how to fix P0420 code on 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 on a level surface and engage the parking brake.
• Disconnect the negative battery terminal to prevent electrical shocks.

2. Inspect and Replace Oxygen Sensors

1. Locate the upstream and downstream oxygen sensors on the exhaust system.
2. Use an O2 sensor socket to remove the sensors.
3. Inspect the sensors for damage or excessive carbon buildup.
4. If defective, install new oxygen sensors, ensuring they are tightened to manufacturer specifications (usually around 30 Nm).
5. Reconnect the electrical connectors securely.

3. Inspect and Replace the Catalytic Converter (if needed)

1. Remove any heat shields or covers obstructing access to the catalytic converter.
2. Detach the exhaust pipes from the catalytic converter using a socket set (usually requires a torque of 40-50 Nm for reinstallation).
3. Inspect the catalytic converter for signs of physical damage or blockage.
4. If the catalytic converter is faulty, replace it with a new unit, ensuring the replacement meets OEM specifications.
5. Reassemble the exhaust system, tightening all bolts to the required torque specifications.

4. Reset the Engine Control Unit (ECU)

1. Reconnect the negative battery terminal.
2. Use the OBD-II scanner to clear the P0420 code from the ECU.
3. Start the vehicle and allow it to reach operating temperature.