Help Galaxy S3 white screen

[Gals3sam]

I have a problem with my s3. One day, I turned on the phone but white screen came up. I can only access to the download mode and I tried to root it but it failed. It says it needs the PIT file. I added the PIT file 16 Gb but still it fails. I can only access to the download mode.
A picture of the screen in this link: https://www.dropbox.com/s/ewvdk38to5hkbvn/Photo on 1-29-15 at 3.01 AM.jpg?dl=0

 

[Mikestony]

Howdy!
What carrier are you on? What method of root are you using?
I would suggest getting the firmware for your device and carrier from sammobile.com and flashing the firmware via ODIN.
As long as you can get into download mode, that's a good thing