Image forming apparatus with processing unit to control cooling fan operation

An image forming apparatus operable in a first mode and in a second mode, the image forming apparatus comprising:

• a power source device configured to convert an AC voltage of a primary side to a DC voltage and supply to a load of a secondary side, the power source device being operable in (i) a first output mode in which the image forming apparatus is in the first mode and (ii) a second output mode in which the image forming apparatus is the second mode, wherein the power source is configured to output a first DC voltage in the first output mode and is configured to output a second DC voltage lower than the first DC voltage in the second output mode;
• a cooling fan configured to cool the power source device;
• a temperature detector disposed at the secondary side of the power source device and configured to detect a temperature of the power source device;
• a processing unit configured to control the cooling fan based on a detecting result of the temperature detector, the processing unit being capable of switching the power source device between the first output mode and the second output mode;
• and
• a signal output circuit configured to output a signal to the processing unit when the temperature detected by the temperature detector is equal to a predetermined temperature or higher,
• wherein the processing unit includes a port capable of detecting the signal output from the signal output circuit in the second mode,
• wherein the cooling fan is operable at the first DC voltage, and
• wherein, in a case where the signal is inputted to the port from the signal output circuit in the second mode, the processing unit controls to switch the power source device from the second output mode to the first output mode and controls to operate the cooling fan to cool the power source device.