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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the battery to avoid electrical issues.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench
• Remove the connectors from the upstream and downstream oxygen sensors.
• Use an O2 sensor socket to unscrew the sensors from the exhaust manifold (upstream) and catalytic converter (downstream).
• Install new oxygen sensors and tighten to the manufacturer’s specifications (typically around 30 lb-ft or 40 Nm).
• Reconnect the oxygen sensor connectors.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, torque wrench, exhaust hanger removal tool
• Disconnect the exhaust system from the catalytic converter by unbolting the flange connections.
• Remove any exhaust hangers holding the catalytic converter in place.
• Carefully remove the old catalytic converter from the exhaust system.
• Install the new catalytic converter, ensuring proper alignment and fit.
• Reattach the exhaust system and tighten all bolts to the manufacturer’s torque specifications.

4. Clear Codes and Test

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