how to resolve P0420 code in Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0420 catalytic converter issue 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 to ensure safety during repairs.
• Allow the vehicle to cool if it has been running.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Remove the connectors from the oxygen sensors.
  3. Use the O2 sensor socket to unscrew the sensors from their mounting points.
  4. Install the new sensors by threading them into place and tightening to manufacturer specifications (usually around 30 lb-ft).
  5. Reconnect the electrical connectors securely.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust gasket, penetrating oil.
• Steps:
  1. Locate the catalytic converter in the exhaust system.
  2. Use penetrating oil on the bolts securing the catalytic converter to ease removal.
  3. Unscrew and remove the catalytic converter from the exhaust system.
  4. Inspect the old catalytic converter for signs of damage or blockage.
  5. Install the new catalytic converter, ensuring to replace the exhaust gasket.
  6. Tighten the bolts to manufacturer's torque specifications.

4. Clear Codes and Test

• Tools Required: OBD-II scanner.
• Steps:
  1. Reconnect the vehicle's battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the vehicle and allow it to reach operating temperature.
  4. Perform a test drive to ensure that the check engine light does not reappear.