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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent any electrical issues during the repair.
• Ensure the vehicle is on a level surface and secure it with jack stands if needed.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Using an O2 sensor socket, remove the upstream O2 sensor (usually before the catalytic converter).
  3. Install the new O2 sensor, ensuring it is tightened to the manufacturer’s specifications (typically around 30 lb-ft).
  4. Repeat the process for the downstream O2 sensor if it shows signs of failure.

Tools Required:

• OBD-II scanner
• O2 sensor socket
• Torque wrench

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Remove any heat shields covering the catalytic converter.
  2. Unbolt the catalytic converter from the exhaust pipes using a socket set.
  3. Inspect the old catalytic converter for any signs of damage or blockage.
  4. Install the new catalytic converter, ensuring proper alignment and sealing.
  5. Reattach any heat shields and ensure all bolts are torqued to the specified values.

Tools Required:

• Socket set
• Torque wrench
• Gasket scraper (if needed)