Fuel Level Sensor
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 Pontiac Grand Prix, 2003 Pontiac Bonneville, 2003 Chevrolet Monte Carlo, 2003 Chevrolet Impala, and 2003 Buick Regal. 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. See Fig 1. Fuel level sensor is part of the fuel sender assembly, located in the fuel tank. See Fig 2. 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 amount of fuel in the fuel tank. The Powertrain Control Module (PCM) sends the fuel level information via the Class 2 circuit to the Instrument Panel (IP) cluster. This information is used for the IP fuel gage and the low fuel warning indicator, if applicable. The PCM also monitors the fuel level input for various diagnostics.