how to fix P0420 code on my Toyota RAV4 XA40 (2013-2018)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety during repairs.

2. Oxygen Sensor Inspection

• Tools Required: O2 sensor socket, multimeter
• Remove the upstream oxygen sensor (before the catalytic converter) using the O2 sensor socket.
• Test the sensor's resistance and voltage output according to manufacturer specifications. Replace if faulty.

3. Catalytic Converter Inspection

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if necessary)
• Visually inspect the catalytic converter for any physical damage or a rattling noise.
• If damaged, remove the catalytic converter by unbolting it from the exhaust system.
  • Use the socket set for bolts and ensure to note the torque specifications for reinstallation.
• Install the new catalytic converter, ensuring proper alignment and sealing.

4. Reinstall Oxygen Sensors

• Reinstall the upstream oxygen sensor and check the torque specifications; usually around 30 ft-lbs.
• If replaced, install the new downstream oxygen sensor using the same procedure.

5. Reset the Engine Control Module (ECM)

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