Pacifica V6-3.8L (2008)
Tire Pressure Sensor: Description and Operation
Operation
OPERATION
The battery operated tire pressure sensors lay dormant (Park Mode), then wake and start transmitting (Drive Mode) when the vehicle first reaches speeds
over 15 mph (24 km/h). Once the wheels stop rotating for a period of approximately 20 minutes, the sensors shut down until again awaken. Although not
transmitting as when in Drive Mode, while in Park Mode, the sensors still transmit approximately once every 13 hours to let the receiver know air
pressure status at that time. Sensors will also transmit when a pressure change of one psi (seven kPa) or more is detected during that period.
Using an RF signal, each sensor transmits tire pressure data approximately once every minute. Each sensor's (transmitter) broadcast is uniquely coded so
that the Wireless Control Module (WCM), commonly referred to as the Sentry Key Remote Entry Module (SKREEM), can monitor the state of each of
the sensors in the four rotating road wheels. Once a sensor has been replaced and the vehicle has remained stationary for more than 19 minutes, the
WCM automatically learns and stores the sensor's ID while driving. This learning process can take up to 10 minutes while driving at speeds above 15
mph (24 km/h). There is no formal retraining procedure necessary.
