how to troubleshoot P0420 code on Ford F-150 13th Generation (2015-2020)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the exhaust system to cool down before inspection.

2. Inspect and Replace Oxygen Sensors

1. Locate the pre-catalytic and post-catalytic oxygen sensors.
2. Using an oxygen sensor socket, carefully remove the sensors from their respective locations.
3. Inspect the sensors for signs of damage or contamination.
4. Install new oxygen sensors, ensuring they are torqued to manufacturer specifications (typically around 30 lb-ft).
5. Reconnect the electrical connectors securely.

3. Examine and Replace the Catalytic Converter (if necessary)

1. Inspect the catalytic converter for any visible damage or signs of clogging.
2. If replacement is necessary, unbolt the catalytic converter from the exhaust system using a socket set.
3. Install the new catalytic converter, ensuring proper alignment and a tight fit.
4. Torque the bolts to the manufacturer’s specifications (usually around 30-35 lb-ft).
5. Reconnect any sensors or heat shields removed during the process.

4. Clear Codes and Test Drive

1. Reconnect the battery and use the OBD-II scanner to clear the P0420 code.
2. Start the engine and allow it to reach operating temperature.
3. Take the vehicle for a test drive to monitor for any reoccurrence of the P0420 code.