what does the P0420 code mean for my Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0420 catalytic converter efficiency issue in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts.
• Disconnect the vehicle’s battery to ensure safety.
• Raise the vehicle using a jack and support it with jack stands if needed.

2. Inspect and Test Oxygen Sensors

• Remove the connectors from the pre- and post-catalytic converter oxygen sensors.
• Use a multimeter to check the voltage output of both sensors while the vehicle is running.
  • Pre-catalytic sensor should fluctuate between 0.1V and 0.9V.
  • Post-catalytic sensor should have a steadier output.
• Replace any faulty oxygen sensors.

3. Inspect and Replace Catalytic Converter

• If the catalytic converter shows signs of damage:
  • Remove the exhaust pipes connected to the catalytic converter using a socket set.
  • Unbolt the catalytic converter from its mount.
  • Install the new catalytic converter and secure it with bolts to the exhaust system.
  • Ensure all gaskets are replaced and connections are leak-free.

4. Reconnect Components

• Reconnect the oxygen sensors to their respective positions.
• Reconnect the vehicle's battery.

5. Clear Codes and Test Drive

• Use the OBD-II scanner to clear the P0420 code from the vehicle's memory.
• Start the vehicle and monitor the check engine light during a test drive to ensure the issue is resolved.