how to fix the P0420 code in my Toyota RAV4 XA50 (2019-2024)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal for safety.
• Raise the vehicle using jack stands if working underneath.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream oxygen sensor:
  1. Locate the upstream oxygen sensor (before the catalytic converter).
  2. Use the O2 sensor socket to unscrew and remove the sensor.
• Install the new oxygen sensor:
  1. Apply anti-seize compound to the threads of the new oxygen sensor.
  2. Hand-tighten the sensor into the exhaust pipe and then torque it to the manufacturer's specification (usually around 30 ft-lbs).
• Repeat the process for the downstream oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust hanger removal tool
• Remove the catalytic converter:
  1. Loosen and remove the bolts securing the catalytic converter to the exhaust pipe using a socket set.
  2. Detach any hangers using the exhaust hanger removal tool.
• Install the new catalytic converter:
  1. Position the new catalytic converter in place, ensuring proper alignment.
  2. Torque the bolts to the manufacturer's specification (typically around 30-35 ft-lbs).
  3. Reattach the exhaust hangers securely.

4. Clear Codes and Test

• Tools Required: OBD-II scanner
• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the vehicle’s computer.
• Start the engine and allow it to reach operating temperature.