Persistent horizontal lines appear on iMac screen

I am reaching out to share an ongoing issue I, along with several other users, have been experiencing with our iMac 24-inch models, and to seek a collective resolution.


Problem Description:

  • Persistent horizontal lines appear on the screen, which significantly hampers the usability and visual appeal of the device.
  • This problem arises without any physical damage, and despite the stationary nature of the device.


Steps Taken:

  • Connected to an external display: The external display works fine, indicating the issue is with the iMac's internal display.
  • Reinstalled the OS: The problem persisted post reinstallation.
  • Avoided operating the iMac for a week: No change in the situation.


Concerns:

  • The cost of screen replacement is high, and there's no assurance that it will resolve the issue permanently.
  • The quality concern is alarming especially for a brand that positions itself as a premium segment player.
  • The support received thus far has been unsatisfactory, with no definitive solutions provided apart from a costly screen replacement suggestion.





Please do not ask us to visit to service center and replace the screen for 650USD + , problem happens mostly after warranty.


[Edited by Moderator]

iMac (M1, 2021)

Posted on Oct 21, 2023 10:40 AM

Reply
Question marked as Top-ranking reply

Posted on Jul 10, 2025 3:32 AM

UPDATE


I faced an overheating issue in the top right corner of my 2021 M1 iMac 24”, which eventually led to display failure with burn marks and a smoke smell after 2.5 years of usage. Initially, Apple India denied free repair as the device was out of warranty and offered only paid service. I escalated the case to Apple USA with proof that this was a known horizontal lines issue (widely reported in forums and media) and highlighted the severe safety threat to my family. After sharing high-resolution photos, videos, and diagnosis reports, and insisting on escalation to their engineering team, Apple granted me a one-time exception (CS Code) for a free display replacement. 🙏 After 90 days of usage with the new display, it is working completely fine, and I sincerely thank Apple for their credibility and for standing by their customers in critical situations.




Similar questions

524 replies

Aug 21, 2025 6:06 AM in response to latVm

Unfortunately my 2021 iMac is suddenly showing the grey horizontal lines too. So this is obviously a defective manufacturing issue that apple is well aware of. Lesson learned and I will not be replacing it with a new Mac or any other apple product for that matter. I was quoted an absurd amount to fix this out of warranty.


[Edited by Moderator]

Aug 25, 2025 8:01 AM in response to latVm

Hello Community,


Sorry for my bad English.


Since 2 Days I have these lines on the display too.

I chatted with Support and his answer was curious : I have to clean my screen. it is dust or something... REALLY ???


I have abt. 10 lines in black and regular 10 lines in white wich disappear every one second, then they come again.


iMAC 2021, M1, 16GB, 2TB SSD


Yours,


Wolle

Aug 26, 2025 1:14 AM in response to latVm

Mine started showing these multicolour lines in less than a year after purchasing it in July 2022. Sales people didn’t advise of any manufacturer service cover or anything like that. When I went to iStore they wanted to charge me over R36k to repair it - which was ridiculous to say the least. There is no way all users could be having the same issue and Apple doesn’t want to take accountability for this defects, after we spent so much money to purchase these devices. I need a personal laptop desperately, I don’t have money they need to fix it and I can’t just give it away because when I tried to trade it, they offered a fraction of what I spent to buy it - which is unacceptable. Can anyone advise what the best way is to resolve this, please?

Aug 26, 2025 8:12 AM in response to -g

Absolutely ! In the years I owned 2 iMacs plus 2 mini and 2 MacBooks but now I say I'll never purchase an iMac again ! Yes It may happen such kind of fault (even if I never happened to me in the past) but the worst thing in my opinion is feeling abandoned. When my iMac 24" M1 showed the fault I had to purchase a new mini (November 2024) and a new monitor (I had some work in progress) for a problem I didn't cause.

Aug 26, 2025 4:04 PM in response to Giorgio_BXN

iMac Feedback was no help to me. I was even told that someone would get back to me with a solution! That never happened. I love Apple products. I have been using all of them for years. This issue with a computer that was barely one year old is extremely disappointing. Apple MUST come up with a solution, as it seems to affect thousands of users. Come on, Apple. I mean, come on.

Sep 9, 2025 10:24 AM in response to latVm

Hi Apple Community,

As a loyal Apple user for 15+ years from Colombia, my family and team have always chosen Apple for our computers, iPads, iPhones, and Apple Watches. We deeply appreciate Apple's exceptional quality and customer service.

The Issue: I'm experiencing persistent horizontal lines on my iMac 24" screen - a problem affecting thousands of users worldwide. The external display works perfectly, confirming it's an internal display issue.

Our Request: Given the widespread nature of this problem, we respectfully ask Apple to:

  • Investigate this as a potential manufacturing defect
  • Implement a quality policy for affected iMac 24" users
  • Offer complimentary repairs for documented cases

We've seen successful free repairs in this community, which gives us hope for a similar resolution.

We remain big Apple fans and trust in Apple's commitment to quality and customer satisfaction. This would be a great opportunity to demonstrate why Apple continues to lead in innovation and service.

Thank you for considering our request.

Best regards, A loyal Apple user from Colombia 🇨🇴



Sep 9, 2025 10:35 PM in response to latVm

I have a group of people (72) on Chinese social media who has this issue, still adding ... this is not a case to be ignore, please united to solve this problem together apple users!

It costs almost 5000yuan in China to replace the screen, even I choose to replace this, then I will be afraid this screen will have the same issue. Right?

How should we do this ? any heads up? an idea to reach the top and rise their awareness? and give us a good solution.

Persistent horizontal lines appear on iMac screen

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