Fuel Level Sensor: Description and Operation

Fig.29 Fuel Gauge Pressure Sensor Location:

The fuel gauge pressure sensor (transducer) is mounted to a fuel control valve. This valve is located at the rear end of the left outer (side mounted) fuel cylinder.

A three-wire (three-circuit), temperature compensated sensor (transducer) monitors fuel pressure in the high-pressure side of the fuel system. One of the wires supplies a 12 volt power source to the sensor. Another wire supplies a ground for the sensor. The third wire supplies a voltage signal from the sensor back to the Powertrain Control Module (PCM).

The sensor is used to vary its input voltage depending on fuel cylinder pressure. As fuel cylinder pressure increases, voltage decreases. As pressure decreases voltage increases. The voltage signal is returned back to the PCM through the sensor return circuit. The PCM will then interpret this resistance (voltage) data and send a message across the multiplex bus circuits to the instrument panel cluster. Here it is translated into the appropriate fuel gauge level reading. Refer to Instrument Panel for additional information. Output voltages from the sensor will vary from about 0.6 volts at FULL, to about 7.0 volts at EMPTY.


NOTE: For diagnostic purposes, this voltage can only be verified with the fuel gauge pressure sensor circuit closed (i.e. having all of the sensor circuits electrical connectors connected).

Fuel gauge calibration is the same as for gasoline powered models. For more information, refer to Instrument Panel and Gauges.

The electrical circuits between the fuel gauge pressure sensor and the PCM are hard-wired (not multiplexed).