Error Code P0461 is defined as Fuel Level Sensor Circuit Range/Performance.

This code is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II, especially made from 1996 up to the present day. It is, however, more common among Chrysler, GM, Ford, Lincoln, Mercury, Kia, Mazda, Mercedes Benz, Infiniti, Nissan and Subaru vehicles. Specifications on the definition, troubleshooting, and repairs, of course, vary from one make and model to another.

Definition

The fuel level sensor (also known as sender) is an essential component of the fuel pump module and located in the fuel tank. This component can’t be replaced without replacing the pump module, though there are some exceptions. Attached to the arm is a float that travels with a resistor grounded to the tank, frame or a dedicated ground circuit. The sender receives a supplied voltage, and the ground path changes according to the level of fuel. The amount of voltage depends on the system, but in many times it’s around 5V.

As the fuel level changes, the float moves the arm, changing the resistance to ground which varies the voltage signal. This signal will either go straight to the fuel pump computer module, or to the instrument cluster module. Depending on the vehicle’s system, the fuel pump computer module may only monitor the resistance to ground, and then relay the fuel level information to the instrument panel. If the PCM (powertrain control module, also known as ECM or engine control module in other vehicle makes) determines that the voltage input signal at the fuel level sensor is incorrect, and doesn’t match with the actual amount of fuel in the gas tank of the vehicle, then the Error Code P0461 will be set.

Other related Error Codes include:

  • P0460 Fuel Level Sensor Circuit Malfunction
  • P0462 Fuel Level Sensor Circuit Low Input
  • P0463 Fuel Level Sensor Circuit High Input
  • P0464 Fuel Level Sensor Circuit Intermittent

Common Symptoms

As with other error codes, this code activates the Check Engine light as its first symptom.

Common symptoms include:

  • Incorrect fuel level on gauge in instrument cluster – always reads wrong
  • Erratic fuel gauge
  • Decrease in perceived fuel economy
  • Decrease in distance to Empty mileage

Possible Causes

Common causes for this code include:

  • Open in the signal circuit to the FLS sensor
  • Short to voltage in the signal circuit to the FLS sensor
  • Short to ground in the signal circuit to the FLS sensor
  • Failed FLS Sensor/sensing arm stuck mechanically
  • Failed PCM (rare)

How to Check

As with other Error Codes, diagnosing this code requires the use of an OBD-II scanner connected to the vehicle’s communication port. This is usually found on the driver side, under the dash. The codes will be read and get cleared. The vehicle will be test driven to verify the code’s return.

Next, the mechanic will disconnect the fuel sending unit connector and ground wire before checking the whether the fuel gauge moves to either full or empty with the key on. The gauge DOES move, then it’s not the cause of the problem, and the mechanic can move to diagnosing the rest of the system.

If the gauge DOES NOT move, then the problem is in the cluster, which must be replaced. The mechanic must remove the cluster and check the circuit, and look for signs of corrosion or damages to the wiring for the clusters.

If the gauge moved as described, then the mechanic will look for damages to the wiring harness and connectors of fuel sending sensor.

The mechanic also checks the fuel tank grounding strap’s condition and remove any corrosion that might have formed, as this can also cause the P0461 code.

How to Fix

The most common fix for this code is replacing the fuel gauge or the instrument cluster. However, other repairs may be necessary, such as:

  • Repair or replacement of damaged wiring harness
  • Replacement of damaged fuel tank grounding wire or strap
  • Replacement of damaged fuel tank
  • Replacement of defective PCM (on rare condition)
  • Replacement of fuel level controller (on rare conditions)

Though Error Code P0461 doesn’t result to drivability problems, it’s important to have this problem diagnosed and repaired as soon as possible. Having an inaccurate fuel reading means you have no idea how much fuel there is in your tank. And unless you top off every day, there’s a possibility you will run out of gas while on the road, leaving you stranded.