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

Solution

1. Preparation

• Gather tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shocks.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Use an O2 sensor socket to remove the upstream oxygen sensor.
  3. Install the new upstream oxygen sensor and torque it to the manufacturer's specification (typically around 30 Nm).
  4. Repeat the process for the downstream oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Remove the exhaust heat shield if applicable to access the catalytic converter.
  2. Unbolt the catalytic converter from the exhaust manifold and exhaust pipe using a socket set.
  3. Inspect the flanges for cracks or damage; replace the catalytic converter if necessary.
  4. Install the new catalytic converter, ensuring proper alignment and sealing.
  5. Torque the bolts to manufacturer specifications (usually around 30-40 Nm).
  6. Reattach the exhaust heat shield if removed.

4. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the battery terminals.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the vehicle and let it idle for a few minutes.