Tire pressure sensor
WARNING: This page is about a different car, the 2006 Honda Odyssey and 2005 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
Each sensor is an integrated unit made up of the tire valve stem, a pressure sensor, and a transmitter. The unit is attached to the inside of the wheel, around the valve stem. The sensor transmits a signal to the control unit when tire pressure is less than 168 kPa (1.7 kgf/cm2 , 24 psi). The control unit then turns on the low pressure indicator and the appropriate tire(s) indicator. When that tire's pressure is increased to more than 198 kPa (2.0 kgf/cm2 , 29 psi), the transmitter stops sending the signal, and the control unit turns the indicators off.