Fuel Level Sensing

The Body Function Controller (BFC) calculates fuel level and sends a serial data message to the Instrument Cluster indicating fuel level. The fuel level is calculated as a ratiometric reading between the Fuel Level Sensor and an Ignition 1 reference voltage. By using this method, changes in system voltage will have no effect on fuel level. The Body Function Controller (BFC) sends changes in fuel level information to the Instrument Cluster over the Serial Peripheral Interface (SPI) serial data bus.