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

Solution

1. Preparation

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

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench
• Remove the pre-catalytic O2 sensor using the O2 sensor socket.
• Inspect the sensor for any signs of damage or contamination; replace if necessary.
• Install the new O2 sensor and torque to the manufacturer's specifications (typically around 30 lb-ft).
• Repeat the process for the post-catalytic O2 sensor if it was found faulty.

3. Replace Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if necessary)
• Remove the exhaust pipe bolts connecting to the catalytic converter using a socket set.
• Carefully detach the catalytic converter from the exhaust system; use an exhaust pipe cutter if welded.
• Install the new catalytic converter by reversing the removal process. Ensure all connections are tight and properly aligned.
• Torque the bolts to the manufacturer's specifications (typically around 40-50 lb-ft).

4. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear the P0420 code from the vehicle’s memory.
• Ensure all tools are removed from the engine bay.