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

• •Check engine light illuminated
• •Decreased fuel efficiency
• •Loss of power during acceleration
• •Unusual exhaust odor
• •Increased emissions during testing

1. 1Scan for error codes using an OBD-II scanner to confirm the P0420 code.
2. 2Inspect the exhaust system for any visible leaks or damage.
3. 3Check the condition and connections of the O2 sensors upstream and downstream of the catalytic converter.
4. 4Verify that the catalytic converter is not clogged by performing a backpressure test.
5. 5Review the vehicle's service history for any recent repairs or modifications that could affect the catalytic system.
6. 6Inspect the engine for any conditions that could lead to excessive fuel entering the exhaust system, such as misfires or rich fuel conditions.

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
• •O2 sensor socket
• •Multimeter
• •Torque wrench
• •Jack and jack stands
• •Exhaust system cleaning solution
• •Wire brush
• •High-temperature sealant

• •O2 sensors (if faulty)
• •Catalytic converter (if damaged)
• •Exhaust system cleaning solution