how to fix P0420 code in Genesis G70 IG (2017-2023)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shock and ensure safety.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream and downstream oxygen sensors using the O2 sensor socket.
• Inspect the sensors for damage or contamination.
• If faulty, replace them with new sensors, ensuring to torque them to manufacturer specifications (typically around 30-40 ft-lbs).

3. Check and Replace the Catalytic Converter

• Tools Required: Socket set, torch, exhaust pipe cutter
• Remove the exhaust system components leading to the catalytic converter.
  • Use the socket set to unbolt any flanges.
  • If necessary, cut the exhaust pipe using an exhaust pipe cutter.
• Inspect the catalytic converter for blockage or damage.
• If required, replace the catalytic converter with an OEM or approved aftermarket part. Ensure all gaskets and seals are new.
• Reinstall the exhaust system components, tightening bolts to the manufacturer's torque specifications.

4. Clear Codes and Test

• Reconnect the battery and use the OBD-II scanner to clear the P0420 code.
• Start the engine and allow it to reach operating temperature.
• Perform a road test to ensure the check engine light does not reappear.