how to fix P0420 code in Toyota Tacoma N300 (2016-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors (usually near the exhaust manifold and after the catalytic converter).
  2. Disconnect the electrical connectors from both sensors.
  3. Use an O2 sensor socket to remove the faulty sensors.
  4. Install the new sensors and torque them to the manufacturer’s specifications (typically around 30 lb-ft).
  5. Reconnect the electrical connectors securely.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, cutting tool (if applicable), torque wrench.
• Sub-steps:
  1. Assess the condition of the catalytic converter; if damaged or clogged, proceed with replacement.
  2. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  3. Remove any mounting brackets securing the catalytic converter.
  4. Install the new catalytic converter, ensuring proper alignment with the exhaust system.
  5. Torque all bolts and connections to manufacturer’s specifications.

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use an OBD-II scanner to clear the P0420 code from the vehicle’s computer.
  3. Start the engine and allow it to reach operating temperature.
  4. Conduct a test drive to ensure the vehicle operates normally and the check engine light does not reappear.