how to troubleshoot P0420 code in Tesla Model S Original (2012-2020)

Learn how to troubleshoot and fix P0420 exhaust system issues in Tesla Model S. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety during repairs.

2. Inspect and Replace O2 Sensors

• Tools Required: O2 sensor socket, torque wrench.
• Remove the O2 sensor(s) located before and after the catalytic converter.
  • Use the O2 sensor socket to unscrew the sensor.
  • Inspect the sensors for damage or contamination.
• If faulty, replace the O2 sensors with new, OEM parts.
• Torque the new O2 sensors to the manufacturer’s specifications (typically around 30 lb-ft).

3. Inspect and Clean Catalytic Converter

• Tools Required: High-temperature catalytic converter cleaner (if applicable).
• If the catalytic converter is clogged, use a high-temperature cleaner according to the product instructions.
• If the converter is severely damaged, it may need to be replaced.
• Remove the catalytic converter by unscrewing the bolts connecting it to the exhaust system.
• Install a new catalytic converter, ensuring proper alignment and secure it with bolts to the manufacturer’s specifications (torque values typically around 45 lb-ft).

4. Exhaust System Leak Repair

• Inspect all exhaust joints and connections for leaks.
• Use exhaust sealant or replace gaskets as necessary to ensure a tight seal.
• Reassemble all connections securely to prevent leaks.

5. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.
• Start the vehicle and allow it to reach operating temperature.