P0461

Schematic:

The fuel tank level sensor is a variable resistor that varies resistance according to changes in the level of fuel in the fuel tank. The PCM supplies ignition voltage reference through a series of pull-up resistors to the sensor, which is connected to ground. When the level in the fuel tank is low, the sensor resistance is low (low voltage on signal line). As the fuel level increases, the sensor resistance increases (voltage increases on the signal line). The PCM uses the signal voltage to determine fuel tank level. The PCM sends the fuel tank level over the Class II link to the BCM. The BCM averages the signal over time then sends out a message to the I/P cluster for the fuel gauge over the link. DTC P0461 sets when the signal voltage at the PCM does not change a calibrated amount after the vehicle has been driven a long distance.

DTC PARAMETERS
DTC P0461 will set if fuel level changes less than 2% (0.09 volts) when:
^ Vehicle has been driven over 30 miles
^ DTC P0462 or P0463 has not been set

DTC P0461 diagnostic runs once per ignition cycle.

DTC P0461 is a type D DTC.

DIAGNOSTIC AIDS
This DTC sets due a fuel level that is not changing over driving time.

Use Scan tool to monitor FUEL LEVEL voltage while rocking vehicle back and forth. Voltage should change indicating a moving float.

Possible causes of static fuel level:
^ Fuel sender float stuck or perforated
^ Fuel sender sweep arm stuck