Chosen Solution
Dear Ifixit team, My 2010 iMac does not power up the display. I’ve checked the ribbon cable and connectors. Everything is fine. I’ve measured the signals to the display. It seems that there is no video signal. There is no boot fault sound. The iMac is working except the display, it’s working on the external display like a charm. I’ll appreciate any solution, advice, schematic and etc. Thanks in advance! Kind regards!
If an external monitor is working that nails it down to the internal display and its connections and the backlight logic. With everything connected using a flashlight pressed on the screen at a sharp angle are you able to see the faint image of your desktop and the icons on it? If you are your backlight cables & logic needs to be checked out. If you don’t see anything in a darker room restart the system to you see a quick faint glow during the boot up (sometimes you might not see it)? If you do then the sync cable is bad. Otherwise the display its self likely needs to be replaced. Did you bang or drop the system?
“Video card” is live because external screen works. Should be back light problems. Can you give me you logic board model?
Just a dead lcd on the main display. The fact that you are able to view on a separate display means your video card / motherboard are working fine. Just need to replace the main lcd. no need to over complicate it :)
