I have an Imac that appeared to have a bad screen. I changed out the screen and still no video. I can plug an external monitor up to the thunderbolt port and get video on an external monitor fine. Any suggestions?
It is a late model IMac with 27 inch 4k retina display. Not sure about whether LCD or LED, I would also assume LCD. Everything is connected and appears to be seated well. The screen never lights up or shows any backlight. However, an external monitor works just fine. Im wondering if one of the connections on the board has failed.
Also, I am assuming "screen" meant the glass piece. If you replaced the entire unit, that would include the parts I mentioned. Sorry for my own confusion
So yes, look at the connection points on the mainboard.