TPMS

TPMS (Tyre Pressure Monitoring System) is an essential active safety feature in modern vehicles. By monitoring tyre pressure and temperature in real time, it alerts the driver promptly to any abnormalities, such as slow punctures, over-inflation, severe under-inflation, or sudden blowouts. Maintaining correct tyre pressure is crucial not only for ensuring road safety and preventing serious accidents caused by blowouts, but also for reducing rolling resistance, improving fuel economy, and prolonging tyre life.

Core Technical Architecture and Operating Principle

TPMS systems are primarily categorised into direct and indirect systems, with direct TPMS being the mainstream standard today:

Wireless RF sensor transmission and direct pressure monitoring (Wireless RF Sensor Transmission and Direct Pressure Monitoring):

At the heart of direct TPMS is a high-precision wireless pressure and temperature sensor installed on each tyre valve or inside the rim. Powered by a built-in lithium battery, the sensor periodically samples absolute pressure and temperature data inside the tyre in real time, transmitting encrypted signals to the vehicle’s receiver antenna via high-frequency radio waves (typically 315 MHz or 433 MHz). 

Central controller calculation and instrument cluster visual warning (Central Controller Calculation and Instrument Cluster Visual Warning): 

The receiver module relays the captured wireless data to the Body Control Module (BCM) or a dedicated TPMS Electronic Control Unit (ECU). The system continuously evaluates real-time tyre pressure against preset safety thresholds; if pressure in any tyre drops below the safe limit (typically 25% below standard pressure) or if temperatures spike abnormally, a warning light immediately illuminates on the instrument cluster, pinpointing exactly which tyre is affected.

Safety Specifications and Operating Limitations

Never drive at high speeds or embark on long journeys if the TPMS warning light stays on, or if the system indicates severe pressure loss or sensor failure (Prohibiting High-Speed Travel When TPMS Low-Pressure Warnings Are Ignored):

Under-inflated tyres and excessive tyre temperatures are the primary causes of highway blowouts. Do not ignore tyre pressure warnings or simply clear the fault code without addressing the root cause. Safely pull over off the main road immediately, and inspect the tyres for punctures or slow leaks using a portable tyre inflator or by visiting a nearby service centre.

Never skip TPMS relearning and recalibration after tyre replacements, wheel rim upgrades, or tyre rotations (Prohibiting Omitting TPMS Relearning and Calibration After Tire Replacement or Rotation): 

When tyre positions are swapped without being reset via an OBD diagnostic tool or the on-board infotainment menu, the system will relay incorrect tyre position data. Driving without recalibration can be hazardous; for example, the cluster might flag an issue on the right tyre when the actual blowout is on the left, leading the driver to make wrong, critical decisions during an emergency manoeuvre.