how to fix the P0420 code on my Ford F-150 Fourteenth Generation (2021-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to avoid electrical shorts.
• Raise the vehicle securely using jack stands if necessary.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  • Locate the upstream and downstream oxygen sensors.
  • Use an oxygen sensor socket to remove the faulty sensors.
  • Install new oxygen sensors, ensuring they are properly torqued to manufacturer's specifications (usually around 30 Nm).
  • Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  • Remove the exhaust pipe connected to the catalytic converter using a socket set (note any bolts that may require specific torque values, typically around 25-30 Nm).
  • Carefully unbolt the catalytic converter from its mounting points.
  • Install the new catalytic converter, ensuring a proper fit and sealing.
  • Reattach the exhaust pipe, checking that all connections are secure and leak-free.

4. Clear Codes and Test Drive

• Sub-steps:
  • Reconnect the vehicle battery.
  • Use the OBD-II scanner to clear the P0420 code.
  • Perform a test drive to allow the vehicle’s computer to run the diagnostic checks again.