how to fix P0420 code on Toyota Camry XV50 (2012-2017)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to prevent electrical shorts.
• Allow the engine to cool before starting work.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench.
• Remove the upstream (pre-catalytic) oxygen sensor:
  1. Disconnect the electrical connector.
  2. Use the O2 sensor socket to unscrew the sensor from the exhaust manifold.
• Install the new upstream oxygen sensor:
  1. Apply anti-seize compound to the threads of the new sensor.
  2. Torque the sensor to the manufacturer’s specifications (typically around 30 lb-ft).
  3. Reconnect the electrical connector.
• Repeat the process for the downstream (post-catalytic) oxygen sensor if necessary.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, jack stands, exhaust pipe cutter (if necessary).
• Remove the catalytic converter:
  1. Support the exhaust system with jack stands.
  2. Loosen the bolts connecting the catalytic converter to the exhaust pipe using a socket set.
  3. If the converter is welded on, use an exhaust pipe cutter to remove it.
• Install the new catalytic converter:
  1. Position the new converter in place and secure it using new gaskets and bolts.
  2. Torque the bolts to the specified value (usually around 30 lb-ft).
  3. Ensure there are no exhaust leaks.

4. Reset the OBD-II System

• Reconnect the negative battery terminal.
• Use the scanner to clear the P0420 code from the vehicle's computer.