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

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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the parking brake is engaged.
• Disconnect the 12V battery to ensure safety during repairs.

2. Inspect and Replace Oxygen Sensors (if necessary)

• Tools Required: O2 sensor socket, ratchet and extensions, torque wrench.
• Sub-steps:
  1. Locate the oxygen sensors; the upstream (pre-catalytic converter) sensor is typically near the engine, and the downstream (post-catalytic converter) sensor is after the catalytic converter.
  2. Disconnect the electrical connectors from both oxygen sensors.
  3. Using the O2 sensor socket, remove the sensors from the exhaust system.
  4. Install new oxygen sensors, tightening them to the manufacturer's specified torque (usually around 30 lb-ft).
  5. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust clamps (if needed).
• Sub-steps:
  1. Locate the catalytic converter; it is typically mounted on the exhaust system.
  2. Remove any heat shields or covers obstructing access to the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter by removing the bolts or clamps.
  4. Remove the catalytic converter from its mounting points.
  5. Install the new catalytic converter, ensuring proper alignment and fit.
  6. Reattach the exhaust pipes and tighten all connections to the manufacturer's specifications.

4. Reconnect Battery and Reset Codes

• Reconnect the 12V battery.
• Use the OBD-II scanner to clear the P0420 code and any error codes.
• Ensure all connectors are secure and the vehicle is ready for a test drive.