Screen replaced, vertical block on LCD, external display works
I broke the LCD of my mid-2011 27" iMac while we were moving apartments. The LCD was beyond repair, but when I connected the computer to an external Dell display (via a mini displayport->VGA adapter plugged into a Thunderbolt port), there were no issues outputting to that display. So it seemed that only the LCD needed to be replaced.
I replaced both the LCD and the LCD cable (the ribbon cable with the ZIF connector). Now, the display works without distortion except for a large vertical block that takes up 10-15% of the screen:
The vertical block is not always the same colors: sometimes as above it's a gray block, other times it consists of multicolored lines. But it's always in the same location on the screen.
I'm trying to diagnose the issue. The screen is a new replacement part, but maybe it is faulty? The fact that the external display has no issues makes me think it's not a video card issue. Are there other tests I should do? I have checked that the ZIF connector is seated properly, and it appears to be.
Questa è una buona domanda?
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Hello, I'm in the middle of replacing my lcd screen too, A1312 emc 2429 27" 2011 iMac, Unfortunately the screen I ordered has only LED backlight cable attached. Do you know what are the other cables I will need? I threw out the old screen without thinking about those cables.
da Django Chained