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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Ensure the vehicle is parked on a level surface and secure with wheel chocks.
• Disconnect the negative battery terminal to prevent any electrical issues.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, and torque wrench.
• Remove the pre-catalytic oxygen sensor:
  • Locate the sensor near the exhaust manifold.
  • Use the O2 sensor socket to remove it by turning counterclockwise.
• Install the new oxygen sensor:
  • Apply anti-seize compound on the threads of the new sensor.
  • Hand-tighten it, then use the torque wrench to tighten to the manufacturer’s specifications (typically around 30 lb-ft).
• Repeat the process for the post-catalytic oxygen sensor if necessary.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if needed).
• Locate the catalytic converter and inspect for physical damage or clogs.
• If replacement is necessary:
  • Disconnect the exhaust pipes connected to the catalytic converter.
  • Use the exhaust pipe cutter to remove the old catalytic converter if it is welded in place.
  • Install the new catalytic converter, ensuring proper alignment.
  • Use a torque wrench to secure all bolts to the specified torque settings.

4. Clear Error Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the vehicle’s computer.
• Start the engine and allow it to reach operating temperature.