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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to avoid electrical shorts.
• Raise the vehicle using jack stands for safe access to the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench, penetrating oil.
• Check the upstream and downstream oxygen sensors for any signs of damage.
• If the sensors are faulty:
  1. Spray penetrating oil on the sensor threads.
  2. Using the O2 sensor socket, carefully unscrew the old sensor.
  3. Install the new sensor, tightening it to the manufacturer’s specified torque (usually around 30 lb-ft).
  4. Repeat for the downstream sensor if necessary.

3. Inspect the Catalytic Converter

• Tools Required: Visual inspection tools, possibly a stethoscope for noise detection.
• Check the catalytic converter for any physical damage or excessive corrosion.
• If damaged, proceed to replace the catalytic converter:
  1. Remove the exhaust clamps or bolts connecting the catalytic converter to the exhaust system.
  2. Separate the catalytic converter from the exhaust pipe.
  3. Install the new catalytic converter, ensuring proper alignment.
  4. Reattach any clamps or bolts, tightening them to the specified torque.

4. Clear the Codes

• Reconnect the battery.
• Use an OBD-II scanner to clear the P0420 code from the system.