how to fix P0420 code on Tesla Model S Plaid/Refresh (2021-present)

• •Check engine light illuminated
• •Decreased fuel efficiency
• •Engine performance issues during acceleration
• •Unusual exhaust odors
• •Possible increase in emissions

1. 1Scan the vehicle's OBD-II system for error codes to confirm P0420 and check for any additional codes.
2. 2Inspect the exhaust system for leaks or damage, especially before and after the catalytic converter.
3. 3Check the exhaust gas temperature (EGT) sensors for proper function and calibration.
4. 4Inspect the catalytic converter visually for signs of physical damage or contamination.
5. 5Measure the voltage output from the oxygen sensors before and after the catalytic converter to determine if they are operating correctly.
6. 6Review the vehicle's maintenance history for any recent changes or repairs that could affect the exhaust system.

After completing the repair, verify that the issue has been resolved:

• ✓Test the affected component to ensure it functions correctly
• ✓Check for any error codes or warning lights
• ✓Monitor the vehicle for a few days to ensure the issue does not recur

To prevent this issue from occurring again:

• •Follow the manufacturer's recommended maintenance schedule
• •Address warning signs early before they develop into major issues
• •Use quality parts and fluids recommended for your vehicle
• •Keep detailed records of all repairs and maintenance

• •OBD-II scanner
• •Exhaust hangers removal tool
• •O2 sensor socket
• •Torque wrench
• •Basic hand tools (wrench set)

• •Oxygen sensors (if needed)
• •Catalytic converter (if needed)
• •Exhaust gaskets