I just purchased a new vehicle, and it has an automated tire pressure sensor in each valve stem or wheel.
From this site
The system is designed to work with the receivers used for remote keyless entry. Antennas are installed in each wheel well. The keyless remote entry receiver, which uses rolling ID numbers to match keys to cars, is modified so that it can send out a low-frequency signal through the wheel well antennas.
The low-frequency signal “wakes up” an active (that is, battery-powered) RFID tag either in the tire valve or inside the rim of the tire. The active tag then broadcasts ? at either 315 MHz or 434 MHz – its rolling ID number, which identifies the tire and its location and data on the temperature and pressure of that tire.
I’ll be…… I don’t know. Damned? Saved? Incredible.
Don’t get me wrong, I really love the new car (Pathfinder). But sometimes I feel like I need permission from mission control to go anywhere. I guess, in a way, I do.
Our 2000 Corvette has the same feature. It’s worked perfectly for 6 years now. We periodicly double check and the sensor has been right on.