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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Remove the upstream oxygen sensor using an O2 sensor socket.
• Inspect the sensor for damage and replace it if necessary.
• Install the new oxygen sensor, torque it to manufacturer specifications (typically 30 lb-ft).
• Repeat the process for the downstream oxygen sensor.

3. Replace the Catalytic Converter

• Tools Required: Socket set, exhaust pipe cutter, gasket scraper, new exhaust gaskets.
• Raise the vehicle using a jack and secure it with jack stands.
• Disconnect the exhaust pipes from the catalytic converter using a socket set.
• Cut the old catalytic converter out if necessary, using an exhaust pipe cutter.
• Clean the exhaust flanges with a gasket scraper to ensure a good seal.
• Install the new catalytic converter with new gaskets, securing it tightly with the appropriate bolts.

4. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 trouble code.
• Start the engine and allow it to reach operating temperature.