DTC P1432: Fuel Pressure Sensor Signal Low: Description
WARNING: This page is about a different car, the 2002 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
Fuel Pressure Sensor (FPS) is a potentiometer. Alternate Fuel Engine Control Unit (AF ECM) supplies 5-volt reference voltage and ground circuit to FPS. When fuel level/tank pressure is full, FPS signal voltage increases to 4.1 volts. As fuel level/tank pressure decreases to empty, FPS signal voltage drops to about 0.5 volt. The AF ECM monitors FPS signal circuit voltage and Fuel Temperature Sensor (FTS) to determine amount of fuel in fuel tank.
This DTC is used to indicate an FTS signal voltage that is less than the normal operating range of the sensor.