how to fix Honda Pilot Third Generation (2016-present) check engine light P0420

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the negative battery terminal to ensure safety.

2. Inspect and Clean Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors.
2. Remove the oxygen sensors using an oxygen sensor socket.
3. Inspect the sensors for contamination or damage.
4. Clean the sensors carefully or replace them if necessary.
5. Reinstall the oxygen sensors, ensuring proper torque (typically around 30 ft-lbs).

3. Inspect Catalytic Converter

1. Visually inspect the catalytic converter for physical damage, such as dents or rust.
2. If damaged, remove the catalytic converter by loosening the bolts at both ends.
3. Replace with a new catalytic converter that meets OEM specifications.
4. Reinstall the new catalytic converter and tighten the bolts to manufacturer specifications (typically around 40 ft-lbs).

4. Reset the Check Engine Light

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