem!! As the pictures below reveal the rubber stripping surrounding the backlighting assembly in the problem area had worked itself loose - protruding slightly into the viewable area.


I simply peeled it back and carefully re-applied it in the proper position. Viola - my $0 fix on my $899 out of warranty monitor!


After much relief, now I was very worried that I had goofed somewhere and/or I wouldn't be able to re-assemble the beast. I carefully followed my instructions above in reverse and much to my surprise and amusement I'm writing this on my now back to normal display!

I hope this helps someone out there who is looking to do an out of warranty fix at some point in the future.

Enjoy!

4 Comments:

At 3:41 PM, Blogger mbrick said...

Nice fix! I sure didn't expect that to be the problem from what you described. These were also the first teardown photos I have come across.

 
At 10:30 AM, Blogger Maarten E said...

Thanks for your tutorial!
Just fixed my own screen with the same issue! :D

 
At 9:20 AM, Blogger Justin Brent Watkins said...

Thanks for posting this--I have the exact same problem with my display.

 
At 9:20 AM, Blogger Justin Brent Watkins said...

This comment has been removed by the author.

 

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