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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the downstream oxygen sensor (after the catalytic converter).
  1. Use an O2 sensor socket to unscrew the sensor.
  2. Install the new sensor and torque it to manufacturer specifications (usually around 30-40 ft-lbs).
• Repeat for the upstream oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, jack and jack stands, exhaust clamp tool
• Raise the vehicle and secure it on jack stands.
• Locate the catalytic converter and inspect for damage.
• If replacement is needed:
  1. Remove exhaust clamps securing the catalytic converter.
  2. Carefully detach the catalytic converter from the exhaust system.
  3. Install the new catalytic converter, ensuring all flanges and gaskets are sealed properly.
  4. Reattach exhaust clamps securely.

4. Clear Diagnostic Codes

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code.
• Start the engine and perform a short test drive to see if the code returns.