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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool down completely.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
• Use an O2 sensor socket to remove the faulty sensor.
• Install the new sensor, ensuring it is securely tightened (typically to manufacturer specifications around 30 ft-lbs).
• Reconnect the electrical connector.

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

• Remove the exhaust system components that are obstructing access to the catalytic converter (e.g., heat shields, exhaust pipes).
• Unbolt the catalytic converter from the exhaust manifold and the exhaust pipe using a socket wrench.
• Install the new catalytic converter, ensuring proper alignment and secure bolting (recommended torque specifications around 30-40 ft-lbs).
• Reinstall any exhaust components removed in the process.

4. Clear Codes and Reconnect Battery

• Reconnect the battery terminal.
• Use an OBD-II scanner to clear the P0420 code.
• Start the vehicle and allow it to reach operating temperature.