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

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.
• Tools Required: OBD-II scanner, socket set, multimeter, torque wrench, and safety glasses.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors in the exhaust system.
  2. Disconnect the electrical connectors from both sensors.
  3. Use a socket wrench to carefully remove the sensors from the exhaust pipe.
  4. Install new oxygen sensors, ensuring they are torqued to manufacturer specifications (usually around 30 lb-ft).
  5. Reconnect the electrical connectors to the new sensors.

3. Inspect and Clean Catalytic Converter

• Sub-steps:
  1. If no damage is found, attempt to clean the catalytic converter using a specialized cleaner or by running a fuel additive designed for this purpose.
  2. If cleaning does not resolve the issue, remove the catalytic converter for inspection.
  3. Inspect for any signs of physical damage or blockage.
  4. If damaged, replace with a new catalytic converter, ensuring proper fitment and securing with appropriate exhaust gaskets and hardware.

4. Reassemble and Test

• Sub-steps:
  1. Reassemble any components that were removed during inspection and repair.
  2. Reconnect the battery.
  3. Clear the P0420 code using the OBD-II scanner.
  4. Start the engine and allow it to reach operating temperature.