Fuel Level Sensor: Description and Operation

FUEL LEVEL SENSOR-PCM INPUT
The fuel level sensor (fuel gauge sending unit) sends a variable voltage to the Powertrain Control Module (PCM) to indicate fuel level. The purpose of this feature is to prevent a false setting of misfire and fuel system monitor trouble codes if the fuel level is less than 15 percent of its rated capacity.

CIRCUIT OPERATION
The fuel level sensor is a variable resistor. Circuit K226 provides the fuel level signal to cavity C26 of the Powertrain Control Module (PCM). The PCM provides ground for the fuel level sensor signal on circuit K167. Circuit K167 connects to cavity A4 of the PCM. The PCM broadcasts fuel level data on the CCD bus. The microprocessor in the instrument cluster monitors the CCD bus to determine the fuel level and adjusts fuel gauge needle position accordingly.