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

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the negative battery terminal to prevent electrical shock.
• Allow the engine to cool completely before starting work.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Use the O2 sensor socket to remove the upstream (pre-catalytic converter) oxygen sensor.
  3. Check the condition of the sensor; if it appears damaged or dirty, replace it with a new one.
  4. Repeat the process for the downstream (post-catalytic converter) oxygen sensor.
  5. Torque the new sensors to the manufacturer's specifications (usually around 30-40 lb-ft).

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, exhaust gasket, jack stands, torque wrench.
• Sub-steps:
  1. Lift the vehicle using jack stands for access to the undercarriage.
  2. Disconnect the exhaust pipes from the catalytic converter using the socket set.
  3. Remove the catalytic converter mounting bolts and the exhaust gasket.
  4. Inspect the old catalytic converter for signs of blockage or damage.
  5. Install the new catalytic converter with a new exhaust gasket, and torque the bolts to the manufacturer's specifications.
  6. Reconnect the exhaust pipes ensuring a secure fit.

4. Clear Error Codes

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
  3. Start the engine and let it idle for a few minutes.