Random black screen and difficulty to boot after a small fall
I dropped my 15″ MacBook Pro Retina mid-2012 from about 2 feet on the carpet while it was running. It felt flat on the screen side.
I closed it when I got it back from the ground and then I was unable to awake it.
The fall was so small that I didn't think one second it would damage the computer.
On the outside, there is absolutely no visible damage, the screen is ok.
I am unable to wake it up systematically. I have to try 20 times before the screen shows up, the other times, the screen remains black
(the backlight remains off, I can see no light on the apple on the reverse side of the screen) but the fans are working.
After a reset of the PRAM (Command + Option + P + R key, I can hear the second startup sound) and SMC (Shift+Ctrl+Option+power button), I can hear the boot chime but most of the time, the screen is black (totally off, no backlight)
I have to force the shut down (by a long press on the power key until the fan off) and try again until the screen shows up.
I figured out to run the diagnostics tool (boot with R key) and it shows no issues.
Sometime, when it boots, the screen turns off during the loading bar.
When it boots properly, it looks like everything is working fine. I could do a full TimeCapsule backup on a USB drive.
I can close the clamshell with the machine awake, it goes to sleep, when I open it again it works few times until completely off.
Anyway, when it is running properly, after a variable amount of times (1 min to 2 hours), it finally goes to black screen (screen off, no back light, fan on).
I went to an Apple authorized repair center, they opened it to check if the screen wire/socket was well fixed. It was ok.
They also tried to connect a monitor when the screen was black and the monitor was not working too.
They said that it is probably the motherboard (>500 euros) but I am not very sure about that as it looks like a bad connection of something.
I went back to my home and I bought the specific screwdriver to open it myself. Everything looks OK except one little magnet that was stick to the lower case.
I put a photo here: https://screenpresso.com/=1LP1c
I have put it back to its place but it looks like it was only there to hold the lower case. Can someone confirm ?
(is it the same as http://www.powerbookmedic.com/Macbook-Pr... ?) Do you think it can linked to the reed switch/hall sensor ?
The battery of the MBP works properly, there is no sign of failure on that side.
Somebody knows what is happening? Any clues ?
Thank you very much for your help!
Is this a good question?