how to fix P0420 code in my Toyota Camry XV70 (2018-2024)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.

Tools Required:

• OBD-II scanner
• Multimeter
• Socket set
• Torque wrench
• Jack and jack stands

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Disconnect the electrical connectors from both sensors.
3. Use a socket wrench to remove the sensors from the exhaust system.
4. Inspect the threads for damage. Replace if necessary.
5. Install new oxygen sensors, ensuring they are torqued to the manufacturer's specifications (typically around 30 lb-ft).
6. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

1. If the oxygen sensors are functioning correctly, inspect the catalytic converter.
2. Check for any signs of physical damage, such as dents or rust.
3. If damage is present, remove the catalytic converter by loosening the bolts securing it to the exhaust system.
4. Install a new catalytic converter, ensuring proper alignment and torque specifications (usually around 25 lb-ft).
5. Reconnect any exhaust components that were removed during the process.

4. System Reset

1. Reconnect the negative battery terminal.
2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
3. Start the engine and allow it to reach operating temperature.