A wireless diagnostic module includes a connection port connected to a connector provided in a first appliance; a first signal transceiving unit to transceive a signal corresponding to a first communication protocol by making communication with the first appliance connected through the connection port; a signal converting unit to convert the signal corresponding to the first communication protocol transmitted through the first signal transceiving unit into a signal corresponding to a second communication protocol; and a second signal transceiving unit to transmit the signal corresponding to the second communication protocol, which is converted through the signal converting unit, to a second appliance, wherein the first communication protocol comprises at least one of ISO, KWP, PWM, CAN and VWP supported by the connector provided in the first appliance, and the second communication protocol comprises a wireless communication protocol for wireless communication between the first and second appliances.