how to fix P0420 code on Ford F-150 13th Generation (2015-2020)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shock.
• Ensure the vehicle is on a flat surface and secure it with jack stands if elevated.

2. Inspect and Replace Oxygen Sensors (if necessary)

• Tools Required: O2 sensor socket, wrench set, penetrating oil.
• Sub-steps:
  1. Locate the upstream (before the catalytic converter) and downstream (after the catalytic converter) oxygen sensors.
  2. Apply penetrating oil to the sensor threads to facilitate removal.
  3. Disconnect the electrical connector from the sensor.
  4. Use the O2 sensor socket to remove the upstream sensor first, followed by the downstream sensor if needed.
  5. Install the new sensors, ensuring a proper torque of approximately 30 lb-ft.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, cutting tool (if necessary for pipes), exhaust gasket, torque wrench.
• Sub-steps:
  1. Disconnect the exhaust pipes from the catalytic converter using a socket set.
  2. Remove any mounting bolts and brackets securing the catalytic converter.
  3. If the converter is clogged or damaged, replace it with a new unit, ensuring that it matches OEM specifications.
  4. Reinstall the exhaust pipes and secure them with new gaskets and bolts, tightening to the manufacturer’s specifications (typically around 25 lb-ft).

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the battery after all repairs are completed.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle’s computer.
  3. Perform a test drive for at least 15-20 miles to ensure the vehicle operates normally and check for reoccurrence of the code.