Fuel Pump Driver Module (FPDM)

Courtesy of JAGUAR CARS, INC.

The fuel pump driver module (FPDM) is located under the rear right-hand (RH) seat and is attached to the underside of a cover plate. The fuel pump control module receives a power supply via the fuel pump relay in the auxiliary fuse box.

The engine control module (ECM) sends a pulse width modulation (PWM) signal to the fuel pump driver module (FPDM) from pin 20 of connector C0635 of the engine control module (ECM), the duty cycle of the signal determines the duty cycle of the pump. The engine control module (ECM) sets a target fuel pressure based on engine load. The target fuel pressure is maintained by using feedback from the fuel rail pressure sensor which is used to control the fuel pump via a closed loop pulse width modulation (PWM) signal. The pulse width modulation (PWM) signal to the pump represents half the ON time of the pump. If the engine control module (ECM) transmits a 50% on time the fuel pump control module drives the pump at 100%. If the engine control module (ECM) transmits a 5% ON time the fuel pump control module drives the pump at 10%. The fuel pump control module will only turn the fuel pump ON if it receives a valid signal between 4% and 50%. When the engine control module (ECM) requires the fuel pump to be turned OFF the engine control module (ECM) transmits a duty cycle signal of 75%.

The status of the fuel pump driver module (FPDM) is monitored by the engine control module (ECM) on connector C0635 pin 21. Any errors can be retrieved from the engine control module (ECM). The fuel pump control module cannot be interrogated for diagnostic purposes.

The engine control module (ECM) controls the fuel pump driver module (FPDM) in response to inputs from the fuel rail pressure sensor, manifold absolute pressure (MAP) and the mass air flow (MAF)/intake air temperature (IAT) sensor.