how to diagnose P0420 code in Tesla Model S Original (2012-2020)

Learn how to diagnose and fix P0420 catalytic converter efficiency issue in Tesla Model S (2012-2020). Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the 12V battery to ensure safety while working on electrical components.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, penetrating oil
• Sub-steps:
  1. Locate the pre-catalytic and post-catalytic oxygen sensors.
  2. Use penetrating oil to loosen the sensors if they are rusted or stuck.
  3. Disconnect the electrical connectors from both oxygen sensors.
  4. Remove the sensors using the O2 sensor socket and replace them with new sensors.
  5. Torque the new sensors to the manufacturer's specifications (usually around 30 lb-ft).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, exhaust hanger removal tool, gasket scraper
• Sub-steps:
  1. Remove any exhaust hangers securing the catalytic converter using the exhaust hanger removal tool.
  2. Disconnect any exhaust pipes connected to the catalytic converter.
  3. Remove the bolts securing the catalytic converter to the exhaust system.
  4. Inspect the old catalytic converter for damage or blockage.
  5. Install the new catalytic converter, ensuring the correct orientation and sealing using new gaskets.
  6. Torque bolts to specified values (typically around 25 lb-ft).

4. Reconnect Battery and Clear Codes

• Reconnect the 12V battery.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.