how to fix P0420 code on Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

• Gather necessary tools and parts.
• Park the vehicle on a level surface and engage the parking brake.
• Disconnect the battery negative terminal to ensure safety.

2. Inspect Oxygen Sensors

• Tools Required: OBD-II scanner, multimeter, socket set.
• Remove the upstream and downstream oxygen sensors using a socket wrench.
• Inspect the sensors for contamination or damage.
• Use a multimeter to check resistance: it should be within manufacturer specifications (typically around 14-18 ohms).
• Replace any malfunctioning sensors.

3. Examine the Catalytic Converter

• Tools Required: Jack stands, exhaust pipe cutter (if required), socket set.
• Inspect the catalytic converter for physical damage (dents, rust).
• Tap gently on the converter with a rubber mallet; listen for rattling sounds indicating internal damage.
• If damaged, remove the catalytic converter by unbolting it from the exhaust system.
• Install a new catalytic converter, ensuring proper alignment and sealing.

4. Reconnect Components

• Reinstall the upstream and downstream oxygen sensors onto the new catalytic converter.
• Reconnect the battery terminal.
• Clear the P0420 code using the OBD-II scanner.