how to fix P0420 code on Honda CR-V Sixth Generation (2023-present)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle's battery to ensure safety.
• Allow the exhaust system to cool before starting work.

2. Inspect and Replace Oxygen Sensors

1. Locate the Oxygen Sensors: Identify the upstream (pre-catalytic) and downstream (post-catalytic) oxygen sensors.
2. Remove the Old Sensors:
   • Use an oxygen sensor socket to unscrew the upstream sensor first.
   • Disconnect the electrical connector.
3. Install New Sensors:
   • Apply anti-seize compound to the threads of the new oxygen sensors.
   • Install the upstream sensor and torque it to the manufacturer’s specified value (usually around 30-40 lb-ft).
   • Connect the electrical connector.
   • Repeat for the downstream sensor.

3. Inspect and Replace Catalytic Converter

1. Remove Exhaust Components: If the catalytic converter is suspected to be faulty, remove the pipe bolts or clamps that secure it.
2. Inspect the Catalytic Converter:
   • Check for physical damage or signs of clogging (e.g., rattling noise when shaken).
3. Install New Catalytic Converter:
   • Position the new catalytic converter in place.
   • Secure it with the original bolts or clamps, torquing to manufacturer specifications (typically around 30-50 lb-ft).
   • Ensure all gaskets are properly seated to avoid leaks.

4. Reconnect Battery and Clear Codes

• Reconnect the vehicle’s battery and use the OBD-II scanner to clear the P0420 code from the ECM.