GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2002 🢒 Express 🢒 Engine 🢒 Engine Controls - 8.1L 🢒 DTC P0461

Circuit Description

The fuel level sensor changes resistance based on the fuel level. The PCM monitors the signal circuit of the fuel level sensor in order to determine the fuel level. When the fuel tank is full, the fuel level sensor resistance is high and the PCM senses a high fuel level sensor signal voltage. When the fuel tank is empty, the fuel level sensor resistance is low and the PCM senses a low fuel level sensor signal voltage. The PCM uses the signal circuit of the fuel level sensor in order to calculate the total remaining fuel percentage in the tank. The PCM sends the fuel level percentage via the fuel level signal circuit to the instrument cluster in order to control the fuel gage. The fuel level information is also used for misfire and EVAP diagnostics.

This diagnostic tests for a stuck fuel level sensor. The PCM sets this DTC when the fuel level sensor signal appears to be stuck based on a lack of signal variation expected during normal operation.

Conditions for Running the DTC
    • The ignition is ON.
    • The PCM detects that the fuel tank is between 15 percent and 85 percent full.

Conditions for Setting the DTC

The PCM does not detect a change in fuel level of at least 3.0 L (0.79 gal) over a distance of 320 km (200 mi).

Action Taken When the DTC Sets
    • The fuel gage defaults to empty.
    • The PCM records the operating conditions at the time the diagnostic fails. The PCM stores 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 PCM receives the clear code command from the scan tool.

Diagnostic Aids

Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may help to determine the number of miles since the DTC set. The Fail Counter and Pass Counter can also help determine the number of ignition cycles that the diagnostic 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 when the DTC failed.

Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Step

Action

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2
  1. Remove the fuel level sender.
  2. Inspect for the following items:
    3. • The fuel level sensor is stuck, perhaps due to an interference with the fuel strainer.
    • The fuel tank contains foreign material, for instance ice.

Did you find and correct the condition?

Go to Step 4

Go to Step 3

3

Replace the fuel level sensor. Refer to the appropriate application.

    •  Fuel Level Sensor Replacement in Engine Controls - 4.3L
    •  Fuel Level Sensor Replacement in Engine Controls - 5.0L and 5.7L
    •  Fuel Level Sensor Replacement in Engine Controls - 8.1L

Did you complete the replacement?

Go to Step 4

--

4
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC reset?

Go to Step 2

System OK