USB or Solar Charging Car TPMS Tire Pressure Monitoring System HD Digital LCD Display Auto Alarm tool Wireless 4 external Sensor Notice: Please push left button over 3 minitus to turn on monitor, if it does not work, please try again after charging. Specification: Solar power charging LCD displaying Adhere to windscreen for installation Operating frequency: 433.92Mhz 50KHz Operating voltage: 3.7-5 V Working temperature: -20 -75 Adhere to windscreen for installation Operating frequency: 433.92Mhz 50KHz Operating voltage: 3.7-5 V Working temperature: -20 -75 Parameter 1.Monitoring system body Operating voltage: 3.7-5V Storage temperature:-30C-90C working temperature:-30C-85C RF Emission frequency:433.92MH50KHz RF Signal sensitivity:-90dbm Display mode:LCD Color Bright screen current:6mA Black screen current:4mA Size:85*95MM Built-in Sensor Working Temperature:--40 C -125C Working Frequency:433.92MHZ working humidity:Max95% Tire monitoring range value:0bar-3.5bar Deviation0.013 Battery life:5 years Transmit power:RD environment test below-17db Features: Solar power charging; High and low pressure, leak alarm; LCD display screen, Simple user interface High accuracy, Using Freescale imported chips; Real-time monitoring tire pressure and temperature; Smart start: parking automatically sleep, the car starts automatically wake up. Two units(PSI / Bar) changeable, you can set the one you like. Sensors batteryChangeable Description: Solve the sensor does not work:Match sensor(Vent) Long press //menu key// 3 seconds to //U/S//,then short press //menu key// several times to enter//LID// interface,it shows ID of four tires and car icon. Short press //left/right select key// to learn ID opertion.Select tire you plan to learn ID of sensor by press//menu key//,default setting is //FL////FR////RR////RL. When tire is selected,display new //ID// in receiver after active sensor//s ID(internal sensor active by charging/vent tier). Do the same operation to match other three sensor.When all sensor are matched,short press //menu key// to save and go to //Ex//.