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

Solution

1. Preparation

• Gather tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative terminal of the battery to prevent electrical issues.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet and extension, torque wrench.
• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors on the exhaust system.
  2. Remove the wiring harness from the sensors.
  3. Use the O2 sensor socket to unscrew the sensors from their locations.
  4. Install the new sensors by hand to avoid cross-threading, then tighten to the manufacturer's specified torque (typically around 30 lb-ft).
  5. Reconnect the wiring harness.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, torque wrench, exhaust pipe cutter, gasket scraper.
• Sub-steps:
  1. Locate the catalytic converter in the exhaust system.
  2. Use the socket set to unbolt the catalytic converter from the exhaust pipes.
  3. Carefully remove the old catalytic converter and clean the mating surfaces with a gasket scraper.
  4. Install the new catalytic converter, ensuring proper alignment and sealing.
  5. Torque the bolts to the manufacturer's specifications (typically around 30 lb-ft).

4. Reconnect Battery and Clear Codes

• Reconnect the negative terminal of the battery.
• Use the OBD-II scanner to clear the P0420 code from the system.