Which statement about tire pressure sensors is true?

The correct statement is that the sensors can be part of the valve stem assembly. Tire pressure monitoring systems (TPMS) often integrate the sensors directly into the valve stem unit for a more compact and effective design. This integration allows the sensor to monitor tire pressure directly and transmit that information to the vehicle's onboard diagnostics system.

Many modern vehicles utilize these integrated sensors because they simplify installation and maintenance while also reducing the overall number of components required for tire pressure monitoring. Therefore, when servicing or replacing tires, it is common for technicians to check the condition of these sensors, as replacing them may be necessary if there's any sign of damage or if they are malfunctioning.

In contrast to this, while some battery life in certain sensors can be long-lasting, it's not universally guaranteed for a minimum of 15 years, and batteries in these sensors are typically not designed to be easily replaceable. Additionally, while it's a good practice to check the sensor condition when tires are replaced, it is not a requirement to replace them each time unless necessary.