P0463

DTC P0463 (2.8L and 3.6L)

Circuit Description

The primary fuel level sender and the secondary fuel level sender change resistance in response to fuel level. The engine control module (ECM) monitors the signal circuit of the primary fuel level sender and the secondary fuel level sender in order to determine the fuel level. When the fuel tanks are full, the resistances of both fuel level senders are high, and the ECM senses a high signal voltage on both the signal circuit of the primary fuel level sender and the signal circuit of the secondary fuel level sender. When the fuel tanks are empty, the resistances of the fuel level senders are low, and the ECM senses a low signal voltage. The ECM uses the signal circuits of the primary fuel level sender and the secondary fuel level sender in order to calculate the percentage of remaining fuel in the tanks. The ECM sends the fuel level percentage via the class 2 serial data circuit to the instrument cluster in order to control the fuel gage. The fuel level information is also used for misfire and evaporative emission (EVAP) diagnostics. This diagnostic tests for a higher than normal primary fuel level sender signal.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0463 Fuel Level Sensor Circuit High Voltage

Conditions for Running the DTC

* The engine is running.
* The system voltage is between 10-18 volts.
* Fuel level state is stable.

Conditions for Setting the DTC

* The primary fuel level signal is about 3.2 volts.
* The primary fuel level sensor signal is about 64 percent.
* The above condition is present for about 60 seconds.

Action Taken When the DTC Sets

* The fuel gage defaults to empty.
* The driver information center (DIC) displays the FUEL LEVEL LOW message.
* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.
* The history DTC clears after 40 malfunction-free warm-up cycles.
* The ECM receives the clear code command from the scan tool.

Diagnostic Aids

Use the Freeze Frame/Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame/Failure Records data may help in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also help in determining the number of ignition cycles that the diagnostic test reported a pass and/or fail. Operate the vehicle within the same Freeze Frame conditions, including those for RPM, for engine load, for vehicle speed, for temperature, and for others. This will isolate at what point the DTC failed.

Refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Test Description

Step 1 - Step 11:

Step 12:

The number below refers to the step number on the diagnostic table.
3. This step tests for the proper operation of the circuit in the low voltage range.