how to fix P0420 catalyst efficiency code in Tesla Model 3 Original (2017-2023)

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a level surface and set the parking brake.
• Disconnect the 12V battery to avoid any electrical issues while working.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet set, torque wrench
• Remove the oxygen sensor(s) using the O2 sensor socket.
  • Disconnect the electrical connector.
  • Unscrew the sensor and set it aside.
• Install new oxygen sensors (if faulty).
  • Apply anti-seize compound to the threads of the new sensors.
  • Torque to manufacturer specifications (typically around 30-40 ft-lbs).
  • Reconnect the electrical connectors.

3. Inspect and Replace the Catalytic Converter (if necessary)

• Tools Required: Socket set, jack and jack stands, exhaust sealant
• Raise the vehicle using a jack and secure it with jack stands.
• Disconnect the exhaust pipes from the catalytic converter.
  • Use a socket set to remove bolts or clamps as necessary.
• Remove the catalytic converter.
  • Inspect the mounting points and any gaskets for damage.
• Install the new catalytic converter.
  • Ensure that all gaskets are replaced and use exhaust sealant if necessary.
  • Reconnect the exhaust pipes to the new converter and tighten all fasteners to specified torque.