This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
P0462 is an OBD-II Code that refers to Fuel level Sensor Circuit Low Input
A P0462 code is caused by an ECM (Engine Control Module) receiving a signal from the PCM that Fuel Sensor reading is too low to be correct and is not within the acceptable range. When this occurs, the ECM will set and store this code.
Common causes for this code include:
- Faulty Fuel Level Sensor
- Short to Ground or Open in Fuel Level Sensor Circuit
- The tank for fuel has been damaged in some manner, such as being punctured or crushed.
- Fuel Level Sensor electrical connectors have been disconnected, damaged or corroded
- Open or Ground Short for Fuel Pump circuit
- Faulty ECM
- Bad PCM readings from faulty sensors
The symptoms of a P0462 code are:
- MIL (Malfunction Indicator Lamp) Illumination
- The fuel will not work properly
- Perhaps Reduced Engine Power / Reduced MPG
To diagnose a P0462 DTC code, a technician would:
- Look for the fault code stored in the ECM history Freeze Frame data
- Check for damaged wiring and connectors to the fuel level sensor, as well as conditions that may have caused the damage
- Check for a deteriorated or contaminated fuel supply
- Test the PCM and all related systems, to ensure that they are working properly.
The following are some of the most common mistakes that a technician may make when diagnosing a P0462 code:
- Failing to check the freeze frame data
- Not checking for proper electrical signals at mating connectors or wiring harnesses
- Assuming that a vacuum leak is causing performance issues, when in fact it may be a fault with the fuel level sensor
- Replacing parts without first confirming that they are faulty
- Not confirming that all related systems are working properly
How serious is this?
A P0462 code isn't an immediate catastrophic problem, however it is something to be aware of, and take care of as soon as possible. If left uncorrected, it could eventually lead to other problems such as reduced fuel economy (MPG) and/or efficiency; or perhaps even a no start condition.
What repairs can fix the code?
The following are solutions that may fix this problem:
- Replacing a faulty fuel level sensor
- Re-calibrating the PCM as a possible fix for a bad reading from a faulty ECM
- Replacing or repairing a damaged fuel tank, wiring or connectors that may have been affected in some way
- Inspecting and confirming proper operation of all related systems, such as the fuel pump, to ensure they are working properly
- Replacing a faulty ECM as the most likely solution if all other options have been tried and no fault code is found. (Rare)
A P0462 is related to and may be accompanied by the following codes:
P0480 – Cooling Fan 1 Control Circuit Malfunction
In conclusion, the P0462 code is a generic trouble code that means the computer has detected an issue with the Fuel level Sensor and its input. Without the input it receives from this device, the vehicle's ECM is unable to determine how much fuel there is in the tank; not knowing how much fuel can be potentially harmful for performance and drivability. Common causes include a faulty Fuel Level Sensor or high resistance in its circuit due to wiring damage or corrosion. By checking freeze frame data, voltage levels at mating connectors and conducting tests on related systems.