Before you do anything else, use the menu system to reset the camera to factory default. If necessary look through the viewfinder to do so if you can't see the LCD display.
After doing that, make sure the lens cap is off, set the camera on P mode, looking through the optical viewfinder, take a photo. Use the review button to check the imager and then use the INFO button to cycle through the display and see what you get. If nothing is displayed in review then the sensor is dead or the LCD display is malfunctioning. If it is the latter you could still use the camera by just using the viewfinder but if it is the sensor, then the camera will cost more than it is worth to repair.
cheers, TREVOR
"The Amount of Misery expands to fill the space available"
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris
