how to fix P0420 code on my Toyota RAV4 XA40 (2013-2018)

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the vehicle's 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. Using a socket wrench, carefully unscrew the oxygen sensors from their respective locations.
3. Compare the readings of the new sensors with the old ones to ensure compatibility.
4. Install the new oxygen sensors in the reverse order of removal, ensuring they are tightened to the manufacturer's specifications (usually around 30 Nm).
5. Reconnect the vehicle’s battery.

3. Inspect and Replace Catalytic Converter (if necessary)

1. Using a socket set, unbolt the catalytic converter from the exhaust system.
2. Carefully remove the catalytic converter from its mounting.
3. Install the new catalytic converter, ensuring proper alignment with the exhaust pipes.
4. Bolt the catalytic converter in place, tightening to manufacturer specifications (usually around 50 Nm).
5. Reconnect any exhaust hangers or brackets that were removed during installation.

4. Clear Fault Codes

1. Reconnect the battery.
2. Use an OBD-II scanner to clear any fault codes from the system.
3. Start the engine and allow it to reach operating temperature.