Persistent horizontal lines appear on iMac screen

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.

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.

"They charged ne 30USD for inspection"

Who exactly is "they"? In the US, the Apple in-store diagnostic is certainly free; I've taken advantage of that twice in the last six months.

If there is a "consumer product protection" agency in your country. I suggest you file a complain. Please post the final results of that here if you choose to do so ... if you can file such a complaint of course.

Considering the millions of Apple Macs worldwide, the number of complains here is an exceedingly small percentage of the whole. Problems happen for sure, but just because it happens to you does not mean it happens to many. That's known as a "hasty generalization".

latVm wrote:

Lol free diagnostic? They charged ne 30USD for inspection

Where are you located? as stumpy1946 pointed out in the US at the Apple Genius Bar the diagnostic is free. If you go to an Apple Authorized Service Provider they may charge you for the diagnostics but wave it if you have the repairs done there.

I am having the same problem. I've had this iMac less than two years. These lines appeared a couple weeks ago and have shifted a bit but haven't disappeared. From what I'm seeing online, we are not the only ones experiencing this. This is not right. Apple should be held accountable for this issue.

[Edited by Moderator]

I've been to the Apple Store in Shanghai and the repair fee without Apple Care is about RMB 4,891 which is even more than the recycle fee lol. They said that the solution could only be screen replacement and they have no idea why the problem came out. Cuz there are so many user suffering the same problem I wonder if Apple should be responsible for this problem.

Took it to Apple Store today, I was offered screen replacement for $648 plus tax, which would be $690.93. I am thoroughly disgusted. I will look into filing a complaint with the state division of consumer affairs.

I was told to bear the repair cost 100%. After a few months of lines appearing and flickering, my screen has turned completely blank!

This is just the beginning. My iMac M1 started with some lines below, slowly filled up over the span of few months and eventually a black screen. If the problem is the quality of the product, a replacement will give you the problem again. Why are we bearing the cost of a product that is below par?

I am having the same issue, just today this horizontal line suddenly appeared out of nowhere

Update: The horizontal black line disappeared, turned it off for a few days after but when I turned it on it was still there, a few hours after, I thought it disappeared by itself, but it just moved to the left part of my screen and became a vertical yellow line. Starting from where the horizontal line appeared the last time down to the bottom. Up to now, the vertical line is still there. It's unnoticeable, better than the irritating horizontal black line.

Have you blown the dust out of the intakes lately?

What temperatures does this App report? Especially the GPU.

This App can be used to speed up the fans, all my iMacs would be dead without it.

Never ever ever drop fan speeds below the speed that the Mac itself is calling for.

MacFansControl…

https://www.crystalidea.com/macs-fan-control