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

Learn how to diagnose and fix P0420 code in Tesla Model S (2012-2020). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to ensure safety.
• Allow the vehicle to cool if the engine was recently running.

2. Inspect and Repair Exhaust System

• Tools Required: Socket set, torque wrench, exhaust leak detector
• Inspect the exhaust system for any leaks or damage. If any leaks are found, repair or replace the affected sections.
• Ensure all exhaust clamps and bolts are tightened to the manufacturer's specifications.

3. Replace Oxygen Sensors (if faulty)

• Tools Required: Oxygen sensor socket, torque wrench
• Identify the upstream and downstream oxygen sensors.
• Use an oxygen sensor socket to unscrew the faulty sensor from the exhaust system.
• Apply anti-seize compound to the threads of the new oxygen sensor.
• Install the new sensor and tighten to the manufacturer’s torque specification (usually around 30 ft-lbs).

4. Replace Catalytic Converter (if necessary)

• Tools Required: Wrench set, gasket scraper, new gaskets
• Remove any bolts or clamps securing the catalytic converter to the exhaust system.
• Carefully remove the old catalytic converter and clean the mating surfaces.
• Install the new catalytic converter with new gaskets, ensuring a proper fit and seal.
• Tighten all bolts to the specified torque (typically between 30-40 ft-lbs, depending on the model).

5. Reset the Check Engine Light

• Tools Required: OBD-II scanner
• Use the OBD-II scanner to clear the P0420 code from the vehicle’s computer.
• Reconnect the battery if it was disconnected.