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

Solution

1. Preparation

• Gather necessary tools and parts.
• Make sure the vehicle is on a level surface and the engine is cool.
• Disconnect the battery to prevent any electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Disconnect the electrical connectors from both sensors.
  3. Use an oxygen sensor socket to remove the sensors from the exhaust system.
  4. Install new oxygen sensors, tightening them to the manufacturer's specified torque (usually around 30 ft-lbs).
  5. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Sub-steps:
  1. Locate the catalytic converter in the exhaust system.
  2. Use a wrench to disconnect the exhaust clamps and bolts securing the catalytic converter.
  3. Remove the catalytic converter from the exhaust system.
  4. Install the new catalytic converter, ensuring proper alignment and sealing.
  5. Reattach the exhaust clamps and bolts, torquing to manufacturer specifications.

4. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the engine and allow it to reach operating temperature.
  4. Take the vehicle for a test drive to monitor for any reoccurrence of the check engine light.