Image forming apparatus, replacement developing component, and method for controlling image forming apparatus

A method for controlling an image forming apparatus that includes

• an accommodating portion in which a replacement developing component which is fitted with a rotary member including an operating member and which stores toner is fitted,
• a motor which rotates the rotary member on the replacement developing component fitted in the accommodating portion, and
• a development sensor,
• the method comprising:
• fitting a new replacement developing component;
• configuring the operating member not to be in contact with the development sensor before the motor rotates the rotary member,
• rotating the motor to move the operating member on the rotary member to bring the operating member into contact with the development sensor;
• making the development sensor output a first level when the development sensor is in contact with the operating member,
• making the development sensor output a second level when the development sensor is not in contact with the operating member;
• and
• receiving an output of the development sensor to judge, based on output levels of the development sensor at a first time point before the motor rotates and at a second time point after the motor rotates, whether the replacement developing component is fitted or not and whether a new replacement developing component is fitted or not.