how to fix P0420 code on my Toyota RAV4 Fourth Generation (2013-2018)

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery terminals to prevent electrical shorts.
• Allow the exhaust system to cool before working on it.

2. Inspect and Replace Oxygen Sensors

1. Remove Old Sensors:

   • Locate the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
   • Use an oxygen sensor socket to carefully unscrew and remove both sensors.

2. Install New Sensors:

   • Apply anti-seize compound to the threads of the new oxygen sensors.
   • Install the upstream sensor first, followed by the downstream sensor, ensuring they are tightened to the manufacturer's torque specifications (typically around 30 ft-lbs).

3. Inspect Catalytic Converter

1. Visual Inspection:

   • Check for any signs of damage or overheating on the catalytic converter.
   • Look for rattling noises indicating internal failure.

2. Replace Catalytic Converter (if necessary):

   • If damaged, disconnect the exhaust pipes from the catalytic converter using a socket set.
   • Remove any mounting brackets or hangers.
   • Install the new catalytic converter and make sure to align it with the exhaust system properly.
   • Tighten all bolts to the manufacturer's specifications.

4. System Reset

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

5. Test Drive

• Start the vehicle and allow it to reach operating temperature.
• Monitor the vehicle for any warning lights or symptoms during a test drive.