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Tire Low Pressure Sensor
The tire pressure monitoring system uses ‘active’ tire low pressure sensors which are mounted on each wheel, inside the tire cavity. The sensor is retained in position by the valve attachment to the wheel. The tire low pressure sensors transmit their Radio Frequency (RF) signals at either 315 MHz or 433 MHz dependent on market requirements.
The tire low pressure sensor periodically measure the pressure and temperature of the air inside the tire. Pressure and temperature measurements are transmitted periodically to the external RF antenna on the vehicle.
The tire low pressure sensors are self-contained units which have no electrical connections into or out of the tire low pressure sensor.
The care points detailed in 'Tire Changing' must be followed to avoid damage to the tire low pressure sensor. If the tire low pressure sensor is removed, the nut, valve core, cap, seal and washer must also be replaced and the tire low pressure sensor tightened to the correct torque value. It is also recommended that the nut, valve core, cap, seal and washer are replaced at every tire change.
The RF transmission from the tire low pressure sensor contains a unique identification code in its transmission data, so that the tire pressure monitoring system module can identify the tire on the vehicle. If the tire low pressure sensor is replaced on a road wheel, the new sensor identification will be learnt when the vehicle is first driven at a speed of more than 20 km/h (12.5 miles/h) for 15 minutes. If a new tire low pressure sensor is fitted to the spare wheel, the identification for that tire low pressure sensor must be programmed into the tire pressure monitoring system module using a Jaguar approved diagnostic tool or that wheel will not be monitored. The code is provided on a label with the complete wheel and tire assembly when new and is also printed on the casing of each tire low pressure sensor.
In order to conserve battery power, the tire pressure monitoring system module uses different transmission rates when the wheel is stationary or moving. The wheel speed required to change between the stationary and moving transmission rates is approximately 20 kph (12.5 mile/h). |