how to fix P0420 code on Toyota RAV4 Fifth Generation (2019-present)

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, basic hand tools (wrenches and sockets), jack stands, safety goggles.
• Ensure the vehicle is on a flat surface and securely raise it using jack stands.
• Disconnect the battery to prevent electrical shock.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors:

   • The upstream oxygen sensor is located before the catalytic converter, and the downstream sensor is after it.

2. Remove the Oxygen Sensors:

   • Use a wrench or socket to carefully unscrew the oxygen sensors from their respective ports.
   • Check for any damage or corrosion on the connectors.

3. Install New Oxygen Sensors:

   • Apply anti-seize compound on the threads of the new sensors.
   • Screw the new sensors into place and tighten to the manufacturer's torque specifications (usually around 30-40 lb-ft).
   • Reconnect the electrical connectors.

3. Inspect and Replace Catalytic Converter (if necessary)

1. Check for Physical Damage:

   • Inspect the catalytic converter for any dents, cracks, or signs of overheating.

2. Remove the Old Catalytic Converter:

   • Disconnect any bolts or clamps holding the catalytic converter in place.
   • Remove it from the exhaust system.

3. Install the New Catalytic Converter:

   • Position the new catalytic converter in place.
   • Secure it using the bolts or clamps, tightening them to the specified torque (usually around 25-30 lb-ft).

4. Clear Engine Codes and Test

1. Reconnect the Battery:

   • Ensure all connections are secure and then reconnect the battery terminals.

2. Clear the OBD-II Codes:

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

3. Test Drive the Vehicle:

   • Drive the vehicle under various conditions to ensure the check engine light does not reappear.