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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Safety goggles and gloves should be worn.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

1. Remove the Oxygen Sensors:
   • Use an O2 sensor socket to carefully remove the upstream and downstream oxygen sensors.
   • Inspect the threads and connectors for damage.
2. Install New Oxygen Sensors:
   • Apply anti-seize compound to the threads of the new sensors.
   • Tighten the sensors to the manufacturer's specifications (usually around 30-40 ft-lbs).
   • Reconnect the electrical connectors securely.

3. Inspect and Replace Catalytic Converter (if necessary)

1. Remove Exhaust Components:
   • Use a socket set to remove bolts connecting the exhaust manifold to the catalytic converter.
   • Disconnect any hangers or brackets securing the exhaust.
2. Install New Catalytic Converter:
   • Position the new catalytic converter in place.
   • Tighten all bolts to the specified torque (generally around 30-35 ft-lbs).
   • Reconnect exhaust hangers and any other components.
3. Check for Proper Sealing:
   • Ensure all gaskets and seals are in good condition to prevent leaks.

4. Clear Codes and Test

1. Reconnect Battery:
   • Reconnect the negative terminal of the battery.
2. Clear the P0420 Code:
   • Use the OBD-II scanner to clear the stored P0420 code.
3. Test Drive the Vehicle:
   • Drive the vehicle for a minimum of 20 minutes under various conditions to allow the system to reset.