a system for monitoring the condition of impulse lines to a differential pressure sensor . the lines may be connected at two locations of a pressure source , such as a pipe having a fluid flow . one line may direct a pressure of the source to one side of a piezoelectric diaphragm and another line may direct another pressure to the other side of the piezoelectric diaphragm . the diaphragm may provide an electrical indication of the differential pressure between both sides of the diaphragm . one of the lines may also be connected to a piezoelectric diaphragm of a static pressure sensor . the latter diaphragm may provide an electrical indication of static pressure . detection and comparison of noise levels of the electrical indications of the pressures may indicate if one or both lines are plugged , and which one if not both .