how to fix P0420 code in my Tesla Model 3 Highland (2024-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety during repairs.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Unplug the electrical connectors from the sensors.
  3. Use the O2 sensor socket to remove the sensors from their mounting locations.
  4. Install new oxygen sensors, ensuring they are torqued to the manufacturer's specifications.
  5. Reconnect the electrical connectors securely.

3. Check and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack stands, exhaust gasket.
• Sub-steps:
  1. Elevate the vehicle securely on jack stands.
  2. Inspect the catalytic converter for any visible damage or signs of clogging.
  3. Remove the exhaust pipes connected to the catalytic converter using the socket set.
  4. Disconnect any brackets or mounts holding the catalytic converter in place.
  5. Remove the old catalytic converter and install a new one, ensuring proper alignment.
  6. Reattach the exhaust pipes and any brackets, tightening to specified torque values.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle's battery.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.