Fuel Level Sensors

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.

Two fuel level sensors are used to measure the amount of fuel remaining in the left and right sides of the fuel tank. The left passive fuel level sensor 'B' is attached to the tank internal bracket and the right active fuel level sensor 'A' is attached to the outside of the fuel pump swirl pot. Both sensors are connected to the vehicle wiring harness via the external electrical connector on the fuel pump module top flange assembly.

The electrical output signal varies to the amount of fuel remaining in each side of the fuel tank and the position of the float arms. The measured resistance is measured by the fuel level sensors and the information passed to the Body Control Module/Gateway Module (BCM/GWM) which implements an anti-slosh function. This monitors the signal and updates the fuel level signal to the instrument cluster at regular intervals, preventing constant pointer movement caused by fuel movement in the tank due to cornering or braking. A low level fuel warning indicator is incorporated in the instrument cluster which illuminates when the fuel level in the tank falls below a predetermined level.

The fuel level sensor signals are converted into Controller Area Network (CAN) bus messages by the BCM/GWM and are used by the instrument cluster for fuel gauge and fuel warning indicator operation and are also monitored by the Engine Control Module (ECM) to store On-Board Diagnostics (OBD) P codes for mis-fire detection when the fuel level is below a predetermined capacity.