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

Learn how to diagnose and fix P0420 code in Tesla Model S. Step-by-step guide with symptoms, diagnostic steps, tools, and repair instructions.

Solution

1. Preparation

• Ensure the vehicle is parked on a flat surface and the ignition is off.
• Disconnect the negative terminal of the 12V battery to prevent electrical shorts.
• Gather all necessary tools and parts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, penetrating oil, safety gloves
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Apply penetrating oil to the sensor threads if they are rusted.
  3. Carefully unscrew the upstream O2 sensor using the O2 sensor socket.
  4. Install the new upstream O2 sensor and torque to manufacturer specifications (usually around 30 ft-lbs).
  5. Repeat the process for the downstream O2 sensor.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, gasket scraper, exhaust sealant, safety gloves
• Sub-steps:
  1. Raise the vehicle securely on jack stands to access the undercarriage.
  2. Remove any shielding or brackets obstructing access to the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter by unbolting the flange connections.
  4. Remove the catalytic converter from its mounting points.
  5. Install the new catalytic converter, ensuring proper alignment and fitment.
  6. Use a new gasket and apply exhaust sealant to prevent leaks. Torque all bolts to the manufacturer's specifications.

4. Reconnect Battery and Clear Codes

• Reconnect the negative terminal of the 12V battery.
• Use the OBD-II scanner to clear the P0420 code from the system.
• Start the engine and allow it to reach operating temperature.