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

Solution

1. Preparation

• Gather the necessary tools and parts.
• Disconnect the battery to prevent any electrical shorts.
• Allow the engine to cool down before starting work.

2. Inspect Oxygen Sensors

• Tools Required: OBD-II scanner, multimeter
• Check the upstream (pre-catalytic converter) oxygen sensor.
  • Remove the sensor using an oxygen sensor socket.
  • Inspect the sensor for damage or contamination.
  • Test the sensor's voltage output while the engine is running (should fluctuate between 0.1 and 0.9 volts).
• If faulty, replace the oxygen sensor:
  • Apply anti-seize compound to the threads of the new sensor.
  • Install the new sensor and torque to manufacturer specifications (typically around 30 ft-lbs).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack stands, exhaust gasket
• Raise the vehicle and secure it on jack stands.
• Remove any heat shields if applicable.
• Disconnect the exhaust pipes from the catalytic converter.
• Remove the catalytic converter by unbolting it from the exhaust manifold and the muffler.
• Inspect the old catalytic converter for blockages or physical damage.
• Install the new catalytic converter:
  • Align the new converter with the exhaust system.
  • Use new gaskets and bolts as necessary.
  • Torque all connections to manufacturer specifications.

4. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use an OBD-II scanner to clear the P0420 code.
• Start the engine and allow it to reach operating temperature.