Theory of Operation
WARNING: This page is about a different car, the 2011 Jeep Patriot and 2011 Jeep Compass. However, it is still accessible from the selected car via links, so may be relevant.
The Tire Pressure Trigger Module is used to automatically learn the location of each wheel sensor on the vehicle. The module is controlled and activated in sequence by the Wireless Control Module (TPM) over a LIN bus. When activated, the module will generate a 125 KHz signal of sufficient field strength to trigger the tire pressure sensor and force a RF transmission from the sensor.