DeVille DHS V8-4.6L VIN Y (2000)
Fuel Level Sensor: Description and Operation
The fuel level sensor is a rheostat mounted on the fuel sender assembly. The PCM supplies the sensor with a 5 volt reference and a ground. The sensor
varies the 5 volt input voltage based on the level of fuel in the tank. The PCM uses the signal voltage to calculate the amount of fuel in the tank.
The fuel level sensor is part of the fuel sender assembly. The PCM uses the fuel level input to make sure that the level of fuel in the tank is sufficient to
run the EVAP tests. The PCM also sends the fuel level information via Class 2 to the Instrument Panel Cluster (IPC). The IPC uses the information to
control the fuel level gauge.
The PCM performs the key ON and RUN tests to determine the status of the L-terminal circuit. During the key ON test, if the PCM detects a high signal
voltage, DTC P0621 will set. DTC P0621 will also set if, during the RUN test, the PCM detects a low signal voltage. The PCM also sends a Class 2
serial data message to illuminate the charging telltale.
