The basic principle of TPMS (Tire Pressure Monitoring System): Installing a sensor on the tire hub or tire valve, in the sensor included the electricity bridge type electronic air pressure induction device that can induct the air pressure, it can transfer the air pressure signal to electricity signal, and then send it out through wireless electropult device. After that the air pressure information which is sent by sensor is transacted by the receiver, it will be showed on the display which is installed on the driving console, and it will be actually monitored under driving process. Just from the monitor, the driver can see the air pressure and temperature of every tire clearly. When the air pressure and temperature is different from the appointed standard value, the monitor will alarm automatically. Accordingly the driver can treat with the exceptional conditions in time and avoid the accident from happening