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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, jack stands, safety glasses, gloves.
• Disconnect the battery.
• Raise the vehicle securely on jack stands.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Detach the electrical connectors from both sensors.
  3. Use a socket wrench to remove the oxygen sensors from the exhaust system.
  4. Install new oxygen sensors, ensuring they are tightened to manufacturer specifications (typically around 30 lb-ft).
  5. Reconnect the electrical connectors.

3. Inspect and Replace the Catalytic Converter (if necessary)

• Sub-steps:
  1. Remove any heat shields that may obstruct access to the catalytic converter.
  2. Disconnect the exhaust pipes connected to the catalytic converter using a socket wrench.
  3. Remove the catalytic converter from the mounting brackets.
  4. Install the new catalytic converter, ensuring proper alignment with exhaust pipes.
  5. Tighten all bolts to the manufacturer's torque specifications (usually around 40-50 lb-ft).
  6. Reinstall heat shields.

4. Clear Error Codes

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear any stored error codes.
  3. Start the engine and let it idle for a few minutes.