A communication apparatus comprising a system unit and a near-field communication unit, wherein said system unit includes: an operation history detection unit configured to generate operation history information of said communication apparatus; an error detection unit configured to detect a malfunction of said system unit and generate error detection information about the malfunction; a first storage unit configured to store the operation history information; and a system control unit configured to control said communication apparatus; said near-field communication unit includes: an antenna unit configured to receive a radiowave from an external reader-writer apparatus; a communication control unit configured to perform near-field communication with the reader-writer apparatus through said antenna unit; a second storage unit configured to store identification information for identifying said communication apparatus, said second storage unit being readable by the reader-writer apparatus; wherein said communication control unit is configured to transmit the identification information, the operation history information, and the error detection information stored in said second storage unit to the reader-writer apparatus through the near-field communication, in accordance with a request from the reader-writer apparatus, characterized in that the communication apparatus further comprises: a first power source unit configured to supply power to said system unit and said near-field communication unit, a second power source unit configured to generate power by rectifying the radiowave received from the reader-writer apparatus through said antenna unit; and a power source switching unit configured to select one of said first power source unit and said second power source unit, and supply power from the selected one of said power source units to said near-field communication unit; wherein said power source switching unit is configured to select said first power source unit and said system control unit is configured to store, in said second storage unit, the error detection information and at least a part of the operation history information stored in said first storage unit, when said error detection unit detects a malfunction of said system unit. an operation history detection unit configured to generate operation history information of said communication apparatus; an error detection unit configured to detect a malfunction of said system unit and generate error detection information about the malfunction; a first storage unit configured to store the operation history information; and a system control unit configured to control said communication apparatus; said near-field communication unit includes: an antenna unit configured to receive a radiowave from an external reader-writer apparatus; a communication control unit configured to perform near-field communication with the reader-writer apparatus through said antenna unit; a second storage unit configured to store identification information for identifying said communication apparatus, said second storage unit being readable by the reader-writer apparatus; an antenna unit configured to receive a radiowave from an external reader-writer apparatus; a communication control unit configured to perform near-field communication with the reader-writer apparatus through said antenna unit; a second storage unit configured to store identification information for identifying said communication apparatus, said second storage unit being readable by the reader-writer apparatus; wherein said communication control unit is configured to transmit the identification information, the operation history information, and the error detection information stored in said second storage unit to the reader-writer apparatus through the near-field communication, in accordance with a request from the reader-writer apparatus, characterized in that the communication apparatus further comprises: a first power source unit configured to supply power to said system unit and said near-field communication unit, a second power source unit configured to generate power by rectifying the radiowave received from the reader-writer apparatus through said antenna unit; and a power source switching unit configured to select one of said first power source unit and said second power source unit, and supply power from the selected one of said power source units to said near-field communication unit; a first power source unit configured to supply power to said system unit and said near-field communication unit, a second power source unit configured to generate power by rectifying the radiowave received from the reader-writer apparatus through said antenna unit; and a power source switching unit configured to select one of said first power source unit and said second power source unit, and supply power from the selected one of said power source units to said near-field communication unit; wherein said power source switching unit is configured to select said first power source unit and said system control unit is configured to store, in said second storage unit, the error detection information and at least a part of the operation history information stored in said first storage unit, when said error detection unit detects a malfunction of said system unit.