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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, multimeter.
• Disconnect the electrical connectors from both the upstream and downstream oxygen sensors.
• Use the O2 sensor socket to remove the sensors from the exhaust manifold and the catalytic converter.
• Test the resistance and voltage of the sensors using a multimeter, replacing any faulty sensors with new ones.
• Install the new sensors and reconnect the electrical connectors.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust hanger removal tool.
• Remove the exhaust pipes connected to the catalytic converter by loosening the clamps or bolts.
• Use the exhaust hanger removal tool to detach the converter from its hangers.
• Inspect the catalytic converter for any signs of damage or blockage.
• If faulty, install a new catalytic converter and ensure it is properly aligned.
• Reattach the exhaust pipes and tighten the clamps/bolts to the manufacturer’s torque specifications.

4. Clear the Codes and Test Drive

• Reconnect the battery and use an OBD-II scanner to clear the P0420 code.
• Start the engine and let it idle for a few minutes before taking the vehicle for a test drive to ensure the problem is resolved.