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 flat surface and the engine is cool.
• Disconnect the negative battery terminal to prevent electrical shorts.

2. Inspect and Replace Oxygen Sensors

• Tools Required: O2 sensor socket, ratchet, torque wrench.
• Remove the upstream (pre-catalytic) oxygen sensor:
  1. Locate the sensor in the exhaust manifold or exhaust pipe.
  2. Use the O2 sensor socket to unscrew the sensor.
  3. Install the new sensor and torque it to the manufacturer's specifications (typically around 30 Nm).
• Repeat the process for the downstream (post-catalytic) oxygen sensor.

3. Inspect and Replace the Catalytic Converter

• Tools Required: Socket set, jack and jack stands, exhaust clamps, gasket scraper, new gaskets.
• Raise the vehicle safely using jack stands:
  1. Locate the catalytic converter in the exhaust system.
  2. Remove the exhaust clamps or bolts securing the catalytic converter to the exhaust pipes.
  3. Carefully detach the catalytic converter and inspect it for damage or clogging.
  4. If replacement is necessary, install the new catalytic converter, ensuring to use new gaskets and torque the bolts to the manufacturer’s specifications.

4. Reconnect Battery and Clear Codes

• Reconnect the negative battery terminal.
• Use the OBD-II scanner to clear the P0420 code from the vehicle's computer.