how to fix the P0420 code on my Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix the P0420 code related to the exhaust system in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery.
• Ensure the vehicle is on a level surface and secure it with wheel chocks.

2. Inspect and Replace O2 Sensors

• Tools Required: O2 sensor socket, wrench set, dielectric grease.
• Remove the upstream and downstream O2 sensors using the O2 sensor socket.
• Inspect each sensor for signs of wear or damage.
• If faulty, replace them with new sensors.
• Apply dielectric grease to the threads of the new sensors to prevent corrosion.
• Reinstall the sensors and reconnect the wiring harness.

3. Examine and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust pipe cutter or saw, exhaust sealant.
• Remove any heat shields or brackets obstructing access to the catalytic converter.
• Using the exhaust pipe cutter or saw, carefully cut the old catalytic converter from the exhaust system.
• Install the new catalytic converter, ensuring proper alignment.
• Torque the bolts to the manufacturer's specifications.
• Apply exhaust sealant to ensure no leaks.

4. Clear Codes and Test Drive

• Reconnect the battery and use the OBD-II scanner to clear the P0420 code.
• Start the vehicle and allow it to reach operating temperature.
• Conduct a test drive to ensure proper functioning and check for any new codes.