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 tools and parts.
• Disconnect the negative terminal from the battery to ensure safety.
• Ensure the vehicle is parked on a flat surface and securely supported.

2. Inspect and Replace Oxygen Sensors

• Step 1: Locate the upstream and downstream oxygen sensors.
• Step 2: Disconnect the electrical connectors from both sensors.
• Step 3: Remove the sensors using an oxygen sensor socket or wrench.
• Step 4: Install the new oxygen sensors in the reverse order of removal, ensuring proper torque (typically around 30 lb-ft).
• Step 5: Reconnect the electrical connectors securely.

3. Assess and Replace the Catalytic Converter (if necessary)

• Step 1: Remove the heat shield (if applicable) to access the catalytic converter.
• Step 2: Disconnect the exhaust pipes from both ends of the catalytic converter by removing the bolts or clamps.
• Step 3: Remove any mounting brackets holding the catalytic converter in place.
• Step 4: Install the new catalytic converter, ensuring proper alignment and secure fitting.
• Step 5: Reattach the exhaust pipes and tighten bolts to the manufacturer's specifications (generally around 25 lb-ft).

4. Reset the OBD-II System

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