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

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the battery to ensure safety.
• Raise the vehicle securely on jack stands.

Tools Required:

• OBD-II scanner
• Multimeter
• Socket set
• Torque wrench
• Jack stands

2. Inspect and Replace Oxygen Sensors

1. Locate the oxygen sensors: Identify the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors in the exhaust system.
2. Disconnect the sensors: Use the appropriate socket or wrench to remove the sensors, taking care not to damage the wiring harness.
3. Test the sensors: Use a multimeter to measure voltage and resistance according to the specifications in the service manual. Replace any faulty sensors.
4. Install new sensors: Apply anti-seize compound on the threads of the new oxygen sensors and torque them to the manufacturer's specifications.

3. Inspect and Replace Catalytic Converter

1. Remove the exhaust components: If the catalytic converter is damaged, remove it by unbolting it from the exhaust system.
2. Inspect for damage: Check for blockages, cracks, or overheating signs on the catalytic converter. If damaged, replace with a new unit.
3. Install the new catalytic converter: Position the new catalytic converter and bolt it securely, ensuring all connections are tight.
4. Torque to specifications: Use a torque wrench to tighten bolts to the manufacturer's specifications.

4. Clear Codes and Test

1. Reconnect the battery.
2. Clear the P0420 code using the OBD-II scanner.
3. Start the engine and let it reach operating temperature.
4. Monitor the oxygen sensor readings to ensure they are functioning correctly.