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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, exhaust backpressure gauge.
• Disconnect the battery negative terminal to ensure safety.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Disconnect the electrical connectors from both sensors.
  3. Use a socket wrench to remove the sensors from the exhaust pipe.
  4. Install new oxygen sensors, applying anti-seize compound to the threads if required.
  5. Torque the sensors to the manufacturer's specifications (typically around 30 lb-ft).
  6. Reconnect the electrical connectors.

3. Inspect and Replace the Catalytic Converter

• Sub-steps:
  1. Locate the catalytic converter in the exhaust system.
  2. Remove any heat shields or protective covers if present.
  3. Use a socket set to unbolt the catalytic converter from the exhaust pipes.
  4. Inspect the old catalytic converter for damage or clogging.
  5. Install the new catalytic converter, ensuring correct alignment and fit.
  6. Torque all bolts to the manufacturer’s specifications (typically around 40 lb-ft).
  7. Reinstall any heat shields or covers.

4. Clear Error Codes

• After completing repairs, reconnect the battery terminal.
• Use the OBD-II scanner to clear the P0420 code.