GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2007 🢒 TopKick C-Series (Conventional) C6/C7/C8 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0461

Circuit Description

The powertrain control module (PCM) monitors the signal circuit of the fuel level sender in order to determine fuel level. The sender consists of a variable resistor that changes resistance based on the fuel level in the tank. The PCM monitors the voltage across the sender resistance in order to determine the fuel level. The PCM uses the signal circuit of the fuel level sender in order to calculate the total remaining fuel, in percent. The PCM sends the fuel level percent via the serial data circuit to the instrument cluster in order to control the fuel gage. The fuel level information is also used for misfire and evaporative emission (EVAP) diagnostics.

This diagnostic tests for a stuck fuel level sensor signal for a single tank or for a stuck primary fuel level sensor signal for dual tanks. The PCM sets this DTC if the fuel level sensor signal appears to be stuck based on a lack of signal variation expected during normal operation.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0461 Fuel Level Sensor 1 Performance

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The PCM does not detect a change in the fuel level or a change in the primary fuel level of at least 3 L (0.79 gal) over a distance of 320 km (200 miles).

Action Taken When the DTC Sets
    • The fuel gage defaults to empty.
    • The PCM records the operating conditions at the time that the diagnostic test fails. The PCM displays 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/Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame/Failure Records data may help in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also help in determining the number of ignition cycles that the diagnostic test 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 at what point the DTC failed. Refer to Testing for Intermittent Conditions and Poor Connections .

Step

Action

Yes

No

Schematic Reference: Instrument Cluster Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

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 one of the following procedures:

    •  Fuel Sender Assembly Replacement for the 6.6L (LBZ and LLY) engine
    •  Fuel Sender Assembly Replacement for the 6.6L (LMM) engine
    •  Fuel Sender Assembly Replacement for the 7.8L engine
    •  Fuel Sender Assembly Replacement for the 8.1L engine

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