how to fix the P0420 code on my Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

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

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the oxygen sensors (usually found before and after the catalytic converter).
  2. Remove the electrical connectors from the oxygen sensors.
  3. Use an oxygen sensor socket to remove the sensors from the exhaust system.
  4. Install new oxygen sensors, ensuring they are torqued to the manufacturer's specifications (typically around 30 lb-ft).
  5. Reconnect the electrical connectors to the new sensors.

3. Inspect and Replace the Catalytic Converter

• Sub-steps:
  1. Remove any heat shields or brackets securing the catalytic converter.
  2. Use a socket set to remove the bolts securing the catalytic converter to the exhaust system.
  3. Carefully lower the catalytic converter and inspect for physical damage or blockage.
  4. If defective, install a new catalytic converter, aligning it properly with the exhaust pipes.
  5. Torque the bolts to the manufacturer's specifications (usually around 25 lb-ft).
  6. Reattach any heat shields or brackets removed earlier.

4. Clear Codes and Test

• Sub-steps:
  1. Reconnect the battery.
  2. Use an OBD-II scanner to clear the P0420 code from the system.
  3. Start the engine and allow it to reach operating temperature.
  4. Take the vehicle for a test drive to ensure the check engine light does not reappear.