P0461

Circuit Description
The Engine Control Module (ECM) uses the signal from the fuel level sensor to calculate expected vapor pressure within the fuel system. Vapor pressure varies as the fuel level changes. Vapor pressure is critical in determining if the Evaporative Emission (EVAP) system is operating properly. The fuel level signal is also used to determine if the fuel level is too high or too low to be able to accurately detect EVAP system faults. This Diagnostic Trouble Code (DTC) indicates a stuck fuel level sensor.

Conditions for Setting the DTC
- The change in the raw fuel level sensor output is less than 5 counts (0.1 volt) within 250 km (155 miles).
- Ignition ON.

Action Taken When the DTC Sets
- The Malfunction Indicator Lamp (MIL) will not illuminate.
- A history DTC is stored.

Conditions for Clearing the MIL/DTC
- A history DTC will clear after 40 consecutive warm-up cycles without a fault.
- The DTC(s) can be cleared by using the scan tool.

Diagnostic Aids
An intermittent may be caused by a poor connection, rubbed-through wire insulation or a wire broken inside the insulation.

Check for a poor connection or damaged ECM harness. Inspect the fuel level circuit terminals for the following conditions:
- Improper mating
- Broken locks
- Improperly formed
- Damaged terminals
- Poor terminal-to-wire connection
- Damaged harness

Steps 1 - 7:

Steps 8 - 11:

Test Description
The number(s) below refer to step(s) on the diagnostic table.
1. The On-Board Diagnostic (OBD II) 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 on the scan tool for later reference.
2. If either DTC(s) P0462 or P0463 are also displayed, refer to the relevant DTC tables first.
6. Resistance checks for the fuel level sensor:
- Empty = 280 ohms or more.
- Half full = about 90 ohms.
- Full = 38 ohms or less.

9. The replacement ECM must be reprogrammed. Refer to the latest Techline procedure for the ECM reprogramming.