Diagnose Display or Video problem?
iMac Intel 27" A1312 EMC 2374 i7
iMac powers on and chime sounds, the display can be seen to power on and remains black the entire time, checked with flashlight and nothing is seen.
All of the LED's are lit, I can connect to the unit remotely and share the screen, I checked the system profiler and find that the video card is detected. I find that if I go to the display preferences and adjust the screen brightness you can see the backlight adjust as its supposed to.
I tried reset all settings
I tried re-seating the video card
I tried swapping backlight inverter and LCD with Known good hardware same result
video card is my last step but i just wanted any suggestions before i shell out the cash
connect it to a tv and see if you have fully working unit.
if so it is either a fried video graphic part. look it up on ebay they sell them on there because they have a ISSUE with that happening. i would take it to A APPLE STORE AND LET A GENUIS BAR WIZARD TRY AND fix it for free, he might have a used part he will give you. and there you will get a forsure diagnosis
There is a Quality Program with regards to this model year. However, a test has to be completed by a technician in order to validate the machine. There are two different cards for this model. Only the one card is affected. Did you try external video to see if its in fact the card?