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

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the vehicle battery to prevent electrical shorts.
• Allow the engine to cool completely before working on the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Disconnect the electrical connectors from each sensor.
  3. Use an O2 sensor socket to remove the sensors from the exhaust manifold and catalytic converter.
  4. Install new oxygen sensors in their respective locations and connect the electrical connectors.
• Tools Required: O2 sensor socket, ratchet wrench.

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Remove the exhaust pipes connected to the catalytic converter using a socket set.
  2. Support the catalytic converter with a jack or support stand.
  3. Unbolt the catalytic converter from the exhaust system and remove it.
  4. Install the new catalytic converter and secure it with bolts to the exhaust system.
  5. Reconnect the exhaust pipes and ensure all connections are tight.
• Tools Required: Socket set, jack or stands.

4. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the vehicle battery.
  2. Use the OBD-II scanner to clear the P0420 trouble code from the system.
  3. Start the engine and let it idle for a few minutes.
  4. Take the vehicle for a test drive to ensure the check engine light does not reappear.
• Tools Required: OBD-II scanner.