how to fix P0420 in Honda Pilot YF4 (2023-Present)

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the battery to ensure safety.
• Lift the vehicle using a jack and secure it with jack stands.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
2. Disconnect the electrical connectors from both sensors.
3. Use an oxygen sensor socket to remove the sensors from the exhaust system.
4. Install new oxygen sensors by threading them into their respective locations and tightening them to manufacturer specifications (typically 30-40 lb-ft).
5. Reconnect the electrical connectors to the oxygen sensors.

3. Inspect and Replace the Catalytic Converter

1. If the oxygen sensors are functioning correctly, locate the catalytic converter.
2. Remove any bolts or clamps securing the catalytic converter to the exhaust system.
3. Carefully remove the catalytic converter from its position.
4. Install the new catalytic converter, ensuring that it is seated properly.
5. Secure it with the bolts or clamps to the manufacturer’s torque specifications.

4. Clear the Error Codes

1. Reconnect the battery.
2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
3. Start the engine and let it reach normal operating temperature.