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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to prevent any electrical issues.
• Allow the engine to cool down before working on the exhaust system.

2. Inspect and Clean Oxygen Sensors

• Tools Required: O2 sensor socket, penetrating oil, wire brush.
• Remove the upstream and downstream oxygen sensors using the O2 sensor socket.
• Inspect the sensors for damage or contamination; clean the connectors with a wire brush if necessary.
• Reinstall the sensors and ensure they are properly torqued according to specifications.

3. Check and Repair Exhaust Leaks

• Tools Required: Exhaust leak detector or smoke machine.
• Inspect the exhaust system using an exhaust leak detector or smoke machine to locate any leaks.
• If a leak is found, repair or replace the affected section of the exhaust system, ensuring all connections are tight and sealed.

4. Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if needed), new gaskets.
• Remove the catalytic converter by loosening the bolts at both ends using a socket set.
• Inspect the mounting points for rust or damage; replace if necessary.
• Install the new catalytic converter with new gaskets, ensuring the bolts are torqued to manufacturer specifications.

5. Reconnect Battery and Clear Codes

• Reconnect the battery terminals and ensure they are tight.
• Use the OBD-II scanner to clear the P0420 code and any other stored codes.
• Start the vehicle and let it idle for a few minutes to ensure proper function.