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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent any electrical issues.
• Allow the engine to cool completely before starting work.

2. Inspect and Replace Oxygen Sensors

1. Remove the upstream oxygen sensor:
   • Locate the upstream oxygen sensor (usually before the catalytic converter).
   • Use an oxygen sensor socket to unscrew and remove it.
2. Install the new upstream oxygen sensor:
   • Apply anti-seize compound on the threads of the new sensor.
   • Screw it in by hand and tighten it with the sensor socket (usually to a torque of 30 ft-lbs).
3. Repeat for the downstream oxygen sensor (if needed):
   • Follow the same steps as above for the downstream sensor located after the catalytic converter.

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

1. Remove the exhaust components:
   • Support the exhaust with jack stands.
   • Unbolt any brackets or hangers that secure the exhaust system.
2. Remove the catalytic converter:
   • Loosen and remove the bolts connecting the catalytic converter to the exhaust manifold and exhaust pipe.
   • Carefully take out the catalytic converter.
3. Install the new catalytic converter:
   • Position the new catalytic converter in place.
   • Secure it with the original or new bolts, ensuring they are tightened to manufacturer specifications (typically 30-40 ft-lbs).
4. Reattach the exhaust components:
   • Reconnect any hangers or brackets that were removed.

4. Reset the Engine Control Module (ECM)

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code from the ECM.