iMac 2011 27inch i7 screen flicker dark left side

Hi John, looks like we are getting near to an understanding of the fault. The only thing I thought I would mention is that is extreemly dangerous to run an iMac with a loose screen as you are exposed to the power supply and LED driver. The PSU has about 380 V DC exposed on the side right next to the display pannel and the LED driver also generates about 200 V DC.

I have a similar problem and will give an explanation once I get to the bottom of it.

As promised, here is the easy guide to resolve the darkened/low dimming/flickering on iMac screens. No tools or knowledge needed.

[GUIDE] Fix iMac flickering and dark screen problems out of warranty

Ok. I think i have found the real root of the problem that causes all this flickering and darneking on the screen and why applying pressure works sometimes but it's not a permanent solution

There is a LED connector on the rear side of the screen (You need to remove the display from your mac to access it) located at the lower right corner (left corner if you look at the screen from the front) that may be causing all this trouble. It is hidden beneath the sticky silver paper and adhesive strips. The pins of this connector (both board or cable ends) may be loose, broken or not well soldered due to the stress, heat or whatever. This causes that power is not reaching the LED lights on that part of the screen and therefore, the dark corner and flickering when they are making contact and suddenly they are not.

I removed the connector completely, connected the screen again and power up the iMac and guess what? It booted up correctly with no errors but with the dark corner being permanent.

The solution is to fix the connector by soldering it correctly (maybe just a small push would solve it for you) or soldering the cables directly to the 6 points needed (The bigger two of the sides appears to be just physical anchorage for the connector). I'm currently doing that now. I'll update this entry with my results.

Meanwhile you can you can watch this video/photos i have just uploaded for you to see:

[VIDEO] iMac 27" (Late 2009) Flickering And Dark Screen. Faulty connector in LCD-LED.

Confirmed, i fixed the screen problems permanently by removing the faulty connector and soldering 6 wires directly to the points that you can see in the photos.

My iMac's screen brightness is now better than ever.

And finally, i made a custom wallpaper with the photos i have taken when my computer was open 🙂.

OK that is hands-down the best imac desktop photo ever, and I NEED IT! Is there any way you can post a link to the image so that I can use it on my imac too? SO AWESOME, YOU ARE A GENIUS!

Oh, sure, no problem. You can grab it from my Dropbox account:

https://www.dropbox.com/s/co0lz4o6jq1c1aj/iMac_Late_2009_wallpaper.png (46MB)

Enjoy! 🙂

Hi Kaos2K,

Have you had any problems with flickering/dimming since you have added the wires and soldered them? i can 95% cure the darkness on the left side of the screen with pressure from placing a pad but am looking for a more permanent way and have been seaching around EVERYWHERE this is the first 'fix' i have found. My dads coming over later today so i can explain what to do from the pictures and such and hopefully it will get done in the next few days. Will let you know when its done and the outcome. Thanks again!

Steve

Hi Steeveen.

I have also been searching around and around to know why this was happening and found nothing (Except for the pressure temporary fix) so i decided to check out myself and discovered what i have posted here.

Since i soldered the cables my brightness is 100% again and no signs of flickering or dimming ever again. The only "issue" i noticed was a louder buzzing that comes from one of the fans but this is probably being caused by some dust or something i touched when i was cleaning the inside of my iMac, nothing related to this fix i think.

The process was a bit difficult due to the small gap i had to perform the soldering. I have to cut the white plastic a bit to make more space. You are going to need patience and plenty time. (At least 1 hour).

I suggest you to use some kind of magnifiying glass to make the task easier and a pencil soldering iron (I used the JBC 14ST). Furthermore, you should pre-stain the wires you want to use (I used wrapping wires) and apply some Flux before soldering to make the soldering points more consistent.

You can find the complete set of photos in my Photobucket's album.

Honestly, i'm very very happy with the results and they worth the time 🙂

Good luck!

BTW: Be extremely careful with the blue flat cable (The one in the upper right corner of the image below, not the one the arrow points) as the flat pins are very fragile and could break or be damaged when re-connecting it to the main board, specially if you do it a lot of times.

Hey, I've shown my dad the pictures and showed him what my screen is like without the pad in there and he's said he will attempt to do it for me on Tuesday. Even if the fan buzzing is affected by this fix i'd rather have a louder fan than a dimmed flickering side of the screen but as you said its more than likely not, i'm not bothered either way

i've made a note of that and printed out your last message xD my dad will more than likely know but what do you mean when you say pre-stain the wires? also can i thank you again for the album, nice to see some hi res pictures of what is needed to do before someone diving in and doing it xD

I have no doubt i will be also 😝 and imo well worth the time, and alot cheaper

Thanks alot, will post back and hopefully with a fully illuminated screen with no problems xD (noted: about the blue cable, hopefulle this will be the only and last time i remove it 🙂

Thanks again Kaos2k!

Steve

With the "pre-stain" i mean you should apply tin (the metal that is used for soldering) on the exposed wires (on the metallic part when you peel off the plastic cover they have). That way, it's a lot easier to solder them to the board. If your dad has experience soldering he know what i mean for sure 🙂

Hi Kaos2k

Sorry i haven't replied sooner my dad has been away and unable to do it but is planning on doing so this tuesday, as for the wire you used is there a certain resistance needed? if you could let me know what one you used, would be a great help!

Cheers

Steve

I used wrapping wire AWG30 (I think) but you can use one of the same diameter. No need for specific resistance 🙂

http://www.electricheap.net/wire-wrap/24-purple-wrapping-wire-wrap-300-meters-aw g-30-cable.html

Yes i have this problem. I have just recieved my iMac back from an Apple Authorised Dealer,and it took them about 10 days to fix it.

The actual failure was Dark Patches on the screen,and on the repair sheet solution replaced LCD Screen.

I am 63yrs old and bad with my nerves (I live in England) This has happened to me 4 Times with the last iMac they gave me.

They replaced this early this year with a brand new IMac,but with in 3 months the Black Patches came back.

I got an Advocate to act on my behalf. The Advocate comes to my house,and she came just last week (Back end of June) with the bad news.

Apples stance on this is that you have had it repaired,and that it is in good working order,but it is only tempory i am just waiting for the Black Patches to come back,and they will.

My Advocate has went off to make an official Complaint to Apple,and she is looking into how you go about it in the small claims court,because i am do not qualify for a Solicitor. The internet is rife with these problems.

1. Flickering Screens 2. Yellow tinges 3. Black Patches.

Apple will not admit that it is a hardware problem at manufacture. That means your Apple Care Plan is not worth the paper it`s wriiten on. They will keep repairing your computer while undercare of your Apple Care Plan,after that you are on your own. To replace a screen when out of warranty costs you £500.

In the warrenty there is a word "Bio Hazard" This means Dust,Air freshner,Smoking,Cleaning Fuid,and so on.

I am just waiting now for the Advocate to come back with more information from Apple. Ongoing?

Hello everybody!

Same problem here, iMac 27 mid 2010, one year after warranty expired, the screen went dark(er) on bottom left side as mentioned in some posts before. When I start the computer it is ok for about 5 minutes, but then … you know the rest.

After going over all forums on internet about that same problem I called my AASP (Apple Authorized Service Provider). Of course they knew about that problem, but they would not admitted that is a common issue. They said that repair will cost aprox. 500-900 Eur (610-1100 Usd). No way!!

So I called a friend of mine who is a truly wizard for electrical appliances and this is what he found.

As soon as he saw the machine he said it could be something with connections or some other stuff which can be surly replaced. The only think he was worried about, was taking the machine apart.

To make a long story short, here are some photos where you can see, what was the problem in my case (if this is factory mistake, I cannot say for sure).

On firts photo you can see right side connector which is ok. On second photo you can see left side connector which is one or two mm off so after a while connection and fuction get lost. I asume that's why in some cases gets better after aplaying some pressure on that spot.

After adjusting this connector on the right place, the screen is working ok.

If you are planning to take computer apart yourself, be careful, it is quite complicated if you are not familiar with technical stuff.

If you need any further information, just send me an e-mail.

Best regards,

Enejus

Enejus

You said to email you if i need any further information, i couldn't find an email sorry, could i get a guide as to how to get access to this area? (the ones in the picture) i've taken the screen out of the imac, peeled back the silver-metlish tape around the outside of the back, unscrewed the screws along the outside (6 in total i believe) but from there i am stuck how to get to where your pictures illistrate. I would gladly even donate as this methon should save me buying a £30 soldering iron to do the other way i see further up

much apreciated

Stew Foreli