P2066 Code: P2066 Fuel Level Sensor “B” Performance

The fuel level sensor gauges how much gasoline or diesel remains in your vehicle’s fuel tank. It sends its readings to the powertrain control module (PCM). The module delivers the information to the fuel gauge on the instrument panel and other controllers through the data communication bus.

The PCM will log a P2066 code if it receives a voltage signal from the fuel level sensor that does not match any of the signals programmed into the module.

What Does the P2066 Code Mean?

Diagnostic trouble code (DTC) P2066 indicates “Fuel Level Sensor ‘B’ Performance.”

Most fuel level sensors are fitted on the top of either the fuel tank or the fuel pump. Depending on your vehicle’s make and model, the sensor can be found in a different location.

When the fuel level changes, the electrical resistance of the fuel level sensor changes as well. The sensor converts its resistance into a voltage signal and sends it to the PCM.

The PCM checks the fuel level sensor’s voltage signal during the start-up sequence. It also monitors the sensor’s signal circuit. If the module gets a response that doesn’t match any of the correct operating voltages stored in its memory, it will set the generic engine/powertrain code P2066.

Note: The definition of code P2066 can differ depending on the vehicle manufacturer. Check the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of the P2066 Code?

• Faulty fuel level sensor
• Bad PCM
• Fuel level sensor or PCM wiring problem

What are the Common Symptoms of the P2066 Code?

• Check engine light turns on
• Reduced distance to empty mileage
• Inaccurate fuel level depicted by a fuel gauge

How to Diagnose the P2066 Code

The P2066 code is a generic powertrain code and engine code that various makes and models can log. However, this does not mean that there is a one-size-fits-all solution to determine what’s causing the problem.

If you’re not confident about conducting diagnostic tests on your vehicle, it’s a good idea to bring it to a professional mechanic. Otherwise, you can go ahead and diagnose the issue yourself. Here is a video that can give you an idea of what the process might involve:

How to Fix the P2066 Code

Attempting to fix a P2066 code can become a challenging task. In most cases, it’s best to leave the job to professionals.

But if you have the right tools and know-how to test and replace the fuel level sensor, you can resolve the problem on your own. It will be helpful to rely on a repair manual or refer to an online repair database. Make sure it contains repair processes that are specific to your vehicle’s year, make, and model.