how to fix P0420 code on my 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 battery to prevent electrical issues.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
  2. Use an O2 sensor socket to remove the faulty oxygen sensors.
  3. Install new oxygen sensors (ensure to apply anti-seize compound if required) and torque to manufacturer's specifications (typically around 30 lb-ft).

3. Inspect and Replace the Catalytic Converter

• Sub-steps:
  1. Locate the catalytic converter and check for any signs of damage or clogging.
  2. Remove the mounting bolts using a socket set and an appropriate wrench.
  3. Carefully detach the catalytic converter from the exhaust system.
  4. Install the new catalytic converter, ensuring proper alignment and sealing.
  5. Torque the bolts to manufacturer specifications (typically around 40 lb-ft).

4. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the negative battery terminal securely.
  2. Use an OBD-II scanner to clear the P0420 code from the vehicle’s computer.