This fuel level sensor monitors the fuel quantity in the tank and sends a corresponding electrical signal to the gauge or control unit. It is mounted in the fuel system of the host tractor, where the float arm moves with the fuel surface to vary the resistance in the sender circuit. A failed sensor causes an inaccurate or erratic fuel gauge reading, which can lead to unexpected fuel starvation in the field. The sensor is built to the original dimensional and electrical specifications so it matches the tank mounting flange and the gauge calibration curve without adjustment.