how to fix P0420 code on Toyota Camry XV70 (2018-2024)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to ensure safety during repairs.

2. Inspect and Replace Oxygen Sensors

• Required Tools: O2 sensor socket, wrench set, torque wrench.
• Remove the upstream oxygen sensor:
  • Locate the sensor before the catalytic converter.
  • Use the O2 sensor socket to unscrew it from the exhaust manifold.
• Install the new upstream oxygen sensor:
  • Apply anti-seize compound to the threads.
  • Torque to manufacturer specifications (usually around 30 lb-ft).
• Repeat the process for the downstream oxygen sensor (post-catalytic converter).

3. Inspect and Replace the Catalytic Converter

• Required Tools: Socket set, jack and jack stands, exhaust pipe cutter (if necessary).
• Remove the exhaust system components as needed to access the catalytic converter:
  • Support the exhaust system with a jack.
  • Unbolt the catalytic converter from the exhaust manifold and exhaust pipe.
• Install the new catalytic converter:
  • Ensure proper alignment with the exhaust system.
  • Torque the bolts to manufacturer specifications (typically 30-35 lb-ft).
• Reconnect any removed exhaust components.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle battery.
• Use the OBD-II scanner to clear the P0420 code.
• Start the engine and allow it to reach operating temperature.