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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure safety while working on the electrical systems.
• Raise the vehicle using jack stands for better access to the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream oxygen sensor using the O2 sensor socket.
• Inspect the sensor for damage; replace if necessary.
• Install the new sensor and torque it to the manufacturer’s specification (typically around 30 ft-lbs).
• Repeat the process for the downstream oxygen sensor if indicated during diagnostics.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torch wrench, exhaust gasket (if applicable)
• Unbolt the catalytic converter from the exhaust manifold and the exhaust pipe.
• Inspect the catalytic converter for any signs of physical damage or clogging.
• If damaged, replace it with a new catalytic converter, ensuring to use one that meets OEM specifications.
• Reinstall the catalytic converter, using new gaskets if necessary, and torque the bolts to manufacturer specifications.

4. Clear the Codes and Test Drive

• Reconnect the battery and use the OBD-II scanner to clear the P0420 code.
• Start the vehicle and let it reach operating temperature.
• Conduct a test drive to ensure the engine runs smoothly and the check engine light does not reappear.