how to fix P0420 code on my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to prevent electrical issues during repairs.

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. Remove the Oxygen Sensors:
   • Use an oxygen sensor socket to carefully unscrew and remove both sensors.
   • Note their positions for correct reinstallation.
3. Install New Oxygen Sensors:
   • Apply anti-seize compound to the threads of the new sensors.
   • Screw in the new upstream and downstream sensors and tighten them to the manufacturer's specifications (typically around 30 ft-lbs).
4. Reconnect Electrical Connectors:
   • Ensure all electrical connectors are securely attached.

3. Inspect and Replace Catalytic Converter (if needed)

1. Assess the Catalytic Converter:
   • If the oxygen sensor replacement does not resolve the code, inspect the catalytic converter for blockages or damage.
2. Remove the Catalytic Converter:
   • Use a socket set to unbolt the catalytic converter from the exhaust system.
   • Ensure to support it appropriately to avoid damage.
3. Install New Catalytic Converter:
   • Position the new catalytic converter in place and secure it with new gaskets and bolts.
   • Torque the bolts to the manufacturer’s specifications (typically around 30 ft-lbs).

4. Reset the Engine Control Module (ECM)

1. Reconnect the Battery:
   • Reconnect the battery terminals securely.
2. Clear the Codes:
   • Use an OBD-II scanner to clear the P0420 code from the ECM.