how to fix Honda CR-V Fifth Generation (2017-2022) P0420 code

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, jack and jack stands, safety glasses, gloves.
• Disconnect the battery to prevent electrical shock.
• Raise the vehicle securely using a jack and jack stands.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  • Locate Bank 1 Sensor 1 (pre-catalytic converter) and Bank 1 Sensor 2 (post-catalytic converter).
  • Unplug the electrical connectors from both oxygen sensors.
  • Use a socket wrench to remove each sensor.
  • Install the new oxygen sensors by reversing the removal process, ensuring they are tightened to the manufacturer's specifications (typically 30 ft-lbs).
  • Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Sub-steps:
  • Remove the exhaust heat shield if applicable.
  • Unbolt the catalytic converter from the exhaust manifold and the exhaust pipe using a socket set. Note the orientation of the catalytic converter for correct reinstallation.
  • Inspect the mating surfaces for damage or corrosion; clean as necessary.
  • Install the new catalytic converter, ensuring proper alignment and torque specifications (generally around 30 ft-lbs).
  • Reinstall the exhaust heat shield and any other components removed during the process.

4. Reconnect Battery

• Reconnect the negative terminal of the battery securely.

5. Clear Codes and Test Drive

• Use the OBD-II scanner to clear the P0420 code from the vehicle's memory.
• Test drive the vehicle for at least 20 minutes to allow the ECU to monitor the operation of the catalytic converter and oxygen sensors.