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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the battery to avoid electrical shock.
• Allow the engine to cool before starting work on the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream oxygen sensor:
  • Locate the upstream O2 sensor on the exhaust manifold.
  • Use the O2 sensor socket to unscrew the sensor.
• Install the new upstream O2 sensor:
  • Apply anti-seize compound to the threads of the new sensor.
  • Torque to manufacturer's specifications (usually around 30 lb-ft).
• Repeat the process for the downstream oxygen sensor.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, cutting tool (if necessary), gaskets, torque wrench
• Remove the catalytic converter:
  • Loosen and remove the bolts securing the catalytic converter to the exhaust system.
  • If necessary, cut the exhaust pipe to remove the old catalytic converter.
• Install the new catalytic converter:
  • Position the new catalytic converter and secure it with bolts.
  • Use new gaskets to prevent exhaust leaks.
  • Torque bolts to manufacturer's specifications (usually around 40 lb-ft).

4. Clear the Trouble Codes

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code from the vehicle’s computer.

5. Test Drive

• Start the engine and let it warm up.
• Take the vehicle for a test drive to ensure the check engine light does not reappear.