my Toyota Camry XV70 (2018-2024) has P0420 code, what does it mean

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to ensure safety during electrical work.

2. Inspect and Clean Sensors

• Remove the upstream and downstream oxygen sensors using a socket wrench.
• Clean the sensor connectors and inspect for damage.
• If sensors are faulty or contaminated, replace them with OEM parts.

3. Inspect and Replace Catalytic Converter (if necessary)

• Lift the vehicle and securely support it with jack stands.
• Remove the exhaust pipe bolts connecting to the catalytic converter using a socket set.
• Unscrew the bolts holding the catalytic converter in place.
• Install the new catalytic converter, ensuring proper alignment.
  • Torque specifications: 30 lb-ft for bolts.
• Reconnect the exhaust pipe and secure with bolts.

4. Reconnect Sensors

• Reinstall the upstream and downstream oxygen sensors, tightening them to manufacturer specifications.
• Reconnect the sensor wiring harnesses ensuring a secure fit.

5. Final Checks

• Reconnect the battery.
• Clear the error codes using the OBD-II scanner.
• Start the engine and allow it to reach operating temperature.