how to fix P0420 code on Honda CR-V Sixth Generation (2023-present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety.
• Allow the vehicle to cool down completely before working on the exhaust system.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Tools Required: O2 sensor socket, torque wrench, penetrating oil (if needed).
• Sub-steps:
  1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
  2. Use penetrating oil on the base of the sensors to facilitate removal.
  3. Disconnect the electrical connectors from both oxygen sensors.
  4. Remove the sensors using the O2 sensor socket.
  5. Install the new sensors by threading them into place and tightening to manufacturer's specifications (typically around 30 lb-ft).
  6. Reconnect the electrical connectors.

3. Replace the Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, exhaust clamps (if required).
• Sub-steps:
  1. Lift the vehicle using a jack and secure it with jack stands.
  2. Locate the catalytic converter in the exhaust system.
  3. Remove any heat shields if applicable.
  4. Unbolt the catalytic converter from the exhaust pipes, using a socket set.
  5. Inspect the gaskets and replace if damaged.
  6. Install the new catalytic converter, ensuring it fits properly.
  7. Bolt it back in place and reattach any heat shields.

4. Clear Error Codes

• Use the OBD-II scanner to clear the P0420 code from the ECU.
• Reconnect the negative battery terminal.