Low Fuel Indicator

When the ignition is in RUN or START, battery voltage is supplied from fuse 5 through the low fuel indicator light and parallel resistor to the thermistor in the fuel tank unit. The thermistor is grounded at G403. The thermistor has high resistance when cool and low resistance when warm. The current flowing through the thermistor heats it up. When the fuel level is above the thermistor, the fuel removes heat from the thermistor and the resistance remains high. The light does not go on. When the fuel level is below the thermistor, the fuel cannot keep the thermistor cool. As the thermistor warms up, its resistance is lowered and the indicator light comes on.