what does it mean if my Tesla Model 3 Original (2017-2023) has a P0420 code

Solution

1. Preparation

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

2. Inspect and Replace O2 Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream O2 sensors.
  2. Disconnect the electrical connectors for both sensors.
  3. Use the O2 sensor socket to remove the upstream sensor first, then the downstream sensor.
  4. Install new O2 sensors in the reverse order of removal, ensuring proper torque (typically around 30 lb-ft).
  5. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, jack and jack stands, exhaust pipe cutter (if necessary), gaskets.
• Sub-steps:
  1. Raise the vehicle safely using jack stands.
  2. Remove any heat shields or components obstructing access to the catalytic converter.
  3. Disconnect the exhaust pipes from the catalytic converter using the socket set.
  4. Inspect the catalytic converter for signs of damage or clogging; replace if necessary.
  5. Install the new catalytic converter, ensuring gaskets are in place and securely fastened.
  6. Reattach any components removed previously.