how to fix the P0135 oxygen sensor code on Honda Civic 9th Generation (2012-2015)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Ensure the engine is cool before starting work.

2. Remove the Faulty Oxygen Sensor

• Locate the upstream O2 sensor (usually found before the catalytic converter).
• Disconnect the wiring harness from the O2 sensor.
• Use an oxygen sensor socket or wrench to unscrew the sensor from the exhaust manifold.
• Carefully remove the sensor and set it aside.

3. Install the New Oxygen Sensor

• Apply anti-seize compound to the threads of the new O2 sensor (if not pre-applied).
• Install the new oxygen sensor into the exhaust manifold and tighten it to the manufacturer's torque specification (typically around 30-40 lb-ft).
• Reconnect the wiring harness to the new sensor.

4. Check Circuit Integrity

• Reconnect the negative battery terminal.
• Use a multimeter to check the voltage at the O2 sensor connector with the ignition on (engine off) to ensure it receives power.
• Check the ground wire continuity to the O2 sensor to ensure proper grounding.

5. Clear the Codes and Test Drive

• Use an OBD-II scanner to clear the P0135 code from the ECU.
• Start the engine and allow it to warm up to check for proper operation of the new O2 sensor.
• Take the vehicle for a test drive to ensure the check engine light does not reappear.