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

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to prevent electrical shorts.
• Ensure the vehicle is parked on a level surface and secured with wheel chocks.

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 on the exhaust pipe before the catalytic converter.
  2. Use an O2 sensor socket to unscrew the sensor.
• Install the new oxygen sensor:
  1. Apply anti-seize compound to the threads of the new sensor.
  2. Hand-tighten the sensor and then torque it to the manufacturer's specification (typically around 30 ft-lbs).

3. Inspect and Replace Catalytic Converter (if necessary)

• Tools Required: Socket set, exhaust hanger removal tool, jack stands.
• Remove the catalytic converter:
  1. Support the exhaust system with jack stands.
  2. Remove the bolts connecting the catalytic converter to the exhaust manifold and the downstream exhaust pipe.
  3. Cut any exhaust hangers if necessary.
• Install the new catalytic converter:
  1. Position the new converter and reconnect it to the exhaust manifold and downstream pipe.
  2. Torque the bolts to the specified value (usually around 30-35 ft-lbs).

4. Reconnect Battery and Clear Codes

• Reconnect the battery.
• Use the OBD-II scanner to clear the P0420 code and any other related codes.