a tire pressure monitor method enables the reassignment of tire pressure sensors to respective tire locations on the vehicle in the event that the sensors are lost or replaced with new sensors having differing identification codes . a passenger compartment monitors , that normally monitor tire pressures through broadcast transmission from the sensors , is manually put into an identification entry mode selecting a desired tire location , and when the vehicle begins travel , a motion switch in the new sensor detects vehicular motion and activates the transmission of the new identification code that is received by the monitor that then assigns the presently selected tire location to received identification code .