NANO

ENGINE 14 8. PRESSURE AND TEMPERATURE (P&T) SENSOR Function: P & T Sensor is used to sense the pressure and temperature of the gas in the gas rail coming from the LP filter. Working Principle: Pressure Sensor: A DC signal volt is produced by this sensor when varying CNG pressure acts on the semiconductor diaphragm. To produce this output the semiconductor device has to be excited. This signal output varies with change in the CNG rail pressure. Temperature Sensor: Semiconductor material changes it’s resistance when exposed to variable temperature source (i.e. gas temperature). Type:  Pressure sensor: Piezoelectric.  Temperature sensor: NTC. Location of Component: This sensor is fitted on gas rail. System Integration: This sensor provides gas rail pressure & temperature input to CNG ECU. The sensor is activated by excitation voltage supplied by CNG ECU. Wiring details (CNG ECU & Sensor): 1: ECU pin 208 : PIN1 2: ECU pin 137 : PIN4 3: ECU pin 226 : PIN3 4: ECU pin 225 : PIN2