TPMS is a system fitted to a vehicle which constantly monitors the pressures or pressure imbalance in the tyres and provides a warning to the driver if these fall below a certain threshold. However, TPMS should not be seen as a replacement for regular manual tyre safety checks. Two types of TPMS systems are fitted on cars today:
- Direct systems use radio sensors mounted inside of each wheel to measure the tyre inflation pressures – they ‘directly’ measure the pressure within each tyre and send the data to a control unit
- Indirect systems utilise the vehicle’s existing ABS sensors to measure and compare the rotational speeds of the tyres and vibrations to ‘indirectly’ calculate the pressure within the tyres.