what does error code P0420 mean for my Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

• Gather necessary tools and safety equipment.
• Disconnect the vehicle battery to prevent electrical shocks.
• Allow the engine to cool completely before working on the exhaust system.

2. Inspect Oxygen Sensors

• Remove the upstream (pre-catalytic converter) oxygen sensor using a socket wrench.
• Inspect the sensor for damage and test it with a multimeter for proper voltage readings.
• If faulty, replace the oxygen sensor with a new OEM part.

3. Inspect and Test Catalytic Converter

• Remove the heat shield if necessary using a socket set.
• Measure the temperature at the inlet and outlet of the catalytic converter using a thermometer or infrared thermometer. The outlet temperature should be approximately 100-150°F higher than the inlet temperature.
• If the temperature difference is not sufficient, replace the catalytic converter with a new OEM unit.

4. Reassemble Components

• Reinstall any heat shields removed during inspection.
• Reconnect the upstream oxygen sensor after ensuring it is functioning correctly.
• Reconnect the vehicle battery.

5. Clear Error Codes

• Use the OBD-II scanner to clear the P0420 error code from the ECM.
• Start the engine and allow it to reach operating temperature, ensuring no codes return.