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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on the vehicle.
• Lift the vehicle using a jack and secure it with jack stands for better access to the exhaust system.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors on the exhaust manifold and catalytic converter, respectively.
2. Disconnect the electrical connectors from both oxygen sensors.
3. Use an oxygen sensor socket to remove the sensors from the exhaust system.
4. Install the new oxygen sensors and torque to manufacturer specifications (typically around 30 ft-lbs).
5. Reconnect the electrical connectors to the sensors.

3. Examine and Replace the Catalytic Converter

1. Inspect the catalytic converter for physical damage or signs of clogging.
2. If replacement is necessary, unbolt the catalytic converter from the exhaust system.
3. Remove any heat shields or brackets securing the converter.
4. Install the new catalytic converter, ensuring proper alignment.
5. Torque the bolts to manufacturer specifications (usually around 40-50 ft-lbs).
6. Reattach any heat shields or brackets removed earlier.

4. Clear Codes and Test Drive

1. Reconnect the battery.
2. Use the OBD-II scanner to clear the P0420 code from the system.
3. Start the engine and allow it to reach operating temperature.
4. Take the vehicle for a test drive to ensure the check engine light does not reappear and the vehicle runs smoothly.