how do I fix the P0420 code on my Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to ensure safety while working on electrical components.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Unplug the electrical connectors from both sensors.
3. Using an O2 sensor socket, carefully remove the sensors from the exhaust pipe.
4. Install the new sensors by screwing them in place and tightening them to the manufacturer’s specifications (typically 30-40 ft-lbs).
5. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

1. If the catalytic converter is confirmed to be damaged or clogged, remove it from the exhaust system.
2. Depending on the design, you may need to unbolt the exhaust pipe and remove any heat shields.
3. Install a new catalytic converter, ensuring proper alignment with exhaust flanges.
4. Tighten the bolts to the manufacturer’s specifications (typically 30-35 ft-lbs).
5. Reinstall any heat shields if removed.

4. Reset the OBD-II System

1. Reconnect the battery.
2. Use an OBD-II scanner to clear the P0420 code from the system.
3. Start the engine and let it run for a few minutes.