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

Solution

1. Preparation

• Tools Required: OBD-II scanner, socket set, torque wrench, jack and jack stands, exhaust leak detector.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect Exhaust System

• Sub-steps:
  1. Raise the vehicle using a jack and secure with jack stands.
  2. Visually inspect the entire exhaust system from the manifold to the catalytic converter for leaks or damage.
  3. Use an exhaust leak detector to identify any leaks.

3. Check Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Disconnect the electrical connectors from both sensors.
  3. Using a multimeter, check the resistance and voltage readings of both sensors according to manufacturer specifications.
  4. Replace any faulty sensors.

4. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Remove the bolts securing the catalytic converter to the exhaust manifold and pipe using the socket set.
  2. Inspect the catalytic converter for any signs of clogging or damage.
  3. If necessary, replace the catalytic converter with a new, OEM-quality unit.
  4. Reinstall the catalytic converter and secure it with bolts, applying the manufacturer-specified torque.

5. Clear Codes and Reconnect Battery

• Sub-steps:
  1. Reconnect the battery terminals.
  2. Use the OBD-II scanner to clear the P0420 trouble code.
  3. Start the engine and allow it to reach operating temperature.