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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and turn off the engine.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors (usually before and after the catalytic converter).
2. Use a socket wrench to carefully remove the oxygen sensors.
3. Inspect the sensors for damage; replace if necessary.
4. Install new oxygen sensors and torque to manufacturer specifications (usually around 30 ft-lbs).
5. Reconnect the battery.

3. Inspect and Replace the Catalytic Converter

1. Lift the vehicle safely using jack stands.
2. Remove the exhaust pipes connected to the catalytic converter using a wrench or socket set.
3. If applicable, unbolt heat shields or hangers to free the catalytic converter.
4. Inspect for physical damage; if found, install a new catalytic converter.
5. Torque bolts to manufacturer specifications (usually around 40 ft-lbs).
6. Reconnect exhaust pipes and heat shields.

4. Clear the Trouble Codes

1. Use an OBD-II scanner to clear the P0420 code from the vehicle's computer.
2. Ensure the vehicle is in a safe environment and start the engine.