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

Solution

1. Preparation

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

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream oxygen sensor:
  • Locate the sensor on the exhaust manifold.
  • Use the O2 sensor socket to unscrew it.
  • Disconnect the electrical connector.
• Install the new upstream oxygen sensor:
  • Apply anti-seize compound to the threads (if required).
  • Thread it into place and tighten to manufacturer specifications (typically 30 Nm or 22 lb-ft).
• Repeat the process for the downstream oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, jack and jack stands, exhaust gasket, torque wrench
• Remove the catalytic converter:
  • Loosen the bolts connecting the catalytic converter to the exhaust manifold and the exhaust pipe using a socket set.
  • Support the converter and remove it from the exhaust system.
• Inspect the old catalytic converter for signs of clogging or damage.
• Install the new catalytic converter:
  • Position the new converter and align it with the exhaust manifold and pipe.
  • Use a new exhaust gasket to ensure a proper seal.
  • Tighten the bolts to the manufacturer's torque specifications (typically 40-50 Nm or 30-37 lb-ft).

4. Clearing the Error Code

• Reconnect the battery.
• Use the OBD-II scanner to erase the error codes from the vehicle's computer.

5. Final Check

• Start the engine and allow it to reach operating temperature.
• Monitor for any error codes and ensure the check engine light is off.