Persistent horizontal lines appear on iMac screen

The same issue just suddenly happened to my iMac M1. I bought it in August 2021, and now after 3 years it just happened. No external physical damage at all. I’m kinda frustrated right now, not willing to pay somewhat $600 for the screen repairing since it’s clearly not my fault. Should I buy the new iMac M4? I’m so worried cause I don’t know if it will happen again. Apple should really do something about this.

Andre_marc92 I subscribe 100% what you wrote. Forced by this incredible circumstance I purchased a Mini M4 and I'm going for a 27" reliable and quality grade monitor. Of course I added AppleCare (I owned several Macs since long time and I never felt the need, but now...)

YES Apple should

Having the same issue. Mine started after I updated to Sequoia directly from Ventura and checked out the new live/dynamic screensavers/wallpapers from Apple. My machine froze and the lines appeared after I rebooted.

I don't want a new machine from Apple. I want to make sure my existing machine doesn't degrade further. Any advice is welcome. It may help M1 iMac users who haven't encountered this issue yet avoid it.

Is the consensus here that the iMac display will progressively worsen as I keep using it? I can live with a few lines at the bottom of my display. Right now it is not too distracting to me. But from what I've read the lines grow with time.

Yeah, I have been thinking about the same thing. I am thinking of going the Mac Mini route as well. At this point, I don't know if the same issue won't happen after 2-3 years of owning an M4 iMac. That risk, at least for me, is a bit much

Ro_cos

I subscribe what you wrote. I followed that option you mentioned: day after the disaster I ordered a fresh new Mini M4 in order to keep on working with Mac. Expensive unespected and disappointing workaround

Hi everyone.Also appearing lines to my iMac (in Spain). I have just written on the Apple Community Spain, where there was another customer who just wrote about....so could be an issue that may grow in numbers soon.

Horizontal Line Issue Leads to Overheating and Display Damage in 2021 iMac M1 Chip - Seeking Resolution

I'm reaching out for advice and support regarding a serious issue with my 2021 iMac M1, which I believe is linked to a known manufacturing defect involving horizontal lines on the screen. Here's a detailed account of what's happened:

Timeline:

May 2024: I first encountered horizontal lines on my iMac's screen. I took it to an Apple Service Center in India for inspection. 

Service Details: 

Inspection Fee: I paid for the inspection Fee of 2500 INR, but the cost for a screen replacement was quoted at a price I couldn't afford.

Assurances: I was assured by both the service center manager and an Apple senior executive that these lines were not a cause for concern and would not lead to hardware failure. The service service center manager said I could continue using the iMac for years if the lines weren't disturbing my work.

January 15, 2025: The situation escalated dramatically:

Display Anomaly: Suddenly, the horizontal lines at the bottom half of the screen cleared and moved upwards, which was a new development.

Overheating: Heat started emanating from the top right corner of the iMac, to the extent that it felt like it was burning. 

Immediate Action: I turned off the device as soon as I noticed this overheating.

Damage: The extreme heat has caused visible damage to the display, with dark spots and black areas appearing on the screen. The top right area, where the heat was concentrated, seems particularly affected.

Service for VMI Report: During the Visual Mechanical Inspection for the report, the technician used the device for about half an hour, potentially causing more internal damage.

Current State:

VMI Report: The report indicates no physical damage, suggesting this overheating might be related to the same manufacturing issue that caused the lines.

Safety and Functionality: The device now poses a fire risk due to overheating and has functional issues due to the damaged display pixels.

Request for Help:

I'm aware that many users with 2021 iMacs have reported similar issues with horizontal lines, suggesting this is not an isolated case but a manufacturing defect.

I'm seeking advice on how to get Apple to make an exception for repair or replacement, given:

The known defect.

The assurances given by Apple representatives which led to this safety and functionality issue.

The fact that I already paid for an inspection that did not foresee this outcome.

Has anyone here had success in getting Apple to address similar issues post-warranty or been granted an exception for repair/replacement?

Any advice on how to proceed with Apple Support in the USA, given the Indian team did not resolve this adequately?

Additional Information:

I have documentation including the VMI report, service history, and forum discussions about this defect.

Thank you for any insights or support you can offer. I'm keen on resolving this safely and ensuring my iMac doesn't pose a hazard to my family.

Best regards,

Karthick

You’re not entitled to any refunds for post-warranty service, unfortunately. Furthermore, unverifiable opinions/assurances volunteered verbally at the time were good faith, friendly advice based on the inspection then, not official recommendations on how to proceed or provide guarantees that the machine would not deteriorate further.

Apple will be in touch with you if their position changes, which is unlikely since the issues did not crop up during the warranty period. Not to mention subsequent deterioration of your machine to a “fire hazard” condition which suggests an operating environment unique to yours.

My advice to you would be to discontinue using your Mac and storing it away in the remote chance that Apple contacts you. Then buy new, Apple or non-Apple whatever suits you best

Bottom line: It is what it is and if it isn’t any longer, Apple will contact you directly. Ranting on this forum with unverifiable one-sided narratives achieves absolutely nothing. All the best!

@Universall I'm sorry that you are going through this. I'm from India as well and I'm having the same problem (very early stages, not as bad as yours). What is the latest update you got from Apple Support India on this? Based on the pics you've shared, the overheating issue on your display seems to be much severe than others' I've seen on this thread.

I am also suddenly experiencing the same problem with my 2021 M1 iMac. The only course of action is to hope it's added to the "Apple Service Programs" which doesn't seem likely if it hasn't already happened.

It also happened to me today. I can't accept it—only three years, and it shouldn't be what Apple stands for in terms of good quality. I hope Apple can provide a free repair or recall the affected products.

One of these two iMacs cannot be turned on today. Not sure if this is due to the worsening of the short circuit. Yesterday, I connected to an external monitor and it worked fine. Turn off the iMac overnight, then it is no longer turning on starting this morning. So frustrating.

Thank you for sharing some good news, although I would not "sincerely thank" Apple until it is under the official Service Program. If the design and material is being the same, it is likely going to happen again in the next +24 months.