how to fix P0420 code in Ford Explorer Sixth Generation (2020-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety.
• Allow the engine to cool completely before starting work.

2. Inspect and Replace Oxygen Sensors (if necessary)

• Tools Required: O2 sensor socket, ratchet, and torque wrench.
• Instructions:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Disconnect the electrical connectors from both sensors.
  3. Use the O2 sensor socket and ratchet to remove the sensors from the exhaust system.
  4. Install new oxygen sensors and tighten them to the manufacturer's specified torque (usually around 30 lb-ft).
  5. Reconnect the electrical connectors.

3. Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, exhaust pipe cutter, and gasket sealant.
• Instructions:
  1. Raise the vehicle securely using jack stands.
  2. Use the exhaust pipe cutter to cut the exhaust pipe before and after the catalytic converter.
  3. Remove the old catalytic converter from the exhaust system.
  4. Clean the mating surfaces to ensure a good seal.
  5. Install the new catalytic converter, ensuring proper alignment with the exhaust system.
  6. Use gasket sealant as needed and tighten the bolts to the manufacturer's specifications (usually around 30 lb-ft).
  7. Lower the vehicle back to the ground.

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner.
• Instructions:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Test drive the vehicle under various conditions to ensure the problem has been resolved.