how to fix P0420 code in Tesla Model S Original (2012-2020)

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

Solution

1. Preparation

• Ensure the vehicle is parked on a flat surface and the parking brake is engaged.
• Disconnect the negative terminal of the battery to prevent electrical shorts.
• Gather necessary tools and replacement parts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the oxygen sensor from the exhaust system before the catalytic converter using the O2 sensor socket.
  • Sub-steps:
    1. Disconnect the electrical connector from the oxygen sensor.
    2. Use the O2 sensor socket to remove the sensor.
    3. Install the new sensor and torque it to the manufacturer’s specifications (usually around 30-40 ft-lbs).
    4. Reconnect the electrical connector.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust clamps
• If the catalytic converter is found to be damaged or inefficient, it must be replaced.
  • Sub-steps:
    1. Remove the exhaust bolts connecting the catalytic converter to the exhaust system.
    2. Remove the catalytic converter from its mounting points.
    3. Install the new catalytic converter, ensuring all gaskets are new and in good condition.
    4. Torque the exhaust bolts to the manufacturer's specifications (typically around 30-40 ft-lbs).
    5. Reconnect any exhaust clamps or hangers.

4. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal and ensure it is secure.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.

5. Final Test

• Start the vehicle and allow it to reach operating temperature.
• Perform a test drive to ensure the check engine light does not reappear and that the vehicle operates smoothly.