how to fix P0420 code on Toyota Camry Eighth Generation (2018-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench
• Sub-steps:
  1. Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
  2. Unplug the electrical connectors from both sensors.
  3. Use the O2 sensor socket to remove the sensors from the exhaust manifold and converter.
  4. Install new oxygen sensors, ensuring proper torque (typically 30-40 lb-ft).
  5. Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, exhaust pipe cutter, gasket scraper, high-temperature gasket maker
• Sub-steps:
  1. Inspect the catalytic converter for physical damage or blockage.
  2. If replacement is necessary, disconnect any exhaust hangers and remove the exhaust pipes connected to the catalytic converter.
  3. Remove the catalytic converter using a socket set.
  4. Install the new catalytic converter, ensuring that all gaskets are in good condition and properly sealed.
  5. Reconnect the exhaust pipes and hangers.

4. Reconnect Battery and Clear Codes

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