how to fix 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 engine is cool.
• Disconnect the battery to avoid electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors on the exhaust system.
  2. Using a socket or wrench, carefully unbolt the oxygen sensors. Be cautious not to damage the wiring.
  3. Inspect the sensor connectors and wiring for damage; replace any damaged components.
  4. Install the new oxygen sensors by tightening them to the manufacturer’s specified torque (typically around 30 Nm).
  5. Reconnect the battery.

3. Inspect and Replace the Catalytic Converter

• Sub-steps:
  1. Remove any heat shields or protective covers to access the catalytic converter.
  2. Unbolt the catalytic converter from the exhaust system using a socket set.
  3. Inspect for cracks or excessive wear; replace if necessary.
  4. Install the new catalytic converter and tighten to the manufacturer's specified torque.
  5. Reinstall heat shields or covers if removed.

4. Clear Error Codes

• Sub-steps:
  1. Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.
  2. Ensure the vehicle is in a readiness state for emissions testing if required.