how do I fix the P0420 code on my Honda Pilot Third Generation (2016-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to prevent any electrical issues during repair.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, multimeter.
• Sub-steps:
  1. Remove the O2 sensor from the exhaust pipe using the O2 sensor socket.
  2. Inspect the sensor for damage or contamination.
  3. If faulty, install a new O2 sensor by reversing the removal steps.
  4. Reconnect the battery and clear the fault codes.

3. Check and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack, jack stands, exhaust pipe cutter (if needed).
• Sub-steps:
  1. Raise the vehicle and securely support it on jack stands.
  2. Remove the exhaust system components connected to the catalytic converter, starting with the bolts and hangers.
  3. Inspect the catalytic converter for blockages or physical damage.
  4. If replacement is necessary, install a new catalytic converter, ensuring proper alignment and secure all bolts to manufacturer specifications.
  5. Reassemble the exhaust system.

4. Final Checks

• Reconnect the battery.
• Start the engine and let it idle for a few minutes.
• Check for any exhaust leaks around the newly installed components.