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I would like to diagnose the iMac 2011 which I got from a friend. The iMac seems to be working as I hear the chime at startup. The display appear to be black. I did the following: Checked display in a dark room : - nothingShine a light to the display :- no pictureChecked inverter of the LCD with voltmeter “: work fine Now from here there are different possibilities as follows: Broken LVDS connector at the logic boardBroken LED strip inside LCDBad LVDS connector cableGod know what exactly So I want to begin with LVDS connector at the logic board. Where can I find the schematic of output pins and corresponding volts LVDS sends out to LVDS cable? Can this be checked with volt meter when iMac is on?
First is to know the history on this model. Check on the bottom of your stand and see if your machines serial number ends in one of these: DHJQ, DHJW, DL8Q, DNGH, DNJ9, or DMW8 DPM1, DPM2, DPNV, DNY0, DRVP, DY6F, F610If so your problem most likely will be a defective GPU.Hook it up to an external monitor to confirm.
