GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Vivant 🢒 Engine 🢒 Engine Controls - 2.0L (L34 GMDAT) 🢒 DTC 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. The fuel level signal also used to determine if the fuel level is too high or too low to be able to detect evaporative emission (EVAP) system faults. This DTC indicates the fuel level is stuck.

Conditions for Setting the DTC
    • The change in the fuel level sensor output is less than 3.5 percent.
    • The ignition is ON.
    • DTC P0462, P0463, and P0502 are not set.

Action Taken When the DTC Sets
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The ECM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffers.
    • 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.
    • DTCs can be cleared by using the scan tool.
    • Disconnect the ECM battery feed for more than 10 seconds.

Diagnostic Aids

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

Inspect for a poor connection or damaged ECM harness. Inspect the fuel level circuit terminal for the following conditions:

    • Improper mating
    • Broken locks
    • Improperly formed
    • Damaged terminals
    • Poor terminal-to-wire connection
    • Damaged harness

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. The Diagnostic System Check - Engine Controls 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.

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

Step

Action

Values

Yes

No

1

Perform the Diagnostic System Check - Engine Controls.

Was the check performed?

--

Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

  1. Install a scan tool to the data link connector (DLC).
  2. Start the engine and operate the vehicle over the specified mileage.

Are any of the DTCs P0462, P0463, or P0502 set?

250 km (155 mi)

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the fuel pump connector.
  3. Turn ON the ignition.
  4. Using a voltmeter, measure the fuel level signal voltage at the fuel level sensor connector terminal 1.

Is the voltage within the specified value?

4-5 V

Go to Step 4

Go to Step 5

4
  1. Disconnect the engine control module (ECM).
  2. Inspect the fuel level sensor ground circuit for an open between terminal 6 of the fuel sensor connector and terminal K34 of the ECM and repair as needed.

Is the repair complete?

--

Go to Step 10

Go to Step 6

5

Using a voltmeter, measure the voltage at the ECM connector terminal K34 by back-probing the ECM connector.

Is the voltage within the specified value?

4-5 V

Go to Step 8

Go to Step 9

6
  1. Remove the fuel pump from the fuel tank.
  2. Reconnect the fuel pump connector.
  3. Turn ON the ignition.
  4. Monitor the fuel level sensor parameter on the scan tool while moving the fuel sensor float from empty to full position.
  5. Repeat procedure 4 several times.

Does the fuel level sensor value on the scan tool increase and then decrease steadily when the float is moved?

--

Go to Diagnostic Aids

Go to Step 7

7
  1. Turn OFF the ignition.
  2. Replace the fuel pump assembly. Refer to Fuel Pump Replacement .

Is the repair complete?

--

Go to Step 10

--

8
  1. Turn OFF the ignition.
  2. Disconnect the ECM connector.
  3. Inspect the fuel level signal circuit for an open or short to ground between terminal K51 and the fuel pump harness connector terminal 1 and repair as needed.

Is the repair complete?

--

Go to Step 10

--

9
  1. Turn OFF the ignition.
  2. Replace the ECM. Refer to Engine Control Module Replacement .

Is the repair complete?

--

Go to Step 10

--

10
  1. Using the scan tool, clear the DTCs.
  2. Start the engine and idle at normal operating temperature.
  3. Operate the vehicle within the Conditions for Setting the DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic ran and passed?

--

Go to Step 11

Go to Step 2

11

Are any DTCs displayed that have not been diagnosed?

--

Go to Diagnostic Trouble Code (DTC) List

System OK