P0462

Diagnostic Chart:

Schematic:

CIRCUIT DESCRIPTION
The fuel level sensor is device used to determine the level of fuel in the tank. The PCM applies an ignition voltage to the sensor. The sensor varies the voltage based on the level of fuel in 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 run certain system tests. Some of these system tests include the following:
^ The EVAP system
^ Misfire
^ The oxygen sensor

The PCM also sends the fuel level information via class 2 serial data to the 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 below the calibrated range of the sensor, DTC P0462 will set.

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

CONDITIONS FOR SETTING THE DTC
The PCM detects a fuel level sensor voltage that is less than 0.4 volt 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 conditions which were present when the DTC set as Failure Records data only. This information will not be stored as Freeze Frame data.

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

DIAGNOSTIC AIDS

IMPORTANT: 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.
^ Check for poor 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 poor terminal to wire connection. Refer to Testing for Intermittent and Poor Connections.
^ Damage harness.
Inspect the wiring harness(es) for damage.

Reviewing the Fail 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.