how to fix P0420 code on 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 battery to prevent electrical damage.
• Allow the vehicle to cool before working on the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet and extension, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors near the catalytic converter.
  2. Use the O2 sensor socket to remove the sensors from their respective locations.
  3. Inspect the sensors for damage or excessive carbon buildup; replace if necessary.
  4. Install new oxygen sensors and torque to manufacturer specifications.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, jack stands, exhaust pipe cutter (if necessary), new gaskets.
• Sub-steps:
  1. Remove any heat shields covering the catalytic converter.
  2. Disconnect the exhaust pipes from the catalytic converter.
  3. If the converter is damaged, cut it out using the exhaust pipe cutter.
  4. Install the new catalytic converter with new gaskets, ensuring all connections are tight and secure.
  5. Reinstall heat shields and any components removed during the process.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle's battery terminals.
• Use the OBD-II scanner to clear the P0420 code from the vehicle's system.