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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, jack stands, safety goggles, gloves.
• Ensure the vehicle is parked on a level surface and the engine is cool before beginning work.
• Disconnect the vehicle's 12V battery to prevent any electrical issues during the repair.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Unplug the electrical connectors from both sensors.
  3. Using a socket wrench, carefully remove the sensors from their mounting locations.
  4. Install new oxygen sensors, ensuring they are torqued to manufacturer specifications (typically around 30 ft-lbs).
  5. Reconnect the electrical connectors to the sensors.

3. Inspect and Clean Catalytic Converter

• Sub-steps:
  1. Inspect the catalytic converter for any physical damage, dents, or blockages.
  2. If the converter is clogged, use a catalytic converter cleaner fluid according to the manufacturer's instructions.
  3. Alternatively, if damaged, remove the catalytic converter using a socket set and replace it with a new one.
  4. Ensure all gaskets are replaced and connections are sealed to prevent exhaust leaks.

4. Clear Codes and Test Drive

• Sub-steps:
  1. Reconnect the vehicle's 12V battery.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's memory.
  3. Start the engine and allow it to reach operating temperature.
  4. Perform a test drive for at least 20 minutes to ensure the vehicle operates normally and monitor for the return of the check engine light.