P0462

Schematic:

CIRCUIT DESCRIPTION

The fuel level sensor is device used to determine the level of fuel in the tank. The Powertrain Control Module (PCM) applies an ignition voltage to the sensor. The sensor varies the voltage based on the level of fuel in the tank. The sensor resistance is high when the tank is full, and the PCM senses a high signal voltage. As the fuel level in the tank decreases, the sensor resistance drops, and the signal voltage at the PCM is pulled low. The PCM uses the fuel level input in order to run certain system tests. Some of these system tests include the following:
^ EVAP system tests
^ Misfire tests
^ Oxygen sensor tests

The PCM also sends the fuel level information via Class 2 serial data to the Instrument Panel Cluster (IPC). The IPC uses the information to control the fuel gauge.

The PCM requires an accurate indication of fuel level for EVAP system diagnosis. The PCM monitors the fuel level sensor for signal voltages outside the normal range of the sensor. If the PCM detects a signal voltage less than the calibrated range of the sensor, DTC P0462 will set.

CONDITIONS FOR RUNNING THE DTC
^ The ignition is ON.
^ The system voltage is between 11 and 16 volts.

CONDITIONS FOR SETTING THE DTC
The PCM detects a fuel level sensor voltage that is less than 0.4 volts for at least 10 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store the conditions present when the DTC set as Fail Records data only.

Diagnostic Chart:

CONDITIONS FOR CLEARING THE MIL/DTC
^ The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
The DTC can be cleared by using the scan tool Clear DTC Information function.

DIAGNOSTIC AIDS

IMPORTANT: The fuel level is used to determine EVAP system diagnosis. Always diagnose the fuel level sensor before any other EVAP system components or DTCs.

Refer to A Diagnostic System Check - Instrument Cluster in Instrument Panel, Gauges and Console for additional diagnostic information. Testing and Inspection
^ Check for faulty connections at the PCM and/or the fuel level sensor-Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connections. Refer to Testing for Intermittent and Poor Connections in Diagrams.
^ Inspect the wiring harnesses for damage.

Reviewing the Failure Records vehicle mileage since the diagnostic test last failed may assist in diagnosing the condition. The information may help determine how often the condition that set the DTC occurs.