P0059 Fault Code

P0059 OBD-II Trouble Code Short Description

HO2S Heater Resistance (Bank 2, Sensor 1)

What does trouble code P0059 mean?

The P0059 fault code is related to the HO2S (Heated Oxygen Sensor) heater resistance in bank 2, sensor 1 of a car's engine.

Oxygen sensors are crucial for measuring the amount of oxygen in the exhaust gases. They help the engine control module (ECM) adjust the air-fuel mixture for optimal combustion and emission control.

The purpose of the heater in the oxygen sensor is to bring it up to operating temperature faster. This ensures accurate readings and efficient engine performance, especially during cold starts.

When the ECM detects a high resistance in the heater circuit of the oxygen sensor in bank 2, sensor 1, it generates the P0059 fault code. This could be due to a faulty oxygen sensor heater, damaged wiring or connectors, or a blown fuse.

To diagnose and fix this issue, you should start by inspecting the wiring and connectors for any signs of damage or corrosion. If any issues are found, they should be repaired or replaced. Checking the fuse related to the oxygen sensor heater is also recommended.

If the wiring, connectors, and fuse are in good condition, the oxygen sensor itself may be faulty and need replacement. It's essential to use a high-quality sensor compatible with your specific vehicle make and model.

After addressing the cause of the fault, the code should be cleared from the ECM using an OBD-II scanner. If the issue is resolved, the P0059 code should not reappear.

It's worth mentioning that a faulty oxygen sensor can negatively impact fuel efficiency, engine performance, and emissions. Therefore, it's important to address this issue promptly to ensure optimal vehicle operation.


What are the symptoms of the P0059 code?

P0059 is a fault code related to the HO2S (Heated Oxygen Sensor) heater resistance in bank 2, sensor 1. This code usually indicates a problem with the heating element in the oxygen sensor, which is responsible for measuring the oxygen levels in the exhaust gases.

Here are the symptoms commonly associated with a P0059 fault code on cars:

  • Check Engine Light (CEL) is illuminated: This is the most common symptom of a fault code. When the CEL is on, it means that the vehicle's onboard diagnostic system has detected a problem and has stored the corresponding fault code.

  • Decreased fuel efficiency: A faulty oxygen sensor can lead to an imbalanced air-to-fuel ratio, resulting in decreased fuel efficiency. If you notice a sudden drop in gas mileage, it could be related to a P0059 fault code.

  • Engine running rough: The incorrect air-to-fuel ratio caused by a faulty oxygen sensor can also lead to rough engine performance. You may experience engine misfires, hesitation, or a lack of power.

  • Failed emissions test: A malfunctioning oxygen sensor can cause the vehicle to fail an emissions test. This is because the sensor plays a crucial role in monitoring and regulating the emissions produced by the engine.

  • Poor engine performance: In severe cases, a faulty oxygen sensor can cause the engine to run poorly or even stall. This is because the sensor provides crucial feedback to the engine control unit (ECU), which adjusts various parameters for optimal performance.

If you are experiencing any of these symptoms, it is recommended to have your vehicle diagnosed and repaired by a qualified mechanic. They will be able to accurately determine the cause of the P0059 fault code and perform the necessary repairs or replacements.


What causes the P0059 code?

The P0059 fault code is triggered when there is a problem with the heater resistance of the HO2S (Heated Oxygen Sensor) in Bank 2 Sensor 1. This code indicates that there is an issue with the circuit or the performance of the heated oxygen sensor.

Possible causes for the P0059 fault code include:

  1. Faulty HO2S heater circuit: The problem could be due to a short or an open circuit in the heater circuit of the HO2S.
  2. Faulty HO2S heater element: The heating element within the oxygen sensor may be faulty or damaged.
  3. Poor electrical connection: A loose or corroded electrical connection at the sensor or an issue with the wiring harness could cause the fault code.
  4. Engine control module (ECM) failure: In some cases, the ECM itself could be responsible for the fault code.

It is recommended to have a qualified mechanic diagnose and repair the issue to avoid further damage to the vehicle. They will use a scan tool to retrieve the fault code and perform tests to determine the exact cause of the problem.

Possible Solutions

How to fix P0059?

To fix the P0059 fault code, which refers to the HO2S (Heated Oxygen Sensor) Heater Resistance for Bank 2, Sensor 1, you can follow these steps:

  1. Identify the location of Bank 2, Sensor 1: This sensor is typically located on the side of the engine with cylinder 2, in the exhaust manifold before the catalytic converter. Consult the vehicle's service manual or a professional mechanic for specific instructions.

  2. Inspect the wiring harness: Check for any visible damage or loose connections in the wiring harness connected to Bank 2, Sensor 1. Make sure all connections are secure and free from corrosion.

  3. Test the heater element: Use a multimeter to measure the resistance of the heater element of Bank 2, Sensor 1. The specific resistance value will depend on your vehicle's make and model. Compare the measured value with the manufacturer's specifications. If the resistance is outside the acceptable range, the sensor may need to be replaced.

  4. Replace the sensor: If the resistance of the heater element is out of range, replace Bank 2, Sensor 1 with a new one. Ensure you use a compatible sensor for your vehicle's make and model.

  5. Clear the fault code: After replacing the sensor, use an OBD-II scanner or code reader to clear the fault code from the engine control unit (ECU). This will reset the system and allow you to monitor if the code reoccurs.

  6. Test the system: Take your vehicle for a test drive to see if the fault code reappears. Monitor the sensor readings using an OBD-II scanner to ensure the new sensor is functioning properly.

If you are unable to troubleshoot or fix the issue on your own, it is recommended to consult a qualified mechanic or take your vehicle to a professional repair shop for further diagnosis and repair.