First, the controller 100 causes the display device 473 to display a menu screen G1 shown in
The controller 100 decides whether the image forming apparatus 1 is in the maintenance mode (step S1). When the mode setter 102 has set the image forming apparatus 1 to the maintenance mode, the controller 100 decides that the image forming apparatus 1 is in the maintenance mode (YES at step S1).
For the purpose of the description, it will be assumed that a maintenance work, including replacing the ink tank unit 122, and connecting the connectors JF1 to JF4 attached to one end of the second pipes UP1 to UP4 of the ink supply device 123, to the connector receivers JM1 to JM4 of the ink tank unit 122, respectively, has been carried out by the user.