how to fix P0420 code on my Tesla Model S Plaid/Refresh (2021-present)

Learn how to diagnose and fix P0420 exhaust system issue in Tesla Model S Plaid. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's 12V battery to ensure safety while working on the electrical system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench
• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Disconnect the electrical connectors from both oxygen sensors.
  3. Use the O2 sensor socket to remove the sensors from their respective locations.
  4. Install new oxygen sensors by threading them into place and tightening them to the manufacturer's specifications (typically around 30 ft-lbs).
  5. Reconnect the electrical connectors securely.

3. Inspect or Replace Catalytic Converter

• Tools Required: Socket set, exhaust jack, cutting tool (if necessary), gasket material
• Sub-steps:
  1. Raise the vehicle using a jack and secure it with jack stands.
  2. Inspect the catalytic converter for physical damage or clogging.
  3. If replacement is needed, unbolt the catalytic converter from the exhaust system carefully.
  4. Remove the old gasket material from the mating surfaces.
  5. Install the new catalytic converter using a new gasket, ensuring a proper seal.
  6. Torque the bolts to the manufacturer's specifications.

4. Clear Codes and Test

• Tools Required: OBD-II scanner
• Sub-steps:
  1. Use the OBD-II scanner to clear the P0420 code from the vehicle's memory.
  2. Start the vehicle and allow it to reach operating temperature.
  3. Take the vehicle for a test drive to monitor for reoccurrence of the code.