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

Solution

1. Preparation

• Gather tools and parts required.
• Disconnect the battery to ensure safety.
• Raise the vehicle using a jack and secure with jack stands.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
2. Use an O2 sensor socket to carefully remove the upstream O2 sensor.
3. Install the new upstream O2 sensor and tighten it to the manufacturer's specified torque (typically around 30 lb-ft).
4. Repeat for the downstream O2 sensor if it shows signs of failure.
5. Reconnect the electrical connectors for both sensors.

3. Inspect and Replace Catalytic Converter

1. Remove the exhaust pipes connected to the catalytic converter using a socket set.
2. Unbolt the catalytic converter from the exhaust manifold and the exhaust pipe.
3. Install the new catalytic converter, ensuring proper fitment.
4. Torque all bolts to the manufacturer's specifications (typically around 25-30 lb-ft).
5. Reconnect the exhaust pipes and ensure all seals are properly seated.

4. Clear Error Codes

1. Reconnect the battery.
2. Use an OBD-II scanner to clear the P0420 code.
3. Start the engine and allow it to reach operating temperature.