A tyre pressure monitoring system or TPMS is an electronic system for monitoring the air pressure in a vehicle tyre and automatically transmitting a warning to the driver in the event of an under and, in some cases, over inflated tyre. These systems have been legislated to be progressively installed on all new passenger carrying US and EU vehicles and similar legislation is being introduced worldwide.

The majority of systems use direct tyre sensors which transmit real time tyre pressure information to the driver of the vehicle either via a dashboard display or a warning light referred to as the tread light. The sensors are physical pressure transducers which are attached to the back of the valve stem or are in a form which is banded to the wheel.

The Tyre Pressure Monitoring System sensors also transmit data such as their unique sensor ID, temperature, pressure, battery life (where applicable) and other diagnostic information. This data is sent to the Engine Control Unit (ECU) or specific receiver on the vehicle. Those vehicles which have graphical displays of the sensor positions can then show on which wheel there is a problem.

Transceiver pairing