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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical systems.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, penetrating oil.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Apply penetrating oil to the sensor threads and allow it to soak for a few minutes.
  3. Disconnect the electrical connectors from the sensors.
  4. Using the O2 sensor socket, remove the sensors by turning counterclockwise.
  5. Install new oxygen sensors by threading them in and tightening to the manufacturer's torque specifications (typically around 30 lb-ft).
  6. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust gasket, possibly a saw or cutting tool.
• Sub-steps:
  1. Locate the catalytic converter and check for physical damage or blockage.
  2. Remove the exhaust pipes connected to the catalytic converter using a socket set.
  3. If the converter is damaged, remove it by cutting or unbolting it, depending on the design.
  4. Install the new catalytic converter, ensuring proper orientation and alignment.
  5. Use a new exhaust gasket for sealing and tighten all bolts to the specified torque.

4. Clear Error Codes

• Tools Required: OBD-II scanner.
• Sub-steps:
  1. Reconnect the battery.
  2. Use an OBD-II scanner to clear the P0420 code from the vehicle's computer.

5. Final Inspection

• Tools Required: None.
• Sub-steps:
  1. Start the engine and let it idle for a few minutes.
  2. Listen for any unusual noises and check for exhaust leaks around the replaced components.