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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery (negative terminal).
• Allow the exhaust system to cool before starting work.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, multimeter
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Disconnect the electrical connectors from both sensors.
  3. Use an O2 sensor socket to remove the sensors.
  4. Install the new oxygen sensors in the reverse order, ensuring they are tightened to the manufacturer’s specifications (typically around 30-35 ft-lbs).
  5. Reconnect the electrical connectors.

3. Inspect Catalytic Converter

• Tools Required: Jack and jack stands, socket set, infrared thermometer
• Sub-steps:
  1. Safely lift the vehicle and secure it with jack stands.
  2. Inspect the catalytic converter and exhaust pipes for signs of damage or leaks.
  3. If no visible damage is found, proceed to test the converter temperature.
  4. Use an infrared thermometer to measure the inlet and outlet temperatures of the catalytic converter. A significant temperature difference (at least 100°F) indicates proper function.
  5. If the catalytic converter is damaged or not functioning, remove it using a socket set and replace it with a new unit.

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Reconnect the vehicle battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the vehicle and perform a test drive to ensure the issue has been resolved.