P0461

Fuel Level Sensor Circuit Performance:

Fuel Level Sensor Circuit Performance (continued):

Fuel Level Sensor Circuit Performance:

Circuit Description

The Powertrain Control Module (PCM) uses the fuel level input from the fuel level sensor to calculate expected vapor pressures within the fuel system. Vapor pressures vary as the fuel level changes. Vapor pressure is critical to determining if the Evaporative Emissions (EVAP) System is operating properly. Fuel level is also used 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

^ Fuel level change check: maximum to minimum is less than 2 gallons.

^ Condition present once per drive cycle.

Action Taken When the DTC Sets

^ The Malfunction Indicator Lamp (MIL) will illuminate after two consecutive ignition cycles in which the diagnostic runs with the fault active.

^ The PCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Freeze Frame buffer.


Conditions for Clearing the MIL/DTC

^ The MIL will turn "OFF" after three consecutively passing cycles without a fault present.

^ A History DTC will clear after 40 consecutive warm-up cycles without a fault.

^ DTC(s) can be cleared by using a scan tool or by disconnecting the PCM battery feed.


Diagnostic Aids

Check The Following Conditions:

^ If DTC P0463 is also displayed, go to DTC P0463 first.

^ Poor connection at PCM. Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire connection.

^ Damaged harness. Inspect the wiring harness for damage.

^ A stuck fuel level sensor may cause DTC to set.

If DTC P0461 cannot be duplicated, the information included in the Freeze Frame data can be useful in determining vehicle operating conditions when the DTC was first set.

If any wiring repairs need to be made, Refer to Repair Procedures in Diagrams.

Resistance checks for the fuel level sensor: At Empty = 100 ohms or over, At Half full = about 32.5 ohms, At Full 10 ohms or less.


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 data on the scan tool if applicable. This creates an electronic copy of the data taken when the fault occurred. The information is then stored in the scan tool for later reference.

2. Determine if fault is present. Reviews Freeze Frame data to determine when the DTC set. Always record this information.

7. If the fuel level gage (in I/P cluster assembly) is stuck at empty it may be caused by a short to ground in the fuel level sensor signal wire.