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

Solution

1. Preparation

• Gather all necessary tools and parts.
• Disconnect the negative terminal of the battery to ensure safety.
• Allow the engine to cool down completely.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, wrench set, torque wrench, multimeter.
• Remove the pre-catalytic oxygen sensor using the O2 sensor socket.
• Inspect the connector and wiring for damage.
• If the sensor is faulty, install a new sensor and torque it to the manufacturer's specifications (typically around 30 Nm).
• Repeat the process for the post-catalytic oxygen sensor if necessary.

3. Inspect and Replace Catalytic Converter (if needed)

• Tools Required: Socket set, jack stands, exhaust hanger removal tool.
• Raise the vehicle and secure it with jack stands.
• Remove exhaust hangers to free the catalytic converter (use exhaust hanger removal tool).
• Unbolt the catalytic converter from the exhaust manifold and the mid-pipe.
• Inspect the catalytic converter for damage; if found defective, replace it with a new unit.
• Reinstall the new catalytic converter and torque bolts to the manufacturer's specifications.

4. Clear Codes and Test Drive

• Reconnect the battery terminal.
• Use the OBD-II scanner to clear the P0420 code.
• Start the engine and perform a test drive under various conditions to ensure the issue is resolved.