how to fix the P0420 code on my Tesla Model 3 Original (2017-2023)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors in the exhaust system.
  2. Disconnect the electrical connectors from the sensors.
  3. Use a wrench to remove the sensors from their mounting locations.
  4. Install new oxygen sensors (ensure they are compatible with Tesla Model 3).
  5. Torque the new sensors to the manufacturer’s specifications (usually around 30 lb-ft).
  6. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Sub-steps:
  1. Remove any heat shields or brackets securing the catalytic converter.
  2. Disconnect the exhaust pipes from the catalytic converter by loosening the clamps.
  3. Carefully remove the catalytic converter from the exhaust system.
  4. Install the new catalytic converter, ensuring proper alignment.
  5. Reattach the exhaust pipes and tighten clamps to the manufacturer’s specifications.
  6. Reinstall heat shields or brackets as necessary.

4. Clear Codes and Test

• Sub-steps:
  1. Reconnect the battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the engine and let it reach operating temperature.
  4. Conduct a test drive to ensure the issue is resolved.