Low Pressure Fuel Circuit
The low pressure fuel circuit pumps fuel of pressure approximately 450 - 670 kPa (4.5 - 6.7 bar, 4.59 - 6.834 kg/cm 2 , 65.25 - 97.15 psi) to the high pressure fuel pump from the fuel tank through the fuel filter under any conditions. The fuel pump control module (FPCM) controls fuel pump according to the following sensors and signals.
- Fuel pressure sensor (Fuel pressure in the low pressure fuel circuit)
- ECM (Target fuel pressure)
The fuel pump is activated when the fuel pump control module (FPCM) receives a fuel pump ON signal from ECM. FPCM evaluates current fuel pressure according to a voltage signal from the fuel pressure sensor and sends the information to ECM via drivetrain CAN communication. ECM calculates a target fuel pressure based on fuel pressure and load requirement and transmits a target fuel pressure signal to FPCM via drivetrain CAN communication. FPCM controls the fuel pump so that the target fuel pressure can be satisfied. The fuel pressure is limited to a maximum of 700 kPa (7 bar, 7.14 kg/cm 2 , 101.5 psi) by the fuel pressure regulator.