P2252 Code: O2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 1

The oxygen sensor checks how much oxygen there is in the exhaust gases produced by the engine burning a mixture of air and fuel. It converts the oxygen content into a voltage signal and sends it to the engine control module (ECM) or powertrain control module (PCM). The controller uses the readings to adjust various engine and fuel system processes, thereby achieving the most fuel-efficient operation.

If the control circuit powering oxygen sensor #1 on engine bank 1 showed a negative current, the PCM will log a P2252 code.

What Does the P2252 Code Mean?

The diagnostic trouble code (DTC) P2252 indicates “O2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 1.” Bank 1 indicates the side of the engine with cylinder 1. Oxygen sensor 1 refers to the upstream device located in front of the catalytic converter.

Modern vehicles have multiple O2 sensors. Preheated by battery voltage to get them into operational condition, the sensors measure the oxygen content in the exhaust gases as the latter enter and exit the catalytic converter.

The oxygen sensors send voltage signals corresponding to the amount of oxygen detected. Higher voltage outputs indicate less oxygen, which indicates the exhaust gases are rich. Conversely, lower voltage outputs indicate the exhaust is lean.

The PCM regularly checks the oxygen sensors. If the voltage reading from the O2 sensor #1 is much lower and doesn’t match the right parameters, it will set the generic code P2252. It can take more than one ignition cycle before the controller activates the check engine light or malfunction indicator lamp.

Note: The definition of code P2252 can differ according to the vehicle manufacturer. Check the appropriate repair manual or repair database for the exact code definition.

What are the Common Causes of a Code P2252?

What are the Common Symptoms of a Code P2252?

How to Diagnose the P2252 Code

The P2252 code is a generic code that can be logged by different makes and models. Despite its prevalence, the process to determine its exact issue and the steps to fix it can vary between vehicles. What works in one instance may not apply to a different case.

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.

How to Fix the P2252 Code

You will need the correct tools and appropriate knowledge to effectively repair the problem with the oxygen sensor that caused the P2252 code. In most cases, it’s best to leave the job to professionals.

DIYers with advanced technical knowledge and hands-on experience can personally test and replace their vehicle’s O2 sensors. To make the job easier, they can refer to the right repair manual or consult an online repair database.