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

Solution

1. Preparation

• Gather tools and parts needed.
• Disconnect the negative terminal of the battery to ensure safety while working on the electrical components.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors: Identify both the upstream (pre-catalytic converter) and downstream (post-catalytic converter) oxygen sensors.
2. Remove the Sensors:
   • Use an oxygen sensor socket and ratchet to unscrew the sensors.
   • Disconnect the wiring harness from each sensor.
3. Install New Sensors:
   • Apply anti-seize compound on the threads of the new sensors.
   • Screw in the new oxygen sensors and connect the wiring harness.
   • Torque the sensors to the manufacturer's specified value (typically around 30 ft-lbs).

3. Inspect and Replace the Catalytic Converter

1. Inspect for Damage: Check the catalytic converter for any signs of physical damage or severe corrosion.
2. Remove Exhaust Components:
   • Loosen clamps and bolts securing the exhaust system before and after the catalytic converter.
   • Carefully remove the catalytic converter from the exhaust system.
3. Install New Catalytic Converter:
   • Position the new catalytic converter in place.
   • Secure it with the original clamps and bolts, ensuring all connections are tight.
   • Torque all fasteners to the manufacturer’s specifications.

4. Clear the Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the engine control unit.