how to fix P0420 code Ford Explorer Fifth Generation (2011-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent any electrical shorts.
• Allow the vehicle to cool down if it has been recently driven.

2. Inspect and Replace Oxygen Sensors (if necessary)

• Tools Required: O2 sensor socket, wrench set, dielectric grease.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Remove the electrical connectors from both sensors.
  3. Use the O2 sensor socket to unscrew the sensors from their respective locations.
  4. Install new sensors and apply dielectric grease to the threads.
  5. Reconnect the electrical connectors securely.

3. Inspect Catalytic Converter

• Tools Required: Socket set, exhaust pipe cutter (if replacement is needed), jack and jack stands.
• Sub-steps:
  1. Visually inspect the catalytic converter for dents, cracks, or rust.
  2. If replacement is necessary, use a socket set to remove the bolts holding the catalytic converter in place.
  3. Cut the exhaust pipe if needed and prepare the new catalytic converter for installation.
  4. Install the new catalytic converter, ensuring all bolts are tightened to the manufacturer's specifications (typically around 25-30 ft-lbs).
  5. Reconnect any exhaust hangers or brackets that were removed.

4. Clear Codes and Test Drive

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the negative battery terminal.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
  3. Start the vehicle and allow it to reach operating temperature.
  4. Take the vehicle for a test drive to monitor performance and ensure no codes reappear.