Crashed and now only white light blinking I plugged an iPhone into my MacBook Pro with iTunes open. After a moment, my MacBook got stuck and shut down by itself. Then, I tried to open the MacBook Pro again. But, nothing is happening except few things like the white light is blinking and fan is running. I tried a couple of times; nothing happens. How can I fix it? What is the problem?
Have you tried holding down the power button until the light goes out completely (10 seconds or longer)?  Then push the power button again and see if it boots.

You can try to reset the NVRAM (holding down CommandOption P and R at boot-up) and the SMC (if NVRAM doesn't work).

See https://support.apple.com/en-us/HT204063 and https://support.apple.com/en-us/HT201295.