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

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, torque wrench, jack and jack stands, safety glasses, gloves.
• Safety Warnings: Disconnect the 12V battery before working on electrical systems.

2. Inspect and Clean Oxygen Sensors

• Sub-steps:
  1. Locate the upstream and downstream oxygen sensors.
  2. Disconnect the wiring harness from each sensor.
  3. Remove the sensors using a socket wrench.
  4. Inspect for any carbon build-up; clean with a suitable sensor cleaner.
  5. Reinstall the cleaned sensors and reconnect the wiring.

3. Examine and Test Catalytic Converter

• Sub-steps:
  1. Inspect the catalytic converter for physical damage or signs of clogging.
  2. Use a temperature gauge to measure the inlet and outlet temperatures.
  3. If the outlet temperature is not significantly higher than the inlet, the catalytic converter may be faulty.
  4. If damaged or inefficient, replace the catalytic converter.

4. Replace with Quality Components

• Sub-steps:
  1. If necessary, procure a new catalytic converter and ensure it meets OEM specifications.
  2. Remove the old catalytic converter by unbolting it from the exhaust system.
  3. Install the new catalytic converter, ensuring proper alignment.
  4. Torque the bolts to the manufacturer’s specifications.

5. Reconnect Battery and Clear Codes

• Sub-steps:
  1. Reconnect the 12V battery.
  2. Use the OBD-II scanner to clear the P0420 code.
  3. Start the vehicle and allow it to reach operating temperature.