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Fuel Level Sensor: Description and Operation

DESCRIPTION
The fuel level sensor (fuel gauge sending unit) consists of a float, a float arm and a variable resistor. The fuel level is measured by the position of the float in the fuel tank, and is indicated by a gauge in the Instrument Panel (I/P) cluster assembly. When the fuel level changes, the float position changes. The change in the float position increases or decreases the resistance reading of the variable resistor. The change in the resistance causes the position of the fuel gauge needle to change.