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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to prevent electrical shorts.
• Raise the vehicle using a jack and secure it with jack stands for safety.

2. Inspect and Replace Oxygen Sensors

• Locate the upstream and downstream oxygen sensors on the exhaust system.
• Using a socket wrench, carefully remove the sensors.
• Inspect the sensors for damage, carbon buildup, or corrosion.
• If faulty, replace with new sensors (ensure they are the correct type for your vehicle).
• Reconnect the wiring harness to the new sensors.

3. Inspect and Replace the Catalytic Converter

• If the catalytic converter is determined to be faulty, begin by removing any components obstructing access, such as heat shields or exhaust hangers.
• Using a socket set, unbolt the catalytic converter from the exhaust manifold and exhaust pipe.
• Replace with a new catalytic converter, ensuring it is compatible with the vehicle's specifications.
• Torque the bolts to the manufacturer’s specifications (typically around 25-30 lb-ft).
• Reinstall any previously removed heat shields or components.

4. Reconnect Battery and Clear Codes

• Reconnect the negative terminal of the battery.
• Use an OBD-II scanner to clear the P0420 code from the system.
• Start the vehicle and allow it to reach operating temperature.