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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical issues during repair.
• Ensure the vehicle is on a level surface and secure it with wheel chocks.

2. Inspect Oxygen Sensors

• Tools Required: O2 sensor socket, multimeter.
• Remove the upstream and downstream oxygen sensors from the exhaust system.
• Use a multimeter to test their resistance and response times. Replace any faulty sensors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust gasket.
• Remove the exhaust pipe and any brackets holding the catalytic converter.
• Inspect the catalytic converter for damage; if necessary, replace it with a new unit.
• Install the new catalytic converter, ensuring to use a new exhaust gasket and torque to manufacturer specifications.

4. Reinstall Oxygen Sensors

• After replacing the catalytic converter, reinstall the upstream and downstream oxygen sensors.
• Torque the sensors to manufacturer specifications to avoid damage.

5. Reset the Check Engine Light

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.