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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure safety by wearing gloves and safety glasses.
• Disconnect the battery to prevent any electrical issues.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the pre-catalytic and post-catalytic oxygen sensors on the exhaust manifold and downstream of the catalytic converter respectively.
  2. Disconnect the electrical connectors from both oxygen sensors.
  3. Use a socket wrench to remove the sensors from their mounting locations.
  4. Install new oxygen sensors, ensuring they are torqued to the manufacturer's specifications (typically around 30 ft-lbs).
  5. Reconnect the electrical connectors.

3. Examine and Replace Catalytic Converter

• Sub-steps:
  1. Inspect the catalytic converter for any signs of damage, such as dents or rust.
  2. If damaged, remove the catalytic converter by unbolting it from the exhaust system using a socket set.
  3. Install a new catalytic converter, ensuring proper alignment with the exhaust system.
  4. Torque the mounting bolts to manufacturer specifications (usually around 30 ft-lbs).
  5. Reconnect any exhaust hangers and ensure everything is secure.

4. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the vehicle's battery.
  2. Use an OBD-II scanner to clear the P0420 code from the ECU.
  3. Start the engine and let it idle for a few minutes.
  4. Conduct a test drive to ensure the check engine light does not reappear.