how to fix P0420 code on Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shock.
• Raise the vehicle using a jack and secure it with jack stands.

2. Inspect and Replace O2 Sensors (if faulty)

• Tools Required: O2 sensor socket, wrench set, penetrating oil.
• Sub-steps:
  1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) O2 sensors.
  2. Apply penetrating oil to the O2 sensor threads and wait a few minutes.
  3. Disconnect the electrical connector from the O2 sensor.
  4. Use the O2 sensor socket to remove the faulty sensor.
  5. Install the new O2 sensor by threading it into the exhaust pipe and tightening it to manufacturer specifications (typically 30-40 ft-lbs).
  6. Reconnect the electrical connector to the new O2 sensor.

3. Replace the Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust gaskets, penetrating oil.
• Sub-steps:
  1. Remove the heat shield covering the catalytic converter if applicable.
  2. Disconnect the exhaust pipe from the catalytic converter by loosening the bolts and removing the flange.
  3. Remove any mounting bolts securing the catalytic converter to the exhaust system.
  4. Remove the old catalytic converter and replace it with a new one, ensuring proper alignment.
  5. Install new exhaust gaskets and torque all bolts to the manufacturer’s specifications (typically around 30-50 ft-lbs).
  6. Reinstall the heat shield if removed.