P0462

Diagnostic Chart:

Schematic:

The fuel 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 high, the sensor resistance is high (low voltage on signal line). As the fuel level decreases, the sensor resistance decreases (voltage increases on the signal line). The PCM uses the signal voltage to determine fuel tank level. The PCM sends the fuel level over the Class II link to the BCM. The BCM averages the signal over time then sends a message to the I/P cluster over the link to position the gauge. DTC P0462 sets when the fuel level sensor signal voltage at the PCM is below the calibrated voltage value.

DTC PARAMETERS
DTC P0462 will set if fuel level voltage is less than 0.2 volts when:
^ Condition exists for longer than 1 second
^ Ignition voltage is greater than 9 volts

DTC P0462 diagnostic runs continuously with ignition On.

DTC P0462 is a type D DTC.

DIAGNOSTIC AIDS
To locate an intermittent problem, use Scan tool to monitor FUEL LEVEL SENSOR voltage with ignition On, engine Off. Wiggling wires while watching for a change in FUEL LEVEL SENSOR voltage may locate the area where a short to ground in the wiring could lie.

The voltage measured with a DVOM on the signal line with the ignition On and sensor disconnected should read very close to ignition voltage (within 0.2 volts). The Scan tool, however, is scaled 0 to 5 volts.

Check for corrosion in the harness connectors. Corrosion will cause a short to the return circuit and may set this DTC.

If DTC P0462 is active, the fuel gauge will read EMPTY and the Low Fuel telltale will be commanded On.