Theory Of Operation
WARNING: This page is about a different car, the 2016 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
The Body Control Module (BCM) provides a switched reference voltage on the fuel level signal circuit through a pull - up resistor that is connected to battery voltage. The BCM monitors the voltage on the fuel level signal 2 circuit. The fuel level signal is adjusted for changes in battery voltage. The voltage value is then transmitted as a network message on the communication network.