how to fix P0420 code on Tesla Model Y Current (2020-present)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the negative battery terminal to ensure safety while working on the vehicle.

2. Inspect and Clean Oxygen Sensors

• Tools Required: O2 sensor socket, cleaning brush, safety gloves
• Remove the downstream oxygen sensor using the O2 sensor socket.
• Inspect the sensor for contamination; if dirty, clean it using a brush and appropriate cleaner.
• Reinstall the sensor securely and reconnect any wiring that was disconnected.

3. Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, jack stands, torque wrench, exhaust gasket
• Raise the vehicle using jack stands to access the undercarriage.
• Remove any heat shields or brackets securing the catalytic converter.
• Unbolt the catalytic converter from the exhaust pipes, taking care to note the orientation and connections.
• Install the new catalytic converter in the same position, using a new gasket as necessary.
• Torque the bolts to the manufacturer's specifications (refer to the service manual for exact values).
• Reinstall any heat shields or brackets that were previously removed.

4. Reset the Engine Control Module (ECM)

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the ECM.
• Perform a short drive cycle to allow the vehicle to recalibrate and monitor for any reoccurrence of the code.