P0463

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION

The PCM uses the fuel level input in order to calculate the expected vapor pressures within the fuel system. These vapor pressures vary as the fuel level changes. The vapor pressure is critical in determining if the Evaporative Emissions System is operating properly. The PCM also uses the fuel level in order to determine if the fuel level is too high or too low to be able to accurately detect EVAP system faults.

CONDITIONS FOR SETTING THE DTC

The Fuel Level Sensor should be greater than 98% for greater than 25 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM records the operating conditions at the time the diagnostic fails. The Failure Records buffers will store this information.

^ A history DTC is stored.

^ The fuel tank level defaults to 40%.

CONDITIONS FOR CLEARING THE DTC

^ A history DTC clears after 40 consecutive warm up cycles without a fault.

^ The scan tool can clear the DTC.

DIAGNOSTIC AIDS

^ An intermittent problem may be caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation.

^ Any circuitry, that is suspected as causing the intermittent complaint, should be thoroughly checked for the following conditions:

- Backed out terminals.

- Improper mating.

- Broken locks.

- Improperly formed.

- Damaged terminals.

- Poor terminal to wire connection.

^ Install an additional ground wire from the Instrument Panel Cluster (IPC) to the negative side of the battery if electrical interference is suspected.

Refer to Diagrams for additional diagnostic information.

TEST DESCRIPTION

Number(s) below refer to the step number(s) on the Diagnostic Table.

1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the freeze frame and failure records data on the scan tool if applicable. This creates an electronic copy of the data taken when the malfunction occurred. The information is then stored in the scan tool for later reference.

3. This step simulates a DTC P0462. If the PCM senses the change, then the PCM and the Engine Coolant Temperature (ECT) wiring are OK.

10. Replacement PCMs must be reprogrammed and the crankshaft position system variation procedure must be performed. Refer to the latest Techline information for PCM reprogramming and also refer to the Crankshaft Position (CKP) System Variation Learn Procedure for the Crankshaft Position System Variation Procedure.