Low Fuel Warning Light Sensor: Legacy

Remove fuel tank sending unit. At fuel tank sending unit connector, connect 12-volt battery positive lead to Green/Blue wire terminal and negative lead to Black wire terminal. Connect 12-volt, 3-watt light bulb in series with positive lead.
With sending unit float submerged in gasoline, light bulb should be off. With sending unit float not submerged, light bulb should be on. If light does not respond as specified, replace sending unit.