Persistent horizontal lines appear on iMac screen

Keeping contact apple feedback with the info below: (i do it once a week now)

Product Feedback - Apple

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.

You also from Singapore too? My is M3 iMac , last weekend as per normal I wake up the iMac from sleep and noticed the lines at the bottom.... I search around is it Only I ? encounter this but who knows see this In Apple Community even at Mac Rumours forum even on establish Tech website, Review etc all claim the problem start from M1 later M2 now M3 users also report the Same issue regarding lines Suddenly appear just Only use the iMac for literally one year or so. This is unacceptable. I do own iMac intel even till now still ok. So any update ? How? You still continue use? Or?

It will get worse.

Mine got a few lines first, and then more lines, and after like 3 weeks it completely blacked out.

Like the others, the bottom-left handed side of got super hot and there's a burn mark there.

I've talked to the support 3 times already. The last time I raised this overheating issue to their supervisor and she told me that I have to pay full price for repair and won't give any free of charge repair exception. She also told me that I have to stop using my iMac now (but without giving me any other solution except a full-price repair) and they will not bear any responsibility if anything happend as she has warned me.

I'm so frustrated with the serice Apple is providing given the premium price I'm paying.

Writing in this user forum is not the way to inform Apple of this. You need to call Apple Support directly. They log all your calls and you can ask for the technician to note your issue and concerns. All you guys doing here in the forum will not help you to get the service you need. Call their support number.

I just became another apple client with the same iMac flickering display issues. I’m from New Jersey and 2 days ago I noticed disruptive flickering horizontal lines at the bottom of my iMac M1 24” display that won’t go away. Tried every possible thing including turning off for a few minutes and back on, running diagnostics, disk repair aid, changing resolution, brightness… nothing worked. Finally decided to get in touch with apple via chat, and was advised to visit an Apple Store. So I did today and after running all diagnostic tools they had I was advised to change the screen for meres $650! After visiting this community, I realized I am not alone. On the contrary, there are a lot of people throughout the world with the same issue.

so I decided to follow the advices offered here in this forum.

Contacted apple once again via chat and requested to speak with a senior advisor. She called me right away, but no solution was offered for my problem other than paying for service or connecting another display to the computer.

I am sad and disappointed with apple. They know it’s a manufacturing defect that is happening frequently with this product.

But I don’t want to feel defeated yet. I would like to know if anyone knows an email address or a website where I can tell my story and be one more voice advocating for consumer rights. Maybe we can get a recall program in place or if I am lucky and be one of the exceptions that gets extended warranty and fix the problem at no cost for me.

please help me getting this message across to someone at apple that can make things happen. Thank you

It's a costly fix for a problem that only occurred due to a faulty bit of design/engineering from Apple.

Even if we did do the display replacement it won't be a permanent fix as the same problem will come back eventually. It happened to me.

And since the iMac is somewhat of a niche product Apple will employ it's tried and tested formula; Ignore the complaints until we go away. Eventually Apple may even offer an 'acknowledgement' of this issue and engineer a more robust hardware solution for future iMac models but it will count jack-squat for those of us affected with our current machines.

And as for long time iMac users like myself, I will have to think long and hard before purchasing another iMac (which I prob won't) or even purchasing another Apple product.

I'm in Brazil, and I have a 2021 iMac M1 that started showing horizontal lines in the lower left corner of the screen two days ago. Today, these lines, which were light gray, have become thick black lines and are flashing across the entire lower corner of the screen. One black line remains permanently visible, and the others flash every 1 or 2 seconds. I've already contacted customer service, and they suggested replacing the screen for R$ 6600.00. I've tried mirroring the screen, and the problem doesn't occur on my iPad. I've tried restarting, turning it off, and unplugging the power cord, but nothing solves the problem. I have more photos and videos of the problem if needed.

Do what hcsitas suggested: report the issue to Apple frequently and take it in for a free diagnostic check. That will confirm that it's a hardware problem and you can then go from there.

Hou have to make an official complain at the Apple.com website

Thrue, but it is an strange problem that so many M1 users have the same issues. It looks to me that Apple has made a poor series of lcd screens…

Did you leave feedback on the Apple website about this? Link below:

Feedback - iMac - Apple

Hope with all the feedback they will start a repair program.

Hello, Could you check where your model was manufactured? You can check under the base/foot/stand, there should be a label that says 'made in' or 'assembled in'

It was on the mode of automatic adjustment of brightness. The context surrounding my iMac had always been not bright

its most likely a GPU/logic board issue OR display issue you can find out more by looking at this: Diagnose problems on Mac - Apple Support

For post-warranty issues, there’s AppleCare Products - Mac - Apple. Too bad you didn’t sign up. Nonetheless, use Feedback - iMac - Apple to vent. But before doing so, schedule in-store Apple Repair for a free diagnosis and repair estimate.

All the best.