what does error code P0420 mean for my Tesla Model 3 Highland (2024-present)?

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety while working on electrical systems.
• Allow the vehicle to cool if the exhaust system was recently in use.

2. Inspect and Replace Oxygen Sensors

• Remove the oxygen sensors:
  1. Locate the upstream and downstream oxygen sensors.
  2. Use a socket wrench to carefully unscrew and remove the sensors.
• Install new oxygen sensors:
  1. Apply anti-seize compound to the threads of the new sensors.
  2. Screw in the new sensors and tighten them to the manufacturer's specifications (typically around 30 Nm).

3. Inspect and Replace the Catalytic Converter

• Remove the old catalytic converter:
  1. Disconnect any heat shields or brackets securing the catalytic converter.
  2. Unbolt the catalytic converter from the exhaust system using a socket set and ratchet.
• Install the new catalytic converter:
  1. Position the new catalytic converter in place and align it with the exhaust system.
  2. Bolt it securely, ensuring all gaskets are in good condition to prevent leaks.
  3. Reattach any heat shields or brackets.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle's battery.
• Use an OBD-II scanner to clear the P0420 error code from the system.