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

Solution

1. Preparation

• Gather tools and parts required for the repair.
• Disconnect the battery to prevent electrical shorts while working.
• Allow the vehicle to cool down if the engine has been running.

2. Inspect and Replace O2 Sensors

1. Locate the upstream and downstream O2 sensors on the exhaust system.
2. Unplug the electrical connectors from both sensors.
3. Use an O2 sensor socket to remove the sensors from the exhaust system.
4. Install new O2 sensors using anti-seize compound on the threads and tighten to manufacturer's specifications (typically 30 Nm / 22 lb-ft).
5. Reconnect the electrical connectors securely.

3. Inspect and Replace Catalytic Converter (if necessary)

1. If the catalytic converter appears damaged, remove it by unbolting it from the exhaust manifold and the exhaust pipe.
2. Install a new catalytic converter, ensuring proper alignment with gaskets.
3. Torque the bolts to the specifications (usually around 41 Nm / 30 lb-ft, but check specific vehicle guidelines).
4. Reconnect any sensors or components removed during the process.

4. Reconnect Battery and Clear Codes

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