P0461 - Fuel Level Sensor 1 Performance

Fig 1: Identifying Fuel Level Sensor Circuit

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

For a complete wiring diagram, refer to appropriate Wiring Diagram.

Theory of Operation

The Fuel Level Sensor information is a bussed message to the Powertrain Control Module (PCM) from the Totally Integrated Power Module (TIPM). The fuel level rationality will set a fault for a fuel level reading that does not change over an accumulated mileage threshold to keep stuck high or stuck low fuel levels from disabling OBD monitors. The power up test looks to see a large enough fuel level voltage change from the last key-off to the following engine run. The engine run test looks to see a fuel level voltage change over an accumulated mileage.

>>When Monitored:<< TEST No. 1: With the ignition on, the fuel level is compared to the previous key down after a 20 second delay. TEST No. 2: The PCM monitors the fuel level at ignition on.
>>Set Condition:<< TEST No. 1: If the PCM does not see a difference in fuel level of greater than 0.1 volt the test will fail. TEST No. 2: If the PCM does not see a change in the fuel level over a set amount of miles the test will fail. Two trip fault. Three good trips to turn off the MIL.

Possible Causes
CAN BUS FAILURE
FUEL LEVEL SENSOR CIRCUIT DTCS SET IN THE TIPM
FUEL TANK
OBSTRUCTION TO THE FUEL LEVEL SENSOR
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .

Test Step 1 - ACTIVE DTC

NOTE:

Diagnose and repair any Can bus, communication or implausible signal DTCs before proceeding with this test.

NOTE:

Diagnose P0462 or P0463 first, if set along with P0461.

Start the engine.
Allow the engine to reach normal operating temperature.
With the scan tool, select View DTCs.

NOTE:

It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.

Is the DTC Active or Pending at this time?

Yes

Go to Test Step 2

Perform the Checking for an Intermittent DTC diagnostic procedure. Refer to CHECKING FOR AN INTERMITTENT DTC Engine .

Test Step 2 - VISUALLY INSPECT FUEL TANK

Visually inspect the Fuel Tank for damage that may restrict the Fuel Sending Unit float from moving.

Is the Fuel Tank OK?

Yes

Go to Test Step 3

Replace the Fuel Tank as necessary.
Perform the Powertrain Verification Test. Refer to PCM VERIFICATION TEST (2009 - 2011) or PCM VERIFICATION TEST (2012 & UP) .

Test Step 3 - FUEL LEVEL SENSOR CIRCUIT DTCS SET IN THE TIPM

Are any Fuel Level Sensor Circuit DTCs set in the TIPM?

Yes

Diagnose the appropriate Fuel Level Sensor Circuit DTC in the TIPM. Refer to DIAGNOSIS AND TESTING .

Go to Test Step 4

Test Step 4 - INTERNAL INSPECTION OF THE FUEL TANK

WARNING:

The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.

Remove the Fuel Tank in accordance with the Service Information.
Remove the Fuel Pump Module. Refer to REMOVAL AND INSTALLATION .
Visually inspect the inside of the Fuel Tank for any obstructions or deformities.
Inspect the Fuel Pump Module Float arm for damage.

Were any problems found?

Yes

Repair or replace as necessary.
Perform the Powertrain Verification Test. Refer to PCM VERIFICATION TEST (2009 - 2011) or PCM VERIFICATION TEST (2012 & UP) .

Go to Test Step 5

Test Step 5 - POWERTRAIN CONTROL MODULE (PCM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Totally Integrated Power Module (TIPM) and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched or partially broken wires.
Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Sensor and Powertrain Control Module connectors.
Perform any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

Repair as necessary.
Perform the Powertrain Verification Test. Refer to PCM VERIFICATION TEST (2009 - 2011) or PCM VERIFICATION TEST (2012 & UP) .

Replace and program the Powertrain Control Module. Refer to REMOVAL AND INSTALLATION .
Perform the Powertrain Verification Test. Refer to PCM VERIFICATION TEST (2009 - 2011) or PCM VERIFICATION TEST (2012 & UP) .