Fuel Level Sensor
WARNING: This page is about a different car, the 2003 Pontiac Sunfire, 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, and 2003 Chevrolet Cavalier. 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 Powertrain Control Module (PCM) sends the fuel level information via the Class 2 circuit to the Instrument Panel Cluster (IPC). This information is used for the IPC fuel gauge and the low fuel warning indicator, if applicable. The PCM also monitors the fuel level input for various diagnostics.