A TPMS sensor (Tire Pressure Monitoring System sensor) is a device installed in a vehicle’s tires to monitor air pressure and temperature. Here’s how it works:

1. Function: The TPMS sensor continuously measures the air pressure within each tire. If it detects a rapid deflation in one or more tires, it triggers the TPMS warning light on the dashboard.
2. Installation: The sensor is usually mounted on the inside of the tire. It sends information to a receiver that is either built into the car or connected to it. The receiver then displays the pressure readings for each tire on the car’s dashboard¹²³.
3. Indicator Light: The TPMS warning light typically appears as a yellow symbol resembling a tire cross-section (similar to a horseshoe) with an exclamation point. When this light illuminates, it indicates that at least one tire is significantly under-inflated, potentially creating unsafe driving conditions⁴.
4. Types of TPMS:
   • Indirect TPMS: This system relies on wheel speed sensors used by the anti-lock brake system. These sensors measure the rate of revolution of each wheel and compare them to each other and other vehicle operation data. When a wheel spins faster than expected, the computer calculates that the tire is underinflated and alerts the driver. Indirect TPMS doesn’t directly measure tire pressure but monitors tire rotation⁴.
   • Direct TPMS: This system uses individual pressure sensors mounted inside each tire. These sensors provide real-time pressure data for accurate monitoring. Direct TPMS is more precise but requires additional components and maintenance⁴.

Remember, maintaining proper tire pressure with the aid of TPMS helps prevent accidents and ensures safer driving experiences.