Error Code P0460: Fuel Level Sensor Circuit Malfunction
Table of Contents
Error Code P0460 is defined as Fuel Level Sensor Circuit Malfunction. Meaning, there’s a discrepancy detected between the fuel gauge and the actual fuel level of the tank, which could be caused by a problem in the fuel sensor.
This code is a generic trouble code, meaning it applies to all vehicles equipped with OBD-II, especially those 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) detects a discrepancy between fuel gauge input and the actual fuel level in the tank, then the Error Code P0460 will be registered.
Related Error Codes include:
- P0461 Fuel Level Sensor Circuit Range/Performance
- 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.
Symptoms for this error code depend on the severity of the problem. If the problem is caused by a mechanical failure, then it’s usually a severe case. If it’s caused by an electrical problem, then it’s considered not severe, as the PCM can compensate for it. Compensation simply means the fuel gauge reads Empty or Full at the time.
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
Vehicles that come with a low fuel blinker feature may also suffer from erratic low fuel warnings in the event of a P0460.
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 most error codes, diagnosing this code starts with the use of an OBD-II code reader.
Next, they check the electrical circuitry and look for signs of damage, disconnected wires, and corrosion. If the electrical circuits look good, they will proceed with checking the components for damages or faults.
If the sensor is in good shape as well, then they will proceed on checking the fuel tank and the PCM and look for signs of damage.
If the vehicle’s computer has logged any other trouble codes, you may use them to guide your search for the problem.
How to Fix
Common repairs for this code include:
- Repair or replacement of corroded, broken, or disconnected wiring in the electrical circuitry of the fuel sensor
- Cleaning of the fuel tank ground and connections with the PCM
- Testing of the voltage throughout different segments of the system between tank, sensor, and the PCM. If there’s a discrepancy in the voltage of more than 1V between segments, then there’s a good chance it’s the cause of the problem. In which case, replacement or reconnection of the faulty component is required.
- After conducting the repairs, the vehicle must be started, and all fuel related systems must be checked to ensure the repairs have been completed.
Error Code P0460 isn’t usually a serious problem that causes vehicle malfunction or drivability problems unless it comes in tandem with other trouble codes. Having an inaccurate reading of your fuel level, of course, can be risky, as you’re uncertain of how much fuel the vehicle has. Thus, if you need to make a short trip with this code present, then you have to check the fuel levels manually.