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

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a level surface and the engine is cool.
• Disconnect the battery to prevent any electrical issues.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, torque wrench
• Remove the upstream (pre-catalytic) oxygen sensor:
  • Locate the sensor on the exhaust manifold or pipe.
  • Use an O2 sensor socket to unscrew it.
• Install the new upstream oxygen sensor:
  • Apply anti-seize compound on the threads of the new sensor.
  • Screw it in by hand and then tighten to the manufacturer's torque specifications (typically around 30-40 Nm).
• Repeat the process for the downstream (post-catalytic) oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter (if needed)

• Tools Required: Socket set, jack and jack stands, exhaust pipe cutter
• Raise the vehicle using a jack and secure it with jack stands.
• Remove the catalytic converter:
  • Disconnect any exhaust hangers and bolts securing the converter to the exhaust system.
  • Use an exhaust pipe cutter to remove the old catalytic converter if it is welded in place.
• Install the new catalytic converter:
  • Position the new unit and secure it using new gaskets and bolts.
  • Ensure all connections are tight and properly aligned.

4. Clear Codes and Test Drive

• Reconnect the battery.
• Use an OBD-II scanner to clear the P0420 code.
• Start the engine and allow it to reach operating temperature.
• Conduct a test drive to ensure the check engine light does not reappear.