MacBook Pro does not boot, backlight on
Since last monday, my barely 3 y/o Macbook Pro Retina 13" (Late 2013) does not boot anymore. It happend all of a sudden and without any previous event (spilling liquids, dropping it etc...).
Pressing the power button, the keyboard backlight + display backlight work, but the screen remains black. If I close the Macbook, the backlight stays on (the Apple Logo on the back still glows). It stays frozen like that for around 10-15 minutes, then it shuts down. Right after that, if I hit the power button again, nothing happens. But waiting for 20 minutes, it's possible to repeat the procedure.
If I connect an external monitor via VGA + Thunderbolt adapter, the 2nd screen shows the Apple Logo and the loading bar, but afterwards the it also stays black.
The keyboard should work, at least the caps lock light does. The Macbook was running with the latest macOS Sierra.
I already tried the SMC and PPRAM reset, which did not work. Booting in recovery did not work either. I also tried entering the password and trying to log in, hoping the external monitor would then show the desktop, which did not happen.
At the Apple store I was told to replace the display. But if only the screen is broken, why is it not possible for example to log in and work on the external monitor?
I hope someone of you has an idea, thanks already in advance!