how to fix P0420 code on my Tesla Outback 5th Generation (2015-2019)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical issues during repairs.
• Safety glasses and gloves are recommended.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, multimeter.
• Remove the upstream (pre-catalytic converter) oxygen sensor:
  1. Use the O2 sensor socket to unscrew the sensor from its location.
  2. Disconnect the electrical connector.
• Install the new oxygen sensor:
  1. Apply anti-seize compound to the threads of the new sensor.
  2. Screw the new sensor into place and reconnect the electrical connector.
• Repeat for the downstream (post-catalytic converter) oxygen sensor if necessary.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust hanger removal tool.
• Remove the catalytic converter:
  1. Loosen and remove the bolts securing the catalytic converter to the exhaust pipe and exhaust manifold.
  2. Use the exhaust hanger removal tool to detach any hangers holding the converter.
• Install the new catalytic converter:
  1. Position the new converter and secure it with bolts.
  2. Torque bolts to manufacturer specifications (usually around 25-30 lb-ft, but check specifications).
  3. Reattach any hangers.

4. Clear Error Codes

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code.
• Start the engine and check for any reoccurrence of the code.