IMAGE FORMING APPARATUS AND ABNORMALITY DETERMINATION DEVICE

An image forming apparatus includes an image former, a toner bottle holder, a bottle cover, a lock mechanism, a drive mechanism, an abnormality detector, a cover opening-and-closing detection sensor, and processing circuitry. The lock mechanism locks the bottle cover at a position at which the bottle cover covers an insertion port of the toner bottle holder. The drive mechanism drives the lock mechanism to release a locked state of the bottle cover. The abnormality detector generates an abnormality detection signal when the abnormality detector detects an abnormality of the drive mechanism. The cover opening-and-closing detection sensor detects an open state and a closed state of the bottle cover and generates a cover opening-and-closing detection signal indicating the open state or the closed state of the bottle cover. The processing circuitry determines an abnormal part of the drive mechanism based on the abnormality detection signal and the cover opening-and-closing detection signal.