P0461

DTC P0461 Fuel Level Sensor Performance




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 malfunction.

Conditions for Setting the DTC
The fuel level has not changed more than 1.6% (4 counts) in 120 miles.

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 percent.

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 the following conditions:
- Poor electrical connection
- Rubbed through wire insulation
- A wire that is broken inside the wire 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 or damaged terminals
- Poor terminal to wire connection

Steps 1 - 3:

Steps 4 - 8:

Steps 9 - 13:

Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
1. The Powertrain OBD System Check prompts the technician to complete some basic checks and store the Freeze Frame data and the Failure Records on the scan tool if applicable. This creates an electronic copy of the data taken when the malfunction occurred. This information on the scan tool can be referred to later.
2. The fuel level display on the scan tool is displayed in percentage of fuel in the fuel tank It is also important to know approximately how much fuel is in the tank prior to performing this step.
9. Replacement PCMs must be programmed and the Crankshaft Position System Variation Learn Procedure must be performed. Refer to the latest Techline information for programming procedures.