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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery before beginning work.

2. Inspect and Replace Oxygen Sensors

• Inspect the upstream and downstream oxygen sensors:
  • Disconnect the electrical connectors from both sensors.
  • Remove the sensors using an O2 sensor socket.
  • Inspect for damage or contamination.
• Replace any faulty sensors:
  • Install new sensors and connect the electrical connectors.

3. Inspect and Replace Catalytic Converter

• Remove the catalytic converter:
  • Loosen and remove the bolts or clamps securing the catalytic converter to the exhaust pipes.
  • Carefully detach the converter from the mounting points.
• Install the new catalytic converter:
  • Position the new catalytic converter in place and secure it using the original bolts or clamps, ensuring the correct torque specifications (typically around 30-50 lb-ft, but refer to the specific service manual).
  • Make sure all gaskets are in good condition and replace them if necessary to prevent leaks.

4. Reconnect Battery and Clear Codes

• Reconnect the battery terminals securely.
• Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.