My experience was that I had put up with it as an annoyance for a good while, but when it got really bad this summer, I contacted Apple and they agreed to replace the panel even though it was over a year out warranty.
If others have having similar experiences, then it sounds like its something on Apple's radar, even if they are not being particularly forthcoming about it, but rather waiting until people complain. In the UK at least - the flipside is that others (in the US) are reporting that they haven't been able to get panels replaced, even under warranty. I don't know if this difference in result is down to time (ie they weren't willing to replace panels initially, but once it became evident to them that there was an issue, they became more willing), or if its a gepgraphic lottery.
In the end, I had no complaints at all - stuff goes wrong, but its how companies deal with the things that go wrong that really counts, and replacing a 27" LCD panel over a year out of warranty was pretty good really.
They just made me take it into an Authorised repair place to get them to look at it and confirm that there was an issue that wasn't fixable simply by taking it apart and cleaning it. After that they were happy to authorise the repair.
Yeahhhh, maybe the EU is a big emerging market for Apple-stuff and rumours about bad quality for lots of money for a so called cool-perfect iMac device (Germans love cool perfect devices...) is an issue. I don't really know where they make their volume of sales or big money. But I know that lots of people and friends in my perimeter are buying cool Apple-devices - but not really Mac-PC's.......If already you have a iPod/Pad/Phone, you want the MAC, and if this BS, you/they don't want it... If somebody ask's me, then I always give an approbiate answer - everything is cool, fast, straight-foward, but this annoying display......
Okayy,, now I'll launch a request for my 2nd display replacement (beyond warranty) towards Apple-support -I'll report ........
I would really like to know, if newly replaced displays (after 3 - 6 months) are flawless, can anybody report??????
I only had mine replaced at the end of June, and its still fine - but then it took over a year to manifest itself in the first place.
If it does happen again, I like to think I'd have a good case to have it replaced again. The fact that they have been prepared to replace it so far out of warranty already suggests they are taking responsibility (albeit only after receiving the complaint). So if it happens again, there would surely be a strong case pointing at an underlying design issue of the iMac, rather than a faulty LCD panel per se.
Although saying all that, to have it replaced again in a year, by which time it would be over three years old, with a brand new iMac would be an incredible result.
PLEASE MAKE THIS THE LAST POST about this!
This way other people can know that IT IS POSSIBLE TO FIX (DIY) THIS PROBLEM!
This is for all iMac users that are out of warranty & can't afford buying a new LCD module.
I hope this message will not "mysteriously" disappear.
If it does we'll know that all these discussions are being watched & censored.
By 04:30 of the only video-repair of a (late 2009) 21.5inch iMac (http://www.youtube.com/watch?v=GONDMj0Glt4) I felt really desperate because I had the LCD split apart from the iMac's body with all its adhesive tape strips opened but it didn't seem to make a difference: the **** panel seemed solidly attached to its frame & there didn't seem to be anything else I could do! I didn't want to force anything, risk breaking some component & ruining my just-bought (2nd hand) iMac 21.5''!
So, as I had to guess it the hard way due to the lack of that part on that video, I will now explain my 10 steps so that no one else has the difficulty I had to accomplish this fix:
01 Slip a clean folded sheet under the iMac.
02 Get yourself a strong suction cup, apply it to the upper left or right corner of the iMac's & pull out the polycarbonate front.
03 Remove the 4 left + 4 right torx T10 screws around the LCD & copy their positions on the iMac onto the surface you'll lay them so that you later know which screw belongs to which hole. Sometimes screws want to be returned to their usual house. I must say already that, on my way back, this was what didn't turn out perfect: the holes on the right side (& just on that side) didn't match; they were like 1 or 2mm offset & the screws had to be half-screwed & inclined.
04 Pull the LCD out & incline it about 20 degrees from the iMac's body, just enough for your hands to slip inside the gap for you will have to disconnect 4 cables. You might want to ask someone to help you by holding the LCD from behind the iMac.
05 Disconnecting the 4 cables (#1: vertical sync | #2: backlight power | #3: display temp sensor | #4: LVDS) that link the LCD to the iMac's body:
Pay attention to the points where the cables connect or photograph them so that you'll know how to restore it on your way back.
Be very careful & patient for these connections are delicate!
The upper left one (#1) is a thin blue-tip strip that you have to pull to your right, the bottom left black one (#2) you have to gently pinch & pull both tabs down and the other two you must squeeze the sides to release.
Take your time.
06 With the LCD separate from the iMac's body, place it over the sheet with the front down.
07 Remove the 2 left & 2 right screws, from the sides that are shorter. 1 screw in each side is hidden under a little adhesive cushion that you must partially lift up.
08 Start opening/lifting (not removing) ONLY the adhesive tape strips that are helping bonding the LCD Panel to the frame. There are several sorts:
- aluminum/tinfoil mylar
- black thin plastic
- black thick rubbery copper square
09 Detaching the LCD panel from the frame:
Use a plastic or latex glove on your left hand (if you're right-handed) so that you don't stain the LCD's front.
You might want to try pressing the other side of the LCD panel upwards & verify it doesn't even seem to move. Don't get frustrated & don't spend a lot of anguish time (like I did) searching for some hidden screw or anything else that you might have missed. Understand that the LCD panel will only move up through the frame after you force it to. It is still attached to the frame by 2 left + 2 right tiny white tabs and 5 black ones on the bottom side — if you don't see these 5 it's because you haven't lifted the longest mylar tape strip enough.
If you are sure that you have removed all the 4 screws & lifted all the tape strips that covered the narrow gap between the LCD & its frame then grab your screwdriver (or something with a larger tough tip) & fit it on that gap beside a white tab that is closer to the corner beside the longest mylar tape strip. Force the LCD panel out of the frame while pressing it upwards on the other side with your other hand's thumb. Right after this place your screwdriver on the nearest black tab, push it down while pressing up the LCD panel & pulling the frame edges down with your nails. If you do it vigorously you'll start to see it come off!
This is the toughest part, specially if you do it alone, so it's a good time to remember the money you'll have to spend if you don't take that **** LCD panel out of that frame! In my case the price I was given from APPLE's assistance for the replacement of the LCD module was nearly €500, which was 90% of what I paid for my (2nd hand) iMac!
So be careful but PUSH, PULL, PRESS!
10 Cleaning the inside of the LCD panel:
If you got to this point: congratulations!
I didn't completely open/separate the LCD panel but just enough to be able to slip inside an anti-static cloth & gently clean that problem away!
Have a peek inside yours with lighting coming low from a side & you might recognize the forms of the stains that have bothered you for so long! It's dust that somehow, despite all the tape strips, gets into the LCD panel but I was too anxious to investigate it deeper, and the odds are that APPLE has no clue either. I guess that a removable dust filter before the fans could help…
So to prevent this you might want to avoid using your iMac in a dusty polluted room.
APPLE really deserves this tutorial for not having listened to (i)Mac-users in this & so many other problems!
This repair is NOT in this iMac's APPLE Technician Guide but, & here's a final thought, it's "funny" to verify how, after this fix, the LCD panel looks just as new...
Thanks a lot for this ultimate description of the DIY solution to the smudge problem.
Liked the video, fixing the screen with a cig in hand... Also, as you mention, when the going gets tough the video reverts to pictures...
Now, on my 24" iMac on which I had the screen replaced 3 times under the 3 year apple care warranty, I have a similar, but not same issue. It seems that the clear glass in front of the LCD is accumulating dust on the inside surface this time. This is different from the issue with the smudge between the LCD and the white back light surface. So there seem to be more than one issue at hand;
1. the dreaded back light smudge (fixed as described above)
2. the dirty glass cover inside (fixed by simply cleaning the inside of the glass cover)
Nevertheless, I am looking forward to see the brand new ultra slim iMacs in real life... I guess I am an Apple sucker...
for your ultimate Description of "open heart surgery" on a iMac-display for smuck-residues removement..... This will be my last option... But (as mentioned), I'll try the the "apple support (in the EU) - maybe-option" of replaycing my display for free (a new flawless one?). I would really would like to get on hand of this smudge-residue (wipe cloth with this stuff is ok), as I'm an analytical expert (C.S.I. xxx) in chemistry for a really big company (in Germany/EU, not Apple...). In my (our laboratory:
It would simply be fun for me finding out what this bsmudge really consists of......
Another twist to this sorry tale.
I took my 27" imac which was purchased January 2012 and still under warranty in for repair to my local apple store after the left hand side of the screen suddenly became 50% darker which seems to be another known issue with this model. Whilst there I pointed out the problems I was having with the smudging that had developed over time on the extreme upper left and right sides of the screen and was steadily becoming worse.
The rep was unable to comment on either issue but sent the computer off for repair to an authorised repair center and the result is that yes they will replace the LCD screen under warranty because of the fault with the dark left hand side but insist that the smudging on the extreme top borders is an enviromental issue caused by smoking and that the stains are on the inside of the protective glass outer which seems to be contrary to what the majority have experienced on this thread which is that the smudging is within the LCD itself.
The upshot of all this is that I am being asked to pay £78.00 for replacing the glass front as they claim to be unable to clean it to their own satisfaction and "enviromental issues" are not included under the warranty.
The question is who do I believe and does it make a difference either way because what is clear in this forum is that this particular model of imac seems unable to cope with even the average home/workplace "enviroment" never mind that of a smoker. I have even seen photographs posted on the internet of display imacs within Apple stores with the very same smudging, perhaps Apple store enviroment isn't up to scratch either or are they planning to put the blame on all those dusty potential customers....
I have no wish to be sarcastic, I am a long time user of Apple computers and until now have never had to make a complaint about their products but its time for them to own up to what is clearly a design fault and to rectify the problem.
IF ANYONE WANTS TO FIX THIS: check my 2012_11_04SUN post.
I didn't want to add anything else but: some days after that DIY tutorial post an APPLE assistant told me that he had heard this problem is due to the existence of a glue paste which, when heated up, generates that dust. Now that's an info I hadn't found anywhere... I wish he was wrong but I must say that the dust I found inside the LCD panel did seem to me finer-grained/powderier than plain house dust...
I had this same problem, that took over two years to manifest (computer is out of warranty, and without apple-care). I took the imac in to get the hard-drive replaced (it had been recalled), and called attention to the dark shadows behind the screen (what everyone has been describing here). My case was quite bad, the entire upper half of the screen, and all the way down both sides had dark smudges.
After about 10 minutes, a couple of questions about smoking and whatnot (I always use a hepa filter in the house for allergies), and they said they'd replace it, no problem, no cost.
When in doubt, always ask first before you take the repair on yourself!