IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To provide an image forming apparatus for recovering efficient color reproducibility by performing diagnosis including detection of a color-mixture state of toner in a developing device for the apparatus in a self-diagnosis mode. SOLUTION: The apparatus, having the developing device for storing toner of different colors, forming toner images in the different colors on an image supporting body, and transferring the toner images with the different colors in turn on a transferring medium, recovering remaining toner on the image supporting body after transferring and supplying the recovered toner to the developing device to recycle it, has a control part for controlling actions of the apparatus. The control part begins the self-diagnostics mode by an interrupt signal, and the the self-diagnosis mode performs the diagnosis including the detection of the color-mixture state of the toner in the developing device for the apparatus. In the self-diagnosis mode, it becomes possible to efficiently recover the color reproducibility by performing the diagnosis including the detection of the color-mixture state of the toner in the developing device for the apparatus. COPYRIGHT: (C)2004,JPO