Fuel Pump Driver Module

WARNING: This page is about a different car, the 2019 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

The Fuel Pump Driver Module (FPDM) regulates the flow and pressure supplied by controlling the operation of the fuel pump using a Pulse Width Modulation (PWM) output. A PWM signal from the Powertrain Control Module (PCM) sends the FPDM the required speed for the fuel pump. The on time of the PWM signal represents half the pump speed. For example, if the PWM signal has an on time of 50%, the FPDM drives the pump at 100%.

The FPDM will only energize the fuel pump if it receives a valid PWM signal, with an on time of between 4% and 50%. To switch the fuel pump off, the PCM transmits a PWM signal with an on time of 75%.

The output pressure from the fuel pump will change with changes of engine demand and fuel temperature. The PCM monitors the input from the Low Pressure (LP) fuel pressure sensor and adjusts the speed of the fuel pump as necessary. The nominal output fuel pressure is 4.5 bar (65.3 psi), except during engine start-up. At engine start-up the target pressure for the fuel delivery line is 6.3 bar (91.4 psi).

If the PCM does not detect pressure in the fuel delivery line, it stops, or refuses to start the engine and stores the appropriate Diagnostic Trouble Code (DTC).

The PCM receives a monitoring signal from the FPDM. Any DTCs produced by the FPDM are stored by the PCM.

DTCs can be retrieved from the PCM using the Jaguar Land Rover approved diagnostic equipment. The FPDM itself cannot be interrogated by the Jaguar Land Rover approved diagnostic equipment.

The FPDM receives power supply via a fuel pump relay in the Rear Junction Box (RJB). The fuel pump relay is active in all power modes, except in power mode 0 (ignition off). The PCM is connected to the Body Control Module/Gateway Module (BCM/GWM) to receive a 'wake-up' message. In the event of an accident the Restraints Control Module (RCM) outputs an event signal to the BCM/GWM to disable the fuel pump relay.

If the RCM outputs an impact signal, the BCM/GWM de-energizes the fuel pump relay to prevent any further fuel being pumped to the engine.