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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is on a level surface and the parking brake is set.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Sub-steps:
  1. Disconnect the negative terminal of the battery.
  2. Locate the upstream and downstream oxygen sensors.
  3. Use the O2 sensor socket to remove the upstream sensor first, followed by the downstream sensor if needed.
  4. Install new oxygen sensors, tightening them to the manufacturer's specified torque (usually around 30-45 Nm).
  5. Reconnect the battery terminal.

3. Examine and Replace the Catalytic Converter (if necessary)

• Tools Required: Socket set, jack stands, exhaust gasket
• Sub-steps:
  1. Safely lift the vehicle and support it with jack stands.
  2. Remove any heat shields or protective covers over the catalytic converter.
  3. Detach the exhaust pipe from the catalytic converter using the socket set.
  4. Remove the old catalytic converter, ensuring to keep any gaskets for reuse or replace with new ones if damaged.
  5. Install the new catalytic converter, ensuring proper alignment and sealing.
  6. Reattach the exhaust pipe and any heat shields previously removed.

4. Clear Error Codes

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Reconnect the battery if disconnected.
  2. Use the OBD-II scanner to clear the P0420 code from the vehicle's system.