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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Replace Faulty Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, and extension.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Use the O2 sensor socket to carefully unscrew and remove the faulty sensors.
  3. Install the new oxygen sensors by threading them into place and tightening to manufacturer specifications (typically 30-35 ft-lbs).
  4. Reconnect the electrical connectors to the sensors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, exhaust pipe cutter (if needed).
• Sub-steps:
  1. Lift the vehicle and secure it on jack stands.
  2. Remove any heat shields covering the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter using a socket set or exhaust pipe cutter.
  4. Remove the old catalytic converter from its mounting points.
  5. Install the new catalytic converter by securing it in place and reconnecting the exhaust pipes.
  6. Reinstall any heat shields previously removed.

4. Clear Codes and Reconnect Battery

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.