Disclosed is a tire pressure monitoring system for motor vehicles, including a central unit (2, 7) with at least one trigger module (4), which is integrated into the central unit or connects through control lines (3) to the central unit, and with at least one tire module (6) arranged in a vehicle wheel (5), with the tire module being in communication with the central unit and the trigger module by means of wireless transmission technology, and with the tire pressure monitoring system including fewer trigger modules than tire modules.