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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Ensure the vehicle is on a level surface and secure it with wheel chocks.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors: Identify the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Disconnect the Sensors: Carefully unplug the electrical connectors from both sensors.
3. Remove the Sensors: Use an oxygen sensor socket to unscrew and remove the sensors from their respective locations.
4. Install New Sensors: Apply anti-seize compound to the threads of the new sensors, then install them by hand to avoid cross-threading. Tighten to manufacturer specifications (usually around 30-45 lb-ft).

3. Inspect and Replace the Catalytic Converter

1. Check for Exhaust Leaks: Examine the exhaust piping and gaskets for any leaks. Repair or replace as needed.
2. Remove Exhaust Components: If the catalytic converter is faulty, remove any exhaust hangers or brackets using a socket set. Then, disconnect the catalytic converter from the exhaust system.
3. Install New Catalytic Converter: Position the new catalytic converter in place, securing it with the appropriate gaskets and hardware.
4. Reattach Exhaust Components: Reattach any exhaust pipes or components, ensuring all bolts are tightened to the specified torque values.

4. Clear Diagnostic Codes

• Reconnect the battery and use the OBD-II scanner to clear the P0420 code.

5. Test Drive

• Conduct a test drive to monitor the system for proper operation and to ensure the check engine light does not reappear.