how to fix P0420 code on Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shocks.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the pre-catalytic converter oxygen sensor:
  • Locate the sensor in the exhaust manifold.
  • Use the O2 sensor socket to unscrew it counterclockwise.
• Install the new sensor:
  • Apply anti-seize compound to the threads of the new sensor.
  • Screw it in by hand, then tighten it with a torque wrench to the manufacturer’s specifications (usually around 30-40 lb-ft).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands
• Raise the vehicle securely using a jack and jack stands.
• Remove the exhaust pipe connected to the catalytic converter:
  • Loosen the bolts connecting the exhaust pipe to the catalytic converter.
  • Carefully remove the pipe from the catalytic converter.
• Remove the catalytic converter:
  • Unscrew the bolts holding the converter in place.
  • Remove the converter from the exhaust system.
• Install the new catalytic converter:
  • Position the new catalytic converter and secure it with bolts.
  • Reattach the exhaust pipe and tighten all connections.

4. Final Steps

• Reconnect the negative battery terminal.
• Start the engine and let it idle for a few minutes to check for exhaust leaks.
• Clear the error codes using the OBD-II scanner.