Tire pressure monitoring system and method

The system has a tire pressure detecting device (10a) attached to tires of a vehicle for detecting tire pressure. Controller (13) controlling a tire deflation warning has an identification (ID) code registration section (S5) to register an ID code of each tire by updating data stored in a memory. The code registration section registers the ID code when a jack-up determination section determines that the vehicle is jacked up. A transmitting device (10d) transmits radio signals indicative of the detected tire pressure, where each signal corresponds to the ID code provided to each tire. A receiving device (13b) attached to a vehicle body side receives the radio signals from the transmitting device. An independent claim is also included for a tire pressure monitoring method.