Fuel Level Sensor
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2018 GMC Yukon XL, 2018 GMC Yukon, 2018 Chevrolet Tahoe, 2018 Chevrolet Suburban, and 2018 Cadillac Escalade ESV. However, it is still accessible from the selected car via links, so may be relevant.
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor card. The position of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor which changes resistance in correspondence with the position of the float arm. The engine control module (ECM) sends the fuel level information via high speed CAN - bus to the body control module (BCM). The BCM then sends the fuel level percentage via low speed CAN - bus to the instrument panel cluster (IPC) in order to control the fuel gauge. The control module monitors the signal circuit of the fuel level sensor in order to determine the fuel level.