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

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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to prevent any electrical issues during repair.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Disconnect the wiring harness from each oxygen sensor.
  3. Use the O2 sensor socket to remove the sensors from the exhaust manifold and exhaust pipe.
  4. Install the new oxygen sensors, ensuring they are tightened to the manufacturer's specifications (typically around 30 ft-lbs).
  5. Reconnect the wiring harness to the new sensors.

3. Evaluate and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack stands, exhaust clamp tool.
• Sub-steps:
  1. Support the vehicle securely with jack stands and remove the underbody protection if applicable.
  2. Disconnect the exhaust pipes from the catalytic converter using the exhaust clamp tool.
  3. Remove any mounting bolts securing the catalytic converter to the vehicle.
  4. Install the new catalytic converter in reverse order of removal, ensuring all bolts are tightened to the specified torque (typically around 25 ft-lbs).
  5. Reconnect the exhaust system securely and replace any protective covers.

4. Clear Codes and Test

• Reconnect the vehicle's battery.
• Use the OBD-II scanner to clear the P0420 code.
• Start the vehicle and allow it to reach operating temperature.