Image forming apparatus

Abstract

An image forming apparatus includes a processing unit, a sensor, and a processor. The processing unit has a developing device using a developer containing two components of a toner and a carrier. The sensor outputs a detection value corresponding to a toner concentration of the developer during operation of the processing unit. The processor performs a process of determining whether a service call to a service person is necessary based on the detection value of the sensor. The processor operates the processing unit at either a high process speed or a low process speed to acquire the detection value of the sensor, before determining whether the service call is necessary. The processor determines the process speed at which the processing unit is to be operated based on the detection value. The processor operates the processing unit at the determined process speed to determine whether the service call is necessary.

Dependencies are inferred from the claim text.