Fuel Level Sensor
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. 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 cord. The position of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which changes resistance in correspondence to the amount of fuel in the fuel tank. The engine control module (ECM) sends the fuel level information via the class 2 circuit to the instrument panel (I/P) cluster. This information is used for the I/P fuel gauge and the low fuel warning indicator, if applicable. The ECM also monitors the fuel level input for various diagnostics.