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

Solution

1. Preparation

• Gather tools and parts needed for the repair.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

1. Remove the upstream O2 sensor:
   • Use an O2 sensor socket and carefully unscrew the sensor.
   • Disconnect the wiring harness.
2. Install the new upstream O2 sensor:
   • Apply anti-seize compound on the threads of the new sensor.
   • Install and torque to manufacturer specifications (usually around 30 ft-lbs).
3. Repeat for the downstream O2 sensor if it's faulty.

3. Inspect and Replace Catalytic Converter

1. Remove the exhaust components:
   • Use a socket set to remove bolts holding the exhaust system.
   • Carefully detach the exhaust pipe from the catalytic converter.
2. Remove the catalytic converter:
   • Unscrew the bolts connecting it to the exhaust manifold.
   • Remove any brackets or hangers securing the converter.
3. Install the new catalytic converter:
   • Position and secure the new converter, ensuring proper alignment.
   • Torque the bolts to manufacturer specifications (typically around 25-35 ft-lbs).
4. Reattach the exhaust components:
   • Reinstall the exhaust pipe and any other components removed.

4. Reset the Engine Control Module

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