how to fix P0420 code on Renault Clio V (2019-Present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool before beginning work on the exhaust system.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench
• Remove the upstream oxygen sensor using the O2 sensor socket.
  • Sub-step: Disconnect the electrical connector and unscrew the sensor.
• Inspect the sensor for corrosion or damage.
• If the sensor is faulty, replace it with a new one, tightening it to the manufacturer's specified torque (usually around 30 Nm).
• Repeat the process for the downstream oxygen sensor if necessary.

3. Examine and Replace Catalytic Converter

• Tools Required: Socket set, exhaust pipe cutter (if needed), gasket scraper
• Inspect the catalytic converter for signs of damage or blockage.
• If replacement is necessary, use a socket set to remove the bolts securing the catalytic converter to the exhaust system.
• Cut the exhaust pipe if it is damaged or if the converter is welded in place.
• Install the new catalytic converter, ensuring alignment with existing exhaust components.
  • Sub-step: Use new gaskets and secure the bolts to the manufacturer’s torque specifications.

4. Clear Error Codes and Perform Test Drive

• Reconnect the battery and use the OBD-II scanner to clear the P0420 code from the system.
• Start the engine and let it reach operating temperature.
• Take the vehicle for a test drive to monitor for any reoccurrence of the check engine light.