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

Solution

1. Preparation

• Gather tools and parts required.
• Park the vehicle on a flat surface and engage the parking brake.
• Disconnect the battery to prevent electrical shorts.

2. Inspect and Test Oxygen Sensors

• Tools Required: OBD-II scanner, multimeter
• Remove the upstream (pre-catalytic converter) oxygen sensor:
  1. Locate the sensor on the exhaust manifold.
  2. Use a socket to unscrew and remove the sensor.
• Test the sensor:
  1. Connect the multimeter to the sensor's terminals.
  2. Check for voltage output while the engine is running.
  3. If faulty, replace with a new oxygen sensor.

3. Inspect Catalytic Converter

• Tools Required: Temperature gauge, socket set
• Check the temperature:
  1. Start the engine and let it reach operating temperature.
  2. Measure the temperature at the inlet and outlet of the catalytic converter.
  3. A significant difference (more than 100°F) indicates proper function; if not, consider replacing the catalytic converter.

4. Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, exhaust sealant, gaskets
• Remove the catalytic converter:
  1. Loosen and remove the bolts connecting the converter to the exhaust pipe.
  2. Disconnect any hangers or brackets holding the converter in place.
  3. Carefully remove the old converter.
• Install the new catalytic converter:
  1. Position the new converter in place and secure it with bolts.
  2. Ensure all gaskets are properly seated and use exhaust sealant if necessary.
  3. Reattach any hangers or brackets.

5. Reconnect Battery and Clear Codes

• Reconnect the battery terminals.
• Use the OBD-II scanner to clear the P0420 code from the system.
• Start the engine and allow it to run for a few minutes.