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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery to avoid electrical issues.
• Allow the exhaust system to cool down before working on it.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, multimeter.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Remove the connectors from each oxygen sensor.
  3. Use the O2 sensor socket to unscrew the sensors from the exhaust system.
  4. Inspect the old sensors for carbon buildup or damage.
  5. Install new oxygen sensors, ensuring proper torque (typically 30-40 ft-lbs).
  6. Reconnect the sensor connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust gasket.
• Sub-steps:
  1. Remove any heat shields covering the catalytic converter.
  2. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  3. Inspect the catalytic converter visually for damage or clogging.
  4. Replace the catalytic converter with a new unit if it is damaged or not functioning correctly.
  5. Reassemble the exhaust system, ensuring all bolts are torqued to manufacturer specifications (usually 20-25 ft-lbs).
  6. Install a new exhaust gasket to prevent leaks.

4. Clear Codes and Test

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the vehicle's battery.
  2. Use an OBD-II scanner to clear the P0420 code from the system.
  3. Start the engine and let it run to check for any reoccurrence of the code.