how to fix the P0420 code in my Honda Pilot Third Generation (2016-present)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the vehicle.
• Raise the vehicle securely using jack stands.

2. Inspect and Replace Oxygen Sensors (if necessary)

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Using a socket wrench, disconnect the electrical connectors from each sensor.
  3. Remove the sensors using an oxygen sensor socket.
  4. Install new sensors by reversing the removal steps, ensuring not to overtighten.
• Tools Required: Oxygen sensor socket, wrench set, multimeter (for testing).

3. Test and Replace Catalytic Converter (if necessary)

• Sub-steps:
  1. Use an infrared thermometer to measure the temperature of the exhaust before and after the catalytic converter.
  2. If the temperature difference is less than 100°F, the catalytic converter may be faulty.
  3. Remove the exhaust pipes connected to the catalytic converter using a socket set.
  4. Unbolt the catalytic converter from its mounts and remove it.
  5. Install the new catalytic converter and ensure all connections are tight.
• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if necessary).

4. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
  3. Start the vehicle and monitor the check engine light during a test drive.
• Tools Required: OBD-II scanner.