Chosen Solution
I have a macbook pro mid 2012 15’’ with the black screen issue (I have video as I can use flashlight to login and then can use external monitor but no backlight on the original screen) I ran some tests on the logic board which seems fine till the moment. But I coulnd’t ran the full tests as I am not willing to take out the logic board and ran tests on the bottom side. I cannot find a friend with the same exact macbook pro model so as to make the simple test of getting the lvds cable connector out my logicboard and connecting it to his so as to quickly tell if the problem is on my logicboard or my screen. But a friend of mine have the 15’’ from 2015 which is retina (mine is not). Can this test still be performed? Or are the connectors different and I put in risk his computer?
If I understand you here your external monitor is working without any problems. So that leaves the issue as being something within the internal display. Lets see if we can diagnose this using a flashlight! Start up your system (everything connected internally) and then shine your flashlight into the lids logo (a poor mans backlight). Are you able to see the faint images of your desktop icons? If you are you don’t have a display issue but a backlight issue which might be a simple fix on the logic board. As for your direct question of fitting a retina screen onto your older MacBook Pro system, sadly the answer is No. The screens are very different, think of it this way your cars engine is dead so you put into it Formula 5 race car engine in! Not really practical is it? ;-} Update (12/23/2016) Yikes, thats unbelievable markup! I think you’ve already done it here. If you don’t feel you trust your self how about measuring the backlight power lines on the retina it will be the same as a comparison. I would use some sewing pins for the probes as it’s so tight to poke around the connector. Basically I solder a wire onto the pin and then clip my meter to the leads I created. I also put some heat shrink tubing over the solder joint and partway down the pin so I can’t short across another pin or component.
