how to resolve recurring P0420 code in Tesla Model 3 Original (2017-2023)?

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the ignition is off.
• Disconnect the battery to prevent any electrical shorts.

2. Oxygen Sensor Inspection

• Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
• Use a socket wrench to remove both sensors if they are found to be faulty.
• Inspect the sensors for contamination or damage. If necessary, replace them with OEM parts.

3. Exhaust System Repair

• Inspect the entire exhaust system for leaks, focusing on joints and welds.
• If any leaks are found, repair or replace sections of the exhaust system as needed.
• Ensure all gaskets are in good condition and replace them if they show signs of wear.

4. Catalytic Converter Testing

• Using an infrared thermometer, measure the temperature at the inlet and outlet of the catalytic converter.
• The inlet temperature should be lower than the outlet temperature. A significant temperature drop indicates proper functioning.
• If the converter is faulty, replace it with a new OEM catalytic converter, following the manufacturer’s specifications for installation.

5. Software Update

• Check for any available software updates for the vehicle by connecting to Tesla’s service center or using the Tesla app.
• Follow instructions to install any updates that may resolve the efficiency monitoring issue.