P0463 OBD-II error code: high fuel level sensor circuit input.
Diagnostic Trouble Code (DTC): P0463
P0463 Code Definition.
When the Powertrain Control Module (PCM) receives an input signal from the fuel gauge (or fuel level sensor) greater than the actual fuel level in the tank, it registers code P0463 and the Check Engine light comes on.
What P0463 means
The PCM determines the amount of fuel in the tank using low voltage input signals. Typically, the highest voltage reading will be five volts, and any voltage reading outside the normal range set by the manufacturer will result in a P0463 code.
What causes the P0463 code?
Some of the most common reasons for a PCM to store a P0463 code are:
- Problem with the fuel level sensor circuit.
- Defective fuel level sensor
- Defective fuel level sensor floats in the fuel tank.
- Damage or corrosion of the fuel tank.
- PCM problem (rare)
What are the symptoms of code P0463?
There are several symptoms that a driver can detect when a P0463 code is registered. These include:
- The check engine light comes on.
- Fluctuating or inaccurate fuel gauge
- The fuel indicator light comes on and/or the low fuel alarm sounds.
How can a mechanic diagnose the P0463 code?
When diagnosing the P0463 code, the mechanic will first check this code and any other codes that have been recorded with the OBD-II scanner. They will then erase the code and attempt to reconstruct the circumstances under which it was first recorded. While doing so, they will monitor the fuel gauge and the data it provides, determining whether it is erratic or steady, whether it indicates that there is more or less fuel in the tank than there actually is, and so on.
Once this test is done, the mechanic will systematically work through the probable causes, erasing the code and retesting with each repair until the code is finally resolved.
The most common errors when diagnosing the P0463 code
Technicians report some of the most common diagnostic errors and mistakes with the P0463 code:
- Replace the fuel pump when the problem is actually a damaged or defective fuel gauge or fuel level sensor.
- Replace larger, more expensive components before checking wires and connectors for faults or short circuits.
- Replace the fuel gauge if the problem is a corroded or damaged wire or connector.
How serious is the code P0463?
This code is not an immediate threat to your vehicle, but it can put you in a dangerous or at least uncomfortable situation. If you don’t know how much fuel your vehicle has, you could run out of fuel when you are away from home or in bad conditions. If your vehicle is stuck in traffic due to lack of fuel, the situation can also be very dangerous.
What repairs can fix a P0463 code?
Some of the most common repairs for the P0463 code include:
- Fuel tank repair or replacement
- Repair or replacement of fuel level sensor float
- Repair or replace the fuel level sensor float.
- Replace the wiring harness of the fuel level sensor.
- Tighten the loose connection in the fuel level sensor circuit.
Additional notes on code P0463
While you may be able to determine how much fuel your vehicle has based on mileage, it is still important to resolve this code as soon as possible, especially if you need to obtain an OBD-II emissions test to renew your vehicle’s registration in your state. When the fuel level sensor is read as inaccurate or erratic, the PCM will keep the Check Engine light on, which means you cannot pass the emissions test until the problem is resolved. Fortunately, however, this problem can usually be easily repaired without incurring a large cost.
