P0463

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 fuel level in the fuel tank changes the rate of vacuum decay for the EVAP system leak DTCs.

The PCM monitors the fuel level sensor for signal voltages outside the normal range of the sensor. If the PCM detects a signal voltage above the calibrated range of the sensor, DTC P0463 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 more than 3 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 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.

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.