Chosen Solution
Hello everyone, I have this iMac from 2011, and my LCD screen stays black after booting up. However, when I attach an external monitor, it does startup and work perfectly. The only thing is noticed was that the 4th diagnostic LED is not lighting up. You would think it’s the LCD panel right? Well, I’ve switched the screens with another iMac, and it works fine. So it is not the LCD panel. Then I’ve started switching other parts aswell, checking if something changes, or if any part is broken. The LED backlight board is fine, the cables are fine, the LCD panel is fine, it does get power and I assume the Logic Board is fine aswell because it does boot and work normally (even though it has a black screen). Does anyone have a clue why it does work on an external monitor, but the LCD just stays black? Please let me know!
Hey Stijn, sorry to hear about your screen! Have you looked as the sensor that tells the computer if the lid is shut or not? Thats the only thing I can think of. If the back-light is indeed getting powered then it should be working unless the screen is bad. Did you try testing the screen in a different computer or did you put in a new screen?
