how to fix P0420 code on Tesla Outback 5th Generation (2015-2019)

Solution

1. Preparation

• Gather necessary tools, parts, and safety equipment.
• Disconnect the battery before starting work to avoid electrical issues.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors
   • Find the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors in the exhaust system.
2. Remove the Oxygen Sensors
   • Use an oxygen sensor socket to carefully unscrew and remove the sensors.
   • Inspect the sensor threads and connectors for damage.
3. Install New Oxygen Sensors
   • Apply anti-seize compound to the threads of the new sensors.
   • Install the new sensors and tighten to manufacturer specifications (typically around 30-40 lb-ft).

3. Inspect and Replace Catalytic Converter (if necessary)

1. Examine the Catalytic Converter
   • Check for any visible damage, rattling, or exhaust blockages.
2. Remove the Exhaust Components
   • Use a socket set to disconnect the exhaust pipes connected to the catalytic converter.
3. Install New Catalytic Converter
   • Position the new catalytic converter in place, ensuring proper alignment.
   • Tighten all connections to manufacturer specifications (generally 25-35 lb-ft).
4. Reconnect Exhaust System
   • Reattach any exhaust hangers and ensure all bolts are secured.

4. Final Checks

1. Reconnect Battery
   • Reattach the battery terminals ensuring a secure connection.
2. Clear Codes
   • Use the OBD-II scanner to clear the P0420 code from the ECU.
3. Test Drive
   • Conduct a test drive to ensure the issue has been resolved and the check engine light does not reappear.