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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure electrical safety.
• Raise the vehicle securely on jack stands if access to the underside is needed.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, penetrating oil.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Apply penetrating oil to the sensor threads if they are rusted.
  3. Use the O2 sensor socket to carefully remove the sensors.
  4. Install new oxygen sensors, ensuring they are torqued to the manufacturer's specifications (usually around 30 lb-ft).

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if needed).
• Sub-steps:
  1. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  2. Remove any mounting bolts or brackets securing the catalytic converter.
  3. Inspect the old catalytic converter for signs of damage or blockage.
  4. Install the new catalytic converter, securing it with bolts and ensuring a proper seal.
  5. Torque the bolts to manufacturer specifications (typically around 25 lb-ft).

4. Clear Codes and Test

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the engine and allow it to reach normal operating temperature.