P0167 Fault Code

O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 3)

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0167 fault code refers to a malfunction in the O2 sensor heater circuit for Bank 2 Sensor 3. This sensor plays a crucial role in monitoring the exhaust gases and ensuring the optimal operation of the engine. Its heater element is designed to bring the sensor up to its operational temperature quickly, improving its accuracy and response time. When this circuit fails, it can lead to incorrect readings and potentially increase emissions.

What are the symptoms of the P0167 code?

Common symptoms associated with the P0167 fault code include:

• Check Engine Light illuminating on the dashboard.
• Poor fuel economy as the engine may run inefficiently due to inaccurate readings.
• Increased exhaust emissions, which can contribute to failing emissions tests.
• Rough idling or stalling in some cases, particularly if the engine is struggling to maintain optimal operation due to the faulty sensor.

What causes the P0167 code?

The O2 sensor heater circuit malfunction can be caused by several factors, including:

• A defective O2 sensor itself, which may have internal issues.
• Wiring problems, such as frayed or damaged wires.
• Poor electrical connections that may create intermittent or faulty signals.
• A blown fuse in the circuit that powers the sensor's heater.
• Issues with the engine control module (ECM) that processes the sensor's data.

How to fix P0167?

To rectify the P0167 fault code, the following steps can be taken:

• Begin with a thorough inspection of the O2 sensor and its wiring for any visible damage.
• Test the O2 sensor to determine if it is functioning correctly or needs replacement.
• Check and replace any blown fuses related to the O2 sensor heater circuit.
• Ensure that all electrical connections are secure and free from corrosion.
• If necessary, reprogram or replace the ECM if it is determined to be faulty.