Component description Charge-air pressure sensor (51.27421–0181) Ground – Supply + 4 1 Output 3 2 Plug connection Function The pressure sensor element consists of an Si-diaphragm which contains several piezo-resistive (pressure- sensitive) semiconductor resistors. The pressure to be measured “deflects” the sprung diaphragms. As a result, extended or compressed zones are created on the surface of the diaphragms. The action of these forces changes the electrical ratings of semiconductor resistor arrays arranged in these zones. These va- lues are a measure for the pressure to be measured. Curve (VDC) 4,500 4.650 MIN Overpres- sure 0.350 MIN 0,500 Vacuum 0,5 4,0 VS Pressure (bar) 16