how to fix P0420 code on Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the battery to ensure safety during repairs.

2. Inspect and Replace Oxygen Sensors (if faulty)

1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Using an O2 sensor socket, carefully remove the sensors from the exhaust system.
3. Inspect the sensors for damage or carbon buildup. Replace if necessary.
4. Install new sensors, ensuring they are torqued to the manufacturer’s specifications (usually around 30 lb-ft).
5. Reconnect the battery.

3. Inspect and Replace the Catalytic Converter (if necessary)

1. If the catalytic converter is suspected to be faulty based on diagnostic results, remove it from the exhaust system.
2. Use a socket set to unbolt the catalytic converter from the exhaust pipes.
3. Inspect the catalytic converter for clogging or internal damage.
4. If replacement is required, install a new catalytic converter, ensuring all gaskets are replaced to prevent exhaust leaks.
5. Torque all bolts to the manufacturer’s specifications.

4. Clear the Codes

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