how can I fix the P0420 code in my Tesla Model 3 Original (2017-2023)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery to prevent electrical shorts.
• Ensure the vehicle is parked on a level surface with the parking brake engaged.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Use a socket wrench to remove the sensors from the exhaust system.
  3. Inspect the sensor connectors for corrosion or damage.
  4. Install new oxygen sensors, ensuring to use anti-seize compound on the threads.
  5. Torque the sensors to the manufacturer's specifications (typically around 30 lb-ft).

3. Inspect and Replace Catalytic Converter

• Sub-steps:
  1. Remove any heat shields or brackets securing the catalytic converter.
  2. Detach the exhaust pipes connected to the catalytic converter using a socket set.
  3. Remove the old catalytic converter and inspect the mounting surfaces for damage.
  4. Install the new catalytic converter, ensuring proper alignment with the exhaust system.
  5. Reattach any heat shields or brackets and torque the bolts to the manufacturer's specifications.

4. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the vehicle's battery terminal securely.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
  3. Start the vehicle and allow it to reach operating temperature.