A method of diagnosing an electronic display device (1) having a screen (3) and a graphics memory (2) in which image data (14), of an image displayed or to be displayed on the screen (3), are one of stored or changed. A measured value (15) characterizes a current consumption or the change in current consumption of the screen (3) or display device (1) while a reference value (16) characterizes the current consumption or the change in current consumption of the screen (3) or display device (1) on the basis of the image data (14) or the change in image data (14). The method compares the reference value (16) to the measured value (15) to determine any malfunction or error in the electronic display device (1).