Tire pressure sensor
WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. 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 the internal tire information to the control unit once every 60 seconds. When the TPMS control unit receives a the pressure reading of less than 175 kPa (1.8 kgf/cm2 , 25 psi), the control unit then turns on the low tire pressure indicator and the appropriate tire(s) indicator. When that tire's pressure is increased to more than 200 kPa (2.0 kgf/cm2 , 29 psi), the transmitter sends the tire pressure reading to the control unit, and then the control unit turns the indicators off.