Low Fuel Pressure Sensor
WARNING: This page is about a different car, the 2013 Infiniti M56. However, it is still accessible from the selected car via links, so may be relevant.
The low fuel pressure sensor is installed to low fuel pressure piping and measures the low fuel pressure. The sensor transmits voltage signal to the ECM. As the pressure increases, the voltage rises.
Courtesy of NISSAN NORTH AMERICA, INC.