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

Solution

1. Preparation

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

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, multimeter.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors in the exhaust system.
  2. Disconnect the electrical connectors from each sensor.
  3. Use the O2 sensor socket to remove the old sensors from their respective locations.
  4. Install new oxygen sensors, ensuring to apply anti-seize compound on the threads if required.
  5. Reconnect the electrical connectors securely.

3. Inspect and Clean or Replace Catalytic Converter

• Tools Required: Socket set, exhaust pipe cutter, wrench set, safety goggles.
• Sub-steps:
  1. Inspect the catalytic converter for any physical damage or signs of clogging.
  2. If cleaning is necessary, use a high-temperature cleaner designed for catalytic converters.
  3. If replacement is required, cut the exhaust pipes using the exhaust pipe cutter to remove the damaged catalytic converter.
  4. Install the new catalytic converter, ensuring to use proper gaskets and secure it with bolts to the existing exhaust system.
  5. Torque the bolts to the manufacturer’s specifications.

4. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the system.