how to fix P0420 code on Tesla Model 3 Original (2017-2023)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is on a level surface and the parking brake is engaged.
• Disconnect the vehicle battery to prevent electrical issues.

2. Inspect and Replace Oxygen Sensors (if faulty)

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the upstream and downstream oxygen sensors:
  • Locate the sensors along the exhaust system.
  • Use the O2 sensor socket to unscrew the sensors.
• Install new oxygen sensors:
  • Apply anti-seize compound to the threads of the new sensors.
  • Torque each sensor to the manufacturer's specifications (generally around 30 lb-ft).

3. Inspect and Replace Catalytic Converter (if damaged)

• Tools Required: Socket set, torque wrench, exhaust pipe cutter (if necessary)
• Remove the catalytic converter:
  • Disconnect the exhaust pipes leading to and away from the catalytic converter.
  • Use the socket set to remove any bolts or clamps securing the converter.
• Install the new catalytic converter:
  • Position the new converter and secure it using new gaskets and bolts.
  • Torque the bolts to the manufacturer's specifications (typically around 40 lb-ft).

4. Reconnect Battery and Clear Codes

• Reconnect the battery and ensure all connections are tight.
• Use the OBD-II scanner to clear the P0420 code.