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

Solution

1. Preparation

• Gather required tools and parts.
• Disconnect the vehicle's battery to ensure safety while working on electrical components.
• Raise the vehicle using jack stands if access to the undercarriage is needed.

2. Inspect and Replace O2 Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench
• Remove the upstream O2 sensor:
  • Locate the upstream O2 sensor (usually before the catalytic converter).
  • Use the O2 sensor socket to unscrew and remove the sensor.
• Install the new O2 sensor:
  • Apply anti-seize compound to the threads of the new sensor.
  • Torque to the manufacturer’s specifications (typically around 30 ft-lbs).
• Repeat the same process for the downstream O2 sensor if necessary.

3. Inspect and Replace Catalytic Converter

• Tools Required: Socket set, torch (if needed for rusted bolts), exhaust sealant
• Remove the catalytic converter:
  • Locate the catalytic converter and inspect for any obvious damage.
  • Disconnect any exhaust hangers and bolts securing the converter.
  • Carefully remove it from the vehicle.
• Install the new catalytic converter:
  • Position the new converter and secure it with the original or new bolts.
  • Use exhaust sealant on joints as needed.
  • Reattach exhaust hangers and ensure everything is secured.

4. Reset the ECU

• Tools Required: OBD-II scanner
• Reconnect the vehicle's battery.
• Use the OBD-II scanner to clear the P0420 code from the ECU.
• Perform a short drive cycle to allow the ECU to recheck the system.