Idiom
go blank
1.
to become unconscious.
He remembers trying to get up, and then he went blank until he woke up the next morning with a roaring headache.
Usage notes: sometimes used in the form everything went blank - someone became unconscious:
I heard a noise behind me, and then everything went blank.
2.
to stop receiving a television picture.
There was a popping sound, and then the TV screen went blank.
3.
to forget.
He let his mind go blank and kept on walking, thinking about nothing at all.