Fuel Rail Pressure Sensor
The fuel rail pressure sensor is a dual analog sensor that provides two fuel rail pressure signals to the engine control module (ECM) and is located in the end of the fuel rail assembly. The ECM provides a 5 V reference voltage on the 5 V reference circuit and ground on the low reference circuit. The ECM receives a varying signal voltage on both the fuel rail pressure sensor and fuel rail pressure sensor 2 signal circuits. The ECM monitors the voltage on both of the fuel rail pressure sensor circuits and compares the values to determine if the sensors are accurate. When the fuel pressure is high, the fuel rail pressure sensor signal voltage is high and the fuel rail pressure sensor 2 signal voltage is low. When the fuel pressure is low, the fuel rail pressure sensor signal voltage is low and the fuel rail pressure sensor 2 signal voltage is high.