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

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the vehicle's battery to ensure safety.
• Raise the vehicle using jack stands for accessibility.

2. Inspect and Replace Oxygen Sensors

• Tools Needed: O2 sensor socket, wrench
• Sub-steps:
  1. Locate the pre-catalytic converter and post-catalytic converter oxygen sensors.
  2. Disconnect the electrical connector for each oxygen sensor.
  3. Use an O2 sensor socket to remove the sensors from their respective locations.
  4. Install new oxygen sensors (ensure they match OEM specifications).
  5. Reconnect the electrical connectors securely.

3. Inspect and Replace Catalytic Converter

• Tools Needed: Socket set, torque wrench, exhaust gasket
• Sub-steps:
  1. Remove any components obstructing access to the catalytic converter (e.g., heat shields).
  2. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  3. Remove the catalytic converter by unbolting it from the exhaust manifold and the rear pipe.
  4. Compare the old catalytic converter with the new one to ensure proper fit.
  5. Install the new catalytic converter with a new gasket, tightening bolts to manufacturer specifications (typically around 25-30 lb-ft).
  6. Reinstall any removed components in reverse order.

4. Clear Codes and Test Drive

• Tools Needed: OBD-II scanner
• Sub-steps:
  1. Reconnect the vehicle's battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the engine and allow it to reach normal operating temperature.
  4. Perform a test drive to ensure the vehicle runs smoothly and check for reoccurrence of the check engine light.