Oh good call. Yeah the info button manually turns on and off the settings, but if you're in live view you should still see an image even if the display is turned off.
Also, my t2i has a proximity sensor for the viewfinder, and I'm guessing from what I've seen of the t4i that Canon didn't abandon that feature.
So if those two buttons don't fix the issue maybe there's something wrong with that sensor on the camera?