TPMS stands for Tire Pressure Monitoring System. It is a safety feature installed in modern vehicles to monitor the air pressure in the tires and alert the driver if there is a significant deviation from the recommended tire pressure. The primary purpose of TPMS is to enhance safety, improve fuel efficiency, and extend tire life.
There are two types of TPMS:
Direct TPMS:
Direct TPMS uses pressure sensors installed in each tire to monitor the tire pressure individually. These sensors transmit real-time tire pressure data to the vehicle’s onboard computer system. The sensors can detect both underinflation and overinflation of the tires. If the pressure in any tire falls below or rises above the recommended range, the TPMS system triggers a warning light on the dashboard to alert the driver.
Indirect TPMS:
Indirect TPMS uses the vehicle’s anti-lock braking system (ABS) sensors to indirectly monitor tire pressure. It relies on the rotational speed of each wheel to estimate tire pressure. When a tire’s pressure is significantly lower than the others, the wheel’s rolling diameter changes, resulting in a variation in wheel speed. The TPMS system detects this variation and triggers a warning light to notify the driver.
Here’s how TPMS works in practice:
Sensor Monitoring:
In direct TPMS, each tire has a pressure sensor mounted on the valve stem or inside the tire assembly. These sensors constantly measure the air pressure and transmit the information wirelessly to the TPMS control unit in the vehicle.
Data Processing:
The TPMS control unit receives the tire pressure data from the sensors and compares it to the recommended pressure values. It continuously monitors the pressure levels and can detect any significant deviations.
Warning System:
If the TPMS control unit detects that a tire’s pressure is too low or too high, it activates a warning light on the vehicle’s instrument panel. This light typically looks like a tire with an exclamation mark or a similar symbol. Some systems may also provide an audible warning or display the actual tire pressure values on the dashboard.
Maintenance and Resetting:
When adjusting the tire pressures or replacing tires, some TPMS systems require a reset procedure to relearn the new pressure values. This is typically done through a specific sequence of actions or using a TPMS tool.
TPMS helps drivers to stay informed about their tire pressures, allowing them to take corrective actions promptly. By maintaining the proper tire pressure, drivers can improve handling, braking performance, fuel efficiency, and tire longevity. It’s important to refer to your vehicle’s owner’s manual for specific instructions and information about your vehicle’s TPMS, as the features and procedures may vary between different car models.
