iMac 27" from 2012. Screen defective, but boots normally and remote screen works.

[rin67630]

I have here an iMac 27" from 2012, which suddenly started with a black screen with faint vertically blurry bars.
It appears to boot normally and can be remotely accessed either on remote screen and disk resources sharing.

Am I right in the assumption that the graphic card is OK?
Are the described symptoms those of a defective screen or mere a cable issue?
If it were the latest, does a replacement exist to buy?

Thank you for sharing your experience.
Regards

 

[paardenkapper]

Can you provide some photos to show the blurry lines on the internal screen?
As long as the image on an external screen is flawless the graphics card is working fine.

You could be lucky finding a working replacement screen on eBay or so but they tend to develop yellowish corners over time. Maybe pick up a complete iMac listed as broken/for parts which just has minor quirks.

 

[rin67630]

Can you provide some photos to show the blurry lines on the internal screen?
As long as the image on an external screen is flawless the graphics card is working fine.

You could be lucky finding a working replacement screen on eBay or so but they tend to develop yellowish corners over time. Maybe pick up a complete iMac listed as broken/for parts which just has minor quirks.

i will have to wait for this evening since the lines (in fact finger broad strips) are quite weak.
I did not yet test with an external monitor, just with remote screen.

 

[rin67630]

I have here an iMac 27" from 2012, which suddenly started with a black screen with faint vertically blurry bars.
It appears to boot normally and can be remotely accessed either on remote screen and disk resources sharing.

Am I right in the assumption that the graphic card is OK?
Are the described symptoms those of a defective screen or mere a cable issue?
If it were the latest, does a replacement exist to buy?

Thank you for sharing your experience.
Regards

I have now connected an external screen.
On Windows the internal monitor is shown as a tiny 1024*768 monitor (the default when the EDID can't be read)
The result is clear: the graphics are OK. The problem is either the panel, or the connection between the panel and the graphics card.
I will have to open that box, hoping of just a connection problem.

 

[paardenkapper]

It's rather unlikely that the connector jiggled itself loose but it not completely unlikely.
But an external display works fine, I assume?

Maybe you can find a cheap iMac with a broken glass panel yet working display these tend to be quite cheap.

 

[rin67630]

Maybe you can find a cheap iMac with a broken glass panel yet working display these tend to be quite cheap.

Aren't the glass front and the display one single unit on the iMac 2012?

 

[Nguyen Duc Hieu]

Aren't the glass front and the display one single unit on the iMac 2012?

Yes they are.